o UJ 3 L I B R.A FLY OF THE UNIVER.5 ITY Of 1LLI NOIS «=>©<»>. 2» NATURAL HISTORY /AM. f* 4 *6i5-'0 PHYCOLOGIA BRITANNICA: A HISTORY OF BRITISH SEA-WEEDS, CONTAINING COLOURED FIGURES, GENERIC AND SPECIFIC CHARACTERS SYNONYMES, AND DESCRIPTIONS ALL THE SPECIES OF ALGiE INHABITING THE SHORES OF THE BRITISH ISLANDS. WILLIAM HENRY HARVEY, M.D., M.R.I.A. Keeper of the Herbarium of the University of Dublin. IN THREE VOLUMES. VOL. I. LONDON: REEVE, BROTHERS, KING WILLIAM STREET, STRAND. 184G. REEVE, BROTHERS, PRINTERS AND LITHOGRAPHERS OF SCIENTIFIC WORKS, KING WILLIAM STREET, STRAND. VU(?P SIR WILLIAM JACKSON HOOKER, K.H., D.C.L., F.R.S., V.P.L.S., etc., etc., Erector of tfjt ftooal Botanic ©aronu* of 5&rto, THIS WOEK IS INSCRIBED AS A SHALL TRIBUTE OF THE WARM AFFECTION, ADMIRATION, AND GRATITUDE r7 fi OF HIS ATTACHED FRIEND, THE AUTHOR. Digitized by the Internet Archive in 2010 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/phycologiabritan01har ADVERTISEMENT. IN the Introduction to my " Manual of the British Algae," pub- lished on the eve of my last voyage to the Cape of Good Hope, I stated the strong wish that I felt of accompanying the descrip- tions in that little work by plates, illustrative at least of the genera, and apologised for their omission by the briefness of my stay in Europe. Since my final return home I have been fre- quently applied to, by persons interested in marine botany, to fulfil in some way the promise then partly held out, either by publishing a new, enlarged, and illustrated edition of the " Ma- nual," or a new work on the same subject, and on an extended plan. After some consideration I have preferred the latter course, and undertaken the present Work, in which it is intended first to give coloured figures, accompanied by detailed descriptions, of every British species of Marine Algae or Sea-weed ; and, on the completion of this portion of the work, to add to the last volume a general Introduction to Marine Botany, and a systematic synopsis of the British Marine Flora. The recent publication of Mr. Hassall's ' History of the British Freshwater Algae,' in which he has given figures of all the species known to him, affords me an opportunity of limiting my atten- tion to the marine algae, which are so much more attractive to the generality of students and collectors, and thus enables me to reduce the number of plates and the consequent expense of the work very considerably. — I also propose to omit the Desmidie^e ADVERTISEMENT. andDiATOiiACE^:, tribes of organised beings which can hardly be regarded as genuine Algae, but rather as forming a Class so nearly balanced between the animal and vegetable kingdoms, that those who have most attentively studied them are divided in sentiment respecting the kingdom to which they belong. I the more readily omit them because Mr. Ralfs— the Lyonnet of this department of Natural History — is preparing a separate work, to lie accom- panied by coloured plates, on these Families. Every admirer of patient industry, acute observation, and extensive research into these hidden tilings of nature, — one of her worlds of whose existence, though distributed in all waters and all lands, we are unconscious till the microscope reveals them to us, — must rejoice that a work requiring so much acmnen and patience has fallen into such able hands. As some set-off against the above omissions, the present work will include the British species of CoraUina, Hdimeda and N/dJi- pora, which recent discoveries and observations have fairly proved to belong not merely to the vegetable kingdom, but to be closely connected by affinity with many of the Algae ; in short, to be Algas in disguise, some of them related by their fructification to Rhodomelea, others to Batrackospermum, and others again to Codium and Bryojms. With regard to the method of publication, two plans suggest themselves, each of which has its advantages. The first is, having taken a view of the whole subject, to adopt a Systematic Order ; to commence with the first genus of the arrangement, to go re- gularly through the species, then those of the next and following genera, and so on to the conclusion of the work. Thus the se- veral tribes woidd follow in correct order ; the first plates would represent the highest or the lowest type of organization, as cither was selected as a starting point, and those that followed would exhibit a regular gradation of affinity to the opposite end of the series. This is the course which, were the work to issue as a whole from the press, one would naturally follow ; but in an ex- tensive periodical work which it will take live years to complete, ADVERTISEMENT. VI) on a tribe of plants among which new species arc constantly being- discovered or added to the Flora, this plan is open, among others, to the grave objection that it forbids the introduction or early publication of new species, probably of much greater interest than those which it first illustrates. The second plan, and which, for many reasons I have adopted, is to select the species illustrated in each number from several different genera taken from as many families, so that there shall always be a variety of subjects in the monthly number ; and, as early in the work as possible, to figure one species at least of every genus, so that by the end of the twentieth number, which will complete the first volume, illustrations of all the genera may be placed before the student. This, with the aid of the descrip- tions of species and sketch of a general arrangement afforded by the " Manual " (which may serve as a Synopsis of the principal contents of the ' Phycologia '), wdl afford him very great facdities for determining his plants during the progress of this work, even though the particidar species which he has under examination may not be among those then figured in it. Were the plates to be pubbshed systematically, according to the first-mentioned plan, it is obvious that not till the completion of the entire work would the student have as much assistance toward understanding the genera as he will now have at the end of the first volume. This arrangement is therefore decidedly the best for those who have purchased the " Manual," and as it appears to me, for those also who, now commencing the study of Algology, wish to obtain speechly a general view of the principal varieties of marine plants. The main objection to this mode of publication is, that purchasers who wish to have their copies bound up in systematic order, must defer the binding till the whole is published. This is an incon- venience common to other similar works, to Smith and Sowerby's ' English Botany,' Greville's ' Scottish Cryptogamic Flora,' &c. ; but it is one which, in my judgment, is outweighed by other manifest conveniences. In concluding this Advertisement I take the liberty of soliciting ADVERTISEMENT. from all who feel an interest in the subject, such specimens of the rarer British Algae from all parts of the coast, as may serve to illus- trate either some peculiarity of growth, or throw light on distri- bution, or otherwise complete the history of the species. And I beg to assure such contributors, that it will always afford me pleasure to acknowledge their assistance, answer their queries, and communicate, in return, specimens which may be among then desiderata, W. H. 11. Trinity College, Dublin, Dec. 3rd, 1845. *>v^'^.V Ser. Melanospermete. Fam. Bictyotea. Plate I. DICTYOTA ATOMARIA, Grev. Gen. Char. Roof, a mass of woolly fibres. Frond flat, membranaceous, ribless, reticulated, dicliotomous or irregularly cleft. Fructification consisting of scattered or clustered somewhat prominent seeds on both surfaces of the frond. Dictyota atomaria ; frond broadly wedge-shaped, or somewhat fan-shaped, deeply and irregularly cleft longitudinally ; seeds forming waved trans- verse lines, with intermediate broken ones. Dictyota atomaria, Grev. Alg. Brit. p. 58. Hook. Br. Ft. vol. ii. p. 280. Wyatt. Alg. Damn. no. 60. Endl. ird Suppl. p. 24. Harv. Manual, p. 32. /. Ag. Alg. Medit. p. 37. Menegh. Alg. Ital. vol. i. p. 229. Dictyota zonata, Lamour. Es. p. 57. Dictyota ciliata, Lamour. Es. p. 58. Zonakia atomaria, Ag. Sp. Alg. vol. i. p. 128. Ag. Syst. p. 264. Grev. Fl. Edin. p. 298. Gray, Br. PI. vol. i. p. 341. Padina atomaria, Montag. Fl. Cai/ar. PI. Cell. p. 146. Padina phasiana, Bory, Fl. Pelop. p. 75. Stypopodium atomariiun, Kiitz. Phyc. Gen. p. 341. Ulva atomaria, Woodw. in Linn. Trans, vol. iii. p. 53. Eng. Bot. t. 419. Ulva serrata, BeCand. Fl. Fran. vol. ii. p. 1 1. Eneycl. Bot. vol. viii. p. 166. Hab. On marine rocks, rare. Annual. Summer. At Cromer, Mr. Wigg. Corton and Gunton, Mrs. Fowler. Worm's Head, Glamorganshire, Mr. Billwyn. Coast of Devon, Mrs. Griffiths. Sussex, Mr. Borrer. Frith of Forth, Br. Greville. Ballycotton, coast of Cork, Miss Ball. Geogr. Distr. West ladies, Lamouroux. Canary Islands, rare, Bespreanx. Mediterranean Sea, Agardh. German Ocean. Atlantic Coasts of France and Spain. Desc. Root, a broad mass of woolly, entangled, brown fibres. Fronds clustered, from 3 to 12 inches long, and from half an inch to 3 inches wide, delicately membranaceous, translucent, pale ohve-green above, becoming darker to- wards the base, glossy, broadly wedge-shaped, variously cleft from the apex downwards, sometimes very much jagged, never quite entire ; the lateral margins either entire or ciliato-dentate ; the tips of the laciniaj truncate. Seeds disposed in dark brown wavy transverse bands, running across the whole frond, at intervals of less than an inch, the spaces between more or less densely mottled with broken bues or irregular spots of seeds. This beautiful plant was discovered towards the end of the last century by Mr. Lilly Wigg, on the coast of Norfolk, and first published in the third volume of the Linnaean Transactions by Mr. Woodward, whose paper was read December 2nd, 1 794. In 1797 a figure of it appeared in the "English Botany," ' notwith- standing which in 1804 in the list of Spanish Algee appended to Clemente's " Essai sur les varietes de la vigne, " &c, and again in 1805, in De Candolle's 'Elore Francaise' we find two new names bestowed upon it. Since then, as will be seen from the above synonymes, (and we have not quoted all) authors have suffi- ciently exercised then fancy and invention in re-naming it. Of the newer names, Bory's "jphasiana " is the most appropriate, the brown bars on the frond reminding us of the plumage of a phea- sant, and coidd we with propriety adopt any, it would be this one. But in justice to the original describer, and following Agardli and most recent authors we adhere to the specific name under which it was first made known. Though widely distributed along the shores of the Northern Atlantic from the tropics to lat. 56° north, it is nowhere very common. Specimens from Dominica, given to me by Dr. Greville, are of a darker colour than British ones, and much more regularly banded, the broken bars, which generally cover the spaces be- tween the perfect bands, being very few. In England it is com- pletely a summer plant, reaching its perfection in Jidy and decay- ing before the end of September, at which season it has lost its glossy surface, rich colours, and much of its delicacy. Its re- mains are then coarse, almost coriaceous, dirty brown and ragged, and would scarcely be taken by a stranger to be the same species. While it agrees with others of the genus Dictyota in the struc- ture of the frond and in the fructification, it exhibits in general habit an approach to Padina, or perhaps more nearly to the re- stricted genus Zonaria, J. Ag., and has been referred by Mon- tagne as well as by Bory to the former genus. I admit that it is a transition species, especially resembling Padina in the banded arrangement of its seeds, but notwithstanding minor differences, the aggregate of its characters, in my opinion, compel us to refer it to Dictyota, unless with Kutzing, we cut the knot by construct- ing a new genus for its home. Fig. 1. Dictyota atomaria : — natural sine. 2. Portion of sorus. 3. Seeds in situ. 4. Seeds removed : — magnified. Ser. RhodospermejE. Fam. Delesserea. Plate II. DELESSERIA HYPOGLOSSUM, A g . Gen. Char. Frond rose-red, flat, membranaceous, with a percurrent mid- rib. Fructification of two kinds on distinct individuals ; 1, spherical tubercles (coccidia) immersed in tlie frond, and containing a globular mass of angular seeds ; 2, granules [tetraspores) forming defined spots in the frond, or in leaf-like processes. Delesseria Hypoglossum ; frond linear- lanceolate, tapering at each end, re- peatedly proliferous from the midrib, with leaflets of similar form ; tubercles on the midribs of the smaller leaflets; granules forming linear spots at each side of the midrib. Delesseria Hypoglossum, Ag. Sp. Alg. vol. i. p. 176. Sgst. p. 249. Grev. Fl. Edin. p. 293. Alg. Brit. p. 75. t. 12. Hook. Br. Fl. vol. ii. p. 286. Mack. Fl. Hib. vol. iii. p. 191. Han. Man. p. 56. Wyatt. Alg. Damn. no. 63. J.Ag.Medit.-p.Ul. Midi. 3rd Snppl. p. 52. Montag. Pl.Cell.Canar. p.150. Delesseria Hypoglossum, Lamour. Ann. Mus. xx. p. 124. Wormskioldia Hypoglossum, Spreng.Syst. Veg. vol. iv. p. 331. Hypoglossum Woodwardii, Kiitz. Ph.Gen. p. 444. t. 65. f. 1. Fucus Hypoglossum, Woodw. in Linn. Trans, vol. ii. p. 30. t. 7. Linn. Trans. vol. iii. p. 113. With. vol. iv. p. 95. Eng. Bot. 1. 1396. Turn. Syn. Fuc. vol. i. p. 17. Hist. 1. 14. Esp. Lc. Fuc. vol. ii. p. 17. t. 120. Fucus hypoglossoides, Stack. Ner. Brit. p. 76. t. 13. Ulva lingulata, Be Cand. Fl. Fran. 2nd edit. vol. ii. p. 14. Hab. In the sea, on rocks and Algae. Annual. Summer. Frequent on the shores of England and Ireland ; rare in Scotland. Geogr. Distr. Atlantic shores of Europe, frequent. Rare in the Mediterranean, and of small size. Canary Islands, Webb. Desc Boot, a minute disc. Fronds tufted, consisting of a primary leaf 2-8 inches in length, and from a line to half an inch in breadth, linear-lanceolate, rose- red and membranous, with a distinct midrib, and faint traces of obliquely transverse striae, throwing out from its midrib numerous similar leaves, which again produce others, until the plant becomes exceedingly bushy and of a globular figiue. The apices of the leaflets are more or less tapering or acute. If placed in fresh water the colouring matter is soon discharged. The tu- bercles are globose, forming a dark-red swelling in the substance of the mid- ribs of the smaller leaflets, generally about then crentre, and contain a large number of minute seeds ; and the granules form lineal patches along the midribs of the leaves of distinct, and generally more luxuriant, plants. Our figure, which represents a larger state of the plant than is commonly met with, though by no means the largest we have b 2 seen, is taken from a specimen collected by the late Miss Hutching in Bantry Bay. In that favoured locality and in other situations on the west coast of Ireland, and also at Larne near Belfast on the north-east coast, very luxuriant specimens are often met with in company with others as narrow and bushy as are commonly seen on the south coast of England. It varies indeed greatly in size, the frond being sometimes scarcely a line in width, some- times nearly half an inch ; but its admirable distinguishing cha- racter, that of being repeatedly proliferous from the midrib, is in- variable. The only British plant with which a young botanist can confound it, is the somewhat rarer D. ruscifolia, from which its thinner substance, brighter colour, proportionally narrower leaves, and the lanceolate, not linear-oblong, form of the leaflets distinguish it. The first notice of the species was by Dr. Solander who named a specimen in the Banksian Herbarium, the native country of which was unknown. Mr. Wigg having about the year 1794 found it on the Norfolk shores, it was published in the ' Linnaean Transactions,' as a British plant, and is now well known to occur in tolerable plenty on most of the European coasts. I have not seen any American specimens, nor is it found in the Southern Ocean. A species does indeed occur on several of the Antarctic Coasts, as at Auckland Island, Kerguelen's Land, Cape Horn and the Falkland Islands, which agrees in very many respects with D. Hypoglossum, having the same general habit, the same lanceolate leaves and the same proliferous growth ; but in it {I), cramnervia, Mont) the midribs of the leaves are usually very much broader and thicker. I fear, however, that tliis character is not a very constant one, some Falkland Island individuals having a much less broad midrib than others, or than the original Auckland spe- cimens, and I am almost disposed to regard the Southern plant as more properly a variety of the present species than specifically distinct. Fig. 1. Delesseeia Hypoglossum : — natural size. 2. Leaflet with tetraspores. 3. Section of ditto, showing part of the sorus. 4. Tetraspores separated. 5. Leaflet, with tubercles. 6. Section of ditto. 7. Tubercle removed. 8. Seeds from tubercle: — all magnified. /r /// Ser. Chlokosperme^;. Fam. Siphonece. Plate III. BRYOPSIS PLUMOSA, Jo. Gen. Char. Frond membranaceous, filiform, tubular, cylindrical, glistening, branched ; the branches imbricated or distichous and pinnated, filled with a fine green, minutely granuliferous fluid. Grev. Bkyopsis plumosa ; frond having a triangular outline, naked below, branched above, branches spreading, their upper half pectinato-pimiated, pin- nules subdistichous. Bryopsis plumosa, Ag. Sp. Alg. vol. i. p. 448. Syst. p. 178. Grev. Fl. Edin. p. 307. Alg. Brit. p. 187. t. 19. Hook. Br. Fl. vol. ii. p. 318. Han. Man. p. 146. Wyatt. Alg. Damn. no. 128. J. Ag. Alg. Medit.ip.2l. Endl. 3rd Suppl.-p.20. Mart. Fl. Bra;, vol. i. p. 11. Kid;. PL Gen. p. 306. Bryopsis Lyngbya?i, Fl. Ban. t. 1063. Byngb. Hyd. Ban. p. 75. 1. 19. Spreng. Syst. Veg. vol. iv. p. 365. Ulva plumosa, Huds. Fl. Aug. p. 571. Fng. Bot. t. 2375. Hab. In the sea, on rocks and small stones. Annual. Summer and Au- tumn. Frequent on the shores of the British Islands. G.EOGR. Distr. Aloug the Atlantic shores of Europe from the Eseroe Islands to Spain. Mediterranean Sea, /. Agardli. South Brazil, Martins. Falkland Islands, Br. Hooker. Cape of Good Hope, W. H. H. Desc. Root composed of irregular entangled filaments. Fronds several from the same base, at first perfectly simple, straight and thread-like till they become half an inch to an inch in length, at which period they commence to form lateral branchlets in the upper half. In this state the whole plant resembles a little feather. Afterwards the naked part of the stem lengthens, and its ramuli grow out into branches 1-3 inches long and about half a line in diameter, producing, by a repetition of the primary mode of growth, several series of lesser branches, until a much branched frond results. Then, owing to the lower branches being long, and the upper gradually diminishing to the summit, the general outline is triangular or pyramidal. In every stage, however, the branches, naked below and feathered above, afford a sufficiently distinguishing character. The substance is exceedingly glossy, flaccid, and easily injured, and the colour a rich deep green. Each branch consists of a sin°ie cellule, and on wounding the outer membrane discharges its contents in the form of a granular thick fluid. In drying it adheres most closely to paper, and has a varnished appearance. A very widely distributed plant found plentifully throughout both the temperate zones, and even in some of the warmer seas. It is perhaps also a native of the tropics, the West Indian B. pen- nata of Lamouroux, being possibly a synonyme. Be this as it may, species of Bryopsis have been found in all parts of the world,' and they resemble each other so closely, that except in a few instances it is very difficidt at all times to determine to what particular book species individuals should be referred. Though having all the softness of texture and brilliant green colouring of the Conferva, the Bryopsides must be regarded as holding a still lower rank in the Vegetable Kingdom, and ap- proaching very nearly to those organisms that seem uncertain under which banner to arrange themselves, whether Animal or Vegetable. Viewed by itself indeed Bryopsis plumosa appears as perfect a vegetable as any, but taken in connection with neigh- bouring nearly allied structures Basyeladus, Caulerpa, Pohjphysa, Halimcda, Struvea, &c, it is foimd to approach much more closely to the confines than would at first sight be supposed. The first notice we find taken of this elegant plant is by Hudson in whose 'Flora Anglica' it appears under the specific name by which it is most generally known. Fig. 1 Bryopsis plumosa -.-^natural she. 2. Branch. 3. Apex of ditto 4. Section of branch and ramulus : — all magnified. PlaZe IT. Ser. MelanospermejE. Fam. Fctocarpea. Plate IV. ECTOCARPUS BRACHIATUS, Han. Gen. Char. Filaments capillary, jointed, olive or brown, flaccid, single tubed. Fruit ; either spherical, elliptical, or lanceolate capsules borne on the raniuli, or imbedded in their substance. Ectocarpus brachiatus; frond finely tufted, feathery, much branched; the branches free, opposite or quaternate ; raniuli opposite, spreading ; cap- sules imbedded in the branches, forming oblong swellings situated on the lesser branches or in the axils of two opposite ramuli. Ectocarpus brachiatus, Harv. in Hook. Br. Fl. vol. ii. p. 326. Man. p. 42. TTyatt. AJg. Damn,, no. 174. Ectocarpus cruciatus, Ag. Sp. Alg. vol. hi. p. 44. Endl. 3rd Suppl. p. 21. Conferva bracliiata, Eng.Bot. t. 2571. Hab. Bare. At Cley, on the coast of Norfolk, in ditches of brackish wa- ter, among Fnteromorpha eompressa, 1808, Sir W. J. Hooker ; in the sea, growing on Rhodomenia palmata, at Torquay, Mrs. Griffiths. Toughall, July 1837, Miss Ball. Lambray, 1838, Mr. W. Thompson. Geogr. Distr. Only known on the coast of England, and east and south of Ireland. Desc Frond 2-4 inches high, finely tufted, wavy and feathery ; the main stems slightly entangled, excessively branched, all the branches and hranchlets opposite or quaternate ; the lesser branches generally naked below, but fur- nished in their upper half with one or two pair of opposite spreading ramuli, which are in like manner furnished with similar smaller ones. Cap- sides immersed in the joints of the branches, often containing a double or bipartite mass, usually situate at the nodes of the branchlets. Colour a pale olive green. There is some confusion in the history of this plant, which is one reason why I give it an early figure in this work. In the year 1801, Mr. Dawson Turner, and in 1808, Sir W. J. Hooker, found in ditches of brackish water by the sea side on the Norfolk coast a plant of which a figure and description appeared in the 'English Botany' under the name of Conferva bracliiata. That figure evidently represents a species of Ectocarpus, having opposite branches and immersed fruit. The Norfolk plant has not been foimd of late years, and no specimen now exists in Sir W. J. Hooker's Herbarium. The English Botany plate consequently re- mained for many years the only record of the species, untfl Mrs. Griffiths discovered in Torbay a plant possesing apparently the leading or essential characters of the Norfolk one, but growing in the open sea and always as a parasite on Bhodomenia palmata. Meanwhile Agardh described a new Ectocarpus brachiatus, a native of the Baltic, and conferred the name E. cruciatm on the E. Bot. species. The name brachiatus no doubt belongs to the Norfolk plant, and if the Torbay individuals now figured and described, and of which excellent specimens have been published in Mrs. Wyatt's " Alga Danmonienszs " are essentially different, a new name should be conferred on them ; and Agardh's E. brachiatus, if it be not the same with E. spkarqpAorus, Carm., might be called E. Agardhianiis. Fig. 1. Ectocaupus brachiatus : — natural size. 2. A portion of the frond : — magnified. 3. Apex of a branch. 4. Fragment, to show the imbedded fruit : — more tiiijhli/ magnified. PlaZi V. Ser. Rhodosperme.e. Tarn. Ceramiea. Plate V. CALLITHAMNION GRACILLIMUM, A 9 . Gen. Char.. Frond rosy, or brownish red, filamentous ; stem either opake and cellular or translucent and jointed ; branches jointed, one-tubed, mostly pinnate (rarely dichotomous or irregular) ; dissepiments hyaline. Fruit : 1, external tetrasjiores, with colourless borders, scattered along the ultimate branehlets or borne on little pedicels; 2, roundish or lobed berry-like receptacles {favetta), seated on the main branches, and containing numerous seeds. Callithaknion gracillhnum ; frond distichously branched, fan-shaped; stems capillary, decomposito-pinnate ; upper plumules long, narrow, ovate or lanceolate, spreading, bi-tri-pimiate ; joints of the stem cylin- drical, three or four times, of the pinna? two or tliree times longer than broad, veinless ; tetraspores borne on the tips of the pinnules. Callithamnion gracillimum, Ay. Sp. Alg. vol. ii. p. 168. Han. in Hook. Br. Fl. vol. ii. p. 345. JFi/att. Jiff. Banm. no. 45. Midi. ZrdSuppl. p. 34. Kiitz. Fliyc. Gen. p. 372. Hab. Very rare. On mud-covered perpendicular rocks, near low- water mark. Annual. Summer. On the pier at Torquay, Mrs. Griffith*. Milford Haven, Mr. Rolfs. Falmouth, Miss Warren. Geogr. Distr. Atlantic coast of France, Grateloup. South and west of England. Desc Fronds tufted, 1-4 inches high, exceedingly slender, distichous, irregu- larly branched ; main branches rather few, simple, 1-2 inches long, un- equally but closely plumulate along their whole length, having an ovate or lanceolate figure, aud all attenuated at the point. Lower plumules short, vaguely pinnate ; upper elongate, lanceolate, spreading, bi-tri-pinnate. All the divisions alternate, and a branchlet usually springing from every joint. The colour, when quite recent, is a deep red, becoming rose-red in fresh water, and if kept long in that medium the frond discharges a quantity of brilliant carmine powder, which permanently stains paper. Tetraspores very minute, elliptical, borne on the tips of shortened pinnulas. Favella roundish or irregularly lobed, springing from the larger branches. Substance deli- cately membranaceous and flaccid, closely adhering to paper. This extremely elegant plant, perhaps truly the most graceful of the very beautiful genus to which it belongs, was first gathered on the shores of France by M. Grateloup, who communicated specimens to the elder Agardli, by whom it was published in the year 1828. Shortly afterwards the indefatigable Mrs. Griffiths c discovered magnificent specimens growing along the mud-covered base of the harbour pier at Torquay, in which locality it may be found in more or less plenty every summer. More recently it has been found in Wales and Cornwall. From Mrs. Griffiths it received the very appropriate name of " Fern-leaf" aptly express- ing the finely pinnated character of the branches, which do indeed closely resemble fairy ferns, so delicate that it is altogether impos- sible in a figure to do justice to their beauty. Our representation of the natural size must therefore be regarded as merely giving the general effect of a specimen held at arms length from the eye. As a species, it is very closely related to Cal. thuyoideum; with which it agrees in many characters, but from which it may be known by the greater proportionate length and breadth of the plumules, their more distichous arrangement and closer position ; the shorter and more cylindrical joints of the main branches, and larger size of the frond. Both species agree in producing their tetrasjmrcs on the tips of the ultimate raniuli, a character by which they differ from all other British species with decom- pound-pinnate fronds. Fig. 1. Cailithamnion geacillimum : — natural size. 2. A plumule : mag- nified. 3. Hamulus with tetraspores. t. Hamulus with a favella. 5. Portion of a favella ruptured, and discharging seeds 6. Tetraspores removed and dissected : — all more or less magnified. Ser. Ciilorosperme.e. Fain. Ctmfervea. Plate VI. CLADOPHORA LANOSA, mtz. Cen. Char. Filaments green, jointed, attached, uniform, branched. Fruit; aggregated granules or zoospores, contained in the joints, having, at some period, a proper ciliary motion. Cladophora lanosa ; Filaments slender, short, yellow green, form i no- dense globular tufts ; branches virgate, erect, subdistant, straight, alternate or rarely opposite ; ramuli few, alternate or secund ; axils very acute ; lower joints twice, upper six times, as long as broad. Cladophora lanosa, Kiitz. Phyc. Gen, p. 269. Conferva lanosa, Roth. Cat. Bot. vol. iii. p. 291. t. 9. Sni.E. Bot. t. 2099. Lyngb. Hyd. Ban. p. 160. t. 56. Billw. Conf. t. E. Ag. Syst. Jig. p. 112. Greo. Ft. Edin. p. 316. Hare, in Hook. Br. El. vol. ii. p. 358. Man. p. 138. Wyatt. Alg. Danm. no. 194. Hab. In the sea, on rocks, or, more frequently, on the larger Fuci. Fre- quent on the shores of the British Islands. Geogr. Distr. Northern Atlantic shores of Europe. Baltic sea. Desc. Tufts 1-2 inches in diameter,, globose, made up of innumerable slender entangled filaments radiating from a centre. Filaments stoloniferous below, or sending out, here and there, irregular root-like imperfectly jointed pro- cesses ; branches few, straight and erect. Joints of the lower part of the filament short, once or twice as long as broad ; those of the upper branches very long. When dried on paper, to which it adheres more or less closely, it is wholly without gloss, and faded to a whitish green, except round the circumference where it usually retains a glaucous or verdigris colour. The endochrome is very fluid and not well preserved in drying. This plant is found in abundance on most of the Atlantic shores of Europe, inhabiting the old stems of Fucus serratus and F. ve- siculosa, the leaves of Zostera marina, and occasionally, but far less frequently, growing on submarine rocks and stones. It is decidedly found in greater perfection and abundance as we pro- ceed northwards, and on the west coast of Scotland the finest specimens we have seen are gathered. From one of these, col- lected by the late Capt. Carmichael, our figure is taken. Dr. Roth first described his Conferva lanosa in the third part of his 'Catalecta Botanica,' published in 1806 ; and soon afterwards Mr. Dillwyn introduced it to the notice of British Botanists in the Supplement to his work on Conferva?. It does not appear to have been noticed by earlier writers. It is very closely related to C. a rein and C. uncialis, from the former of winch it differs chiefly by its smaller size and less branching filaments, and from the latter more by habit than by any very decided characters. The so- called species of the genus Cladophora ought, in many cases, to be regarded more properly as tolerably constant forms or varieties, than truly distinct organisms ; but as similar doubts of the vali- dity of species encumber the nomenclature of plants far higher in the system, we may the more readily tolerate them here. The proper time has, perhaps, arrived for dismembering the old genus Conferva, Ag., as proposed by several continental authors and carried out in this country by Mr. Hassall in his " Fresh-water Alga?." Kiitzing, whose name Cladophora I here adopt (although in strict justice Chhroniton, Gail!., ought to be preserved), dis- tributes the Agardhian Conferva? into twelve genera, six of Avhich only concern the British Flora. Of these (Edogonium, Link, is identical with Mr. Hassall's Vesical if era, and with the still older Tiresias, Bory, which latter name should be adopted. Conferva is retained for the species' with simple threads, whose fruit is im- perfectly known. Rhizogonium is proposed for Conf. riparia, Ag., and its allies ; while JEgagropila, founded on C agagropila and Spongomorpha, on C. uncialis, I include in the genus now called Cladophora. It woidd be clearly a most artificial arrangement to separate C. uncialis generically from C. lanosa and C. arcta. Fisr. 1 ■ Cladophora lanosa : — natural size. 2. Portion of a filament 3. Por- tion of the lower part of a filament. 4. Apex of ditto : — magnified. /'//. Ser. Rhodospersie.e. Fam. Rhodomelete. Plate VII. POLYSIPHONIA FURCELLATA, Haw. Gen. Char. Frond filamentous, partially or generally articulate ; joints lon- gitudinally striate, composed internally of parallel tubes or elongated cellules. Fructification twofold, on distinct plants : 1, ovate capsules (ceramidia) furnished with a terminal pore, and containing a mass of pear-shaped seeds; 2, tetraspores imbedded in swollen branchlets. Polysiphonia — from irokis, many, and o-tyav, a tube; because the axis of the frond is composed of several tubes. Polysiphonia furcellata ; filaments elongated, tufted, fiexuous, repeatedly and closely dichotomous ; axils broad, rounded; ramuli erect, their points somewhat hooked in ; joints of the stem three to five times longer than broad. Polysiphonia furcellata, Earn, in Eook. Br. M. vol. ii. p. 332. Man. p. 90. Mtmtag. PL Cell. Canar. p. 172. Endl. 3rd Suppl. p. 45. Kiitz. Ph. Gen. p. 425. Hutchinsia furcellata, Ag. Sp. Alg. vol. ii. p. 91. Lamourouxia turgidula, Bonnem. MSS. sec. Ag. Hab. Very rare. Moating in the sea, at Sidmouth, Mrs. Griffiths and Miss Cutler. Dredged in Torbay, Mrs. G-riffiths. Carrickfergus, Mr. W.irCalla {1Mb). Annual. Summer. Geogr. Distr. Atlantic shores of France, Messrs. Bonnemaison and Chauvin, sec. Ag. South shore of England. Canary Islands, Webb. North-east of Ireland. Desc. Filaments as thick as hogs bristle in the lower part, gradually attenuated, 5-6 inches long, densely tufted and frequently much entangled, excessively branched, fiexuous or zig-zag, the divisions pretty regularly dichotomous, the lower ones subdistant, the upper gradually becoming nearer to each other towards the extremities. Axils all remarkably wide ; apices either straight and subulate, or hooked in ; at first simple, finally producing byssoid fibres from all the upper articulations. Stem composed of about eight tubiform cells surrounding a narrow central tube ; walls of the cells thick, endochi'ome comparatively narrow. Articulations varying in length in different parts of the frond ; those of the larger branches 3-5 times, of the lesser about twice, and of the ultimate ramuli as long as, or shorter than, then breadth. Colour when recent, " a bright brick-red," which changes in the herbarium to a deep umber-brown. Substance, according to Mrs. Griffiths, " at first firm, but becoming flaccid immediately." Capsules unknown. Tetraspores fre- quently occur in British specimens. I have here the satisfaction of figuring for the first time a species as rare as it is beautiful, which, till it was recently brought by Mr. Webb from the Canary Islands, was supposed to be con- fined to the shores of the British Channel. It was first noticed on c the coast of Bretagne by M. Bonneinaison; and added to our Flora by Mrs. Griffiths in 1827, who gathered it freely floating in the sea opposite Sidmouth. In that locality and in Torbay it has, since that period, occasionally been picked up, but the supply is neither regular every year, nor at any time has it been abundant. Whilst this sheet was preparing for the press Mr. M'Calla dis- covered a new station at Carrickfergus, in the north-east of Ireland, where he obtained three specimens, one of which is of the average size of English specimens, and fully developed, the other two in a young state. These were washed on shore in October 1845, in company with a considerable quantity of the rare Pol. suhuli- fera and of Chorda ria divaricata, Ag., a species new to the British Flora, which we shall have the pleasure of figuring in our next number. There is no British species so nearly allied to P.furcellata as to be confounded with it, although when examined microscopi- cally we perceive a considerable affinity on the one hand to P. nigrescens, and on the other to P.fastigiata. Between these two species indeed, P. furcellata appears to me to be almost inter- mediate. The relative length and the structure of the joints are very much those of P. nigrescens, from which the dichotomous, not pinnate, ramification, the want of leading stem, bright colour, &c., abundantly distinguish it ; while, on the other hand, the ramification nearly approaches that of P '. fastigiata ; but then, the nature of the joints, the colour, and the flaccid substance are very different. There is another species which ought to be here noticed as being closely related to P.furcellata, namely, P. corgmbifera, a native of the Cape of Good Hope. This, if my specimens are correctly named, is a more robust plant, with more distant dicho- tomies, more acute axils, and remarkable for its densely corym- bose fastigiate multifid lateral branchlets, and the number of tubes contained in the stem is twelve or thirteen. It has, how- ever, very much the habit of a Luxuriant specimen of P. furcellata, and though truly distinct, by the above mentioned and some other minor characters, might easily, on a hasty inspection, be mistaken for that species. Fig. 1. Polysiphonia furcellata: — natural size. 2. Branehlet. 3. Section to show the different lengths of the joints. 4. Ramulus bearing tetraspores. 5. A tetraspore (undivided?) removed. 6. Fibruliferous apex. 7. One of the nbrillae. 8. Transverse section of the stem: — all magnified. Piatt nil. 6 / -*P. n * * 4 Ser. Melanosperme.e. Fam. Bxctyotea. Plate VIII. PUNCTARIA LATIFOLIA, Greo. Gen. Char. Frond undivided, membranaceous, flat, ribless, with a naked, scutate root. Fructification scattered over the whole frond in minute distinct dots, composed of roundish prominent seeds intermixed with club-shaped filaments. Punctaria — from pumbwm, a dot; the fruit being in dots, scattered over the surface. Punctaria latifolia ; frond oblong or obovate, suddenly tapering at the base, pale olive green, thickish, gelatinous and tender. Punctaria latifolia, Grev. Alg. Brit. p. 52. Hook. Br. Fl. vol. ii. p. 278. Mack. Fl. Hib. vol. iii. p. 176. Han. Man. p. 33. Wyatt. Alg. Damn. no. 9. /. Ag. Alg. Medit. p. 41 . Eitdl. 3rd Suppl. p. 25. Meneg. Alg. Ital. p. 174. Phycolapathum debile, Kiitz. Phjc. Gen. p. 292. t. 24. II. (in part). Hab. Bocks and stones in the sea. Annual. Summer. Sidmouth and Torquay, 31ns. Griffiths. Near Belfast, Dr. Drummond. Islay, Mr. Chalmers. West of Ireland, frequent, W. H. H. Geogr. Distr. British Islands. Mediterranean sea, in several places, /. Agardh. Trieste, Herb. Hooker I Desc Root, a flat naked disk. Fronds generally forming large tufts, 8-16 inches lono-, 1-3 inches wide, oblong or lanceolate, flat or more or less curled or wavy, generally obtuse at both extremities, occasionally tapering, when in perfection delicately membranaceous, semitransparent and somewhat gela- tinous, but becoming in advanced age thicker and coarser, always of a very pale olive-oreen colour. Dots of fructification minute, roundish, thickly scattered over both surfaces. It closely adheres to paper if gathered in an early or middle stage of growth, but specimens collected later in the year will' not adhere to paper in drying. This species was founded in 1839 by Dr. Greville, in his ad- mirable 'Algae Britannicse,' on specimens communicated by Mrs. Griffiths and Dr. Drummond, and has since been detected in tolerable plenty on several of our coasts. It is probable that by earlier botanists it was confounded with P. plantaginea, to which some of its varieties make a near approach in form, and with which it is often found associated in the same pool. I have specimens of both species gathered side by side by Mrs. Griffiths, who observes, that " P.plantaginea is much thicker than P. lati- c 2 folia, the meshes of the reticulations longer, and the dots of fructification more oblong." " It is much easier," adds this acute observer, "to see the difference than to describe it in words." The most obvious difference lies in the colour ; — P.plan- taginea being of a clear dark brown ; P. latifolia always very pale. P. plantaginea also is usually much narrower, and greatly more tapering, truly cuneate at the base, and much less wavy ; but I possess specimens as broad and as little tapering below as many referred to P. latifolia. Nor am I very confident, after an attentive comparison of a multitude of specimens, whether there is any absolutely distinguishing character between the two except colour, if that be admitted as sufficient. Late in the season P. latifolia becomes as coarse and tluck as P. plantaginea, and will not in the least adhere to paper. A specimen, from Trieste, in Sir W. J. Hooker's herbarium is identical with those from Devon- shire ; but Dr. J. Agardh states that his Mediterranean specimens are thicker than British ones : it is therefore obvious that the substance varies as much in the Mediterranean as I have observed it to do in our seas. The genus Punctaria is exactly analogous among Dictyotese to Utva in Ulvacese, and so closely do its species resemble the Ulvae in form and substance, that without reference to fructification, or without a close examination of the structure of the frond, a young botanist might sometimes confound the species of one genus with those of the other. It requires also a careful examination to distinguish at all times between Laminaria debilis and Punc- taria latifolia, the form and colour of both being nearly identical. The Laminaria is, however, to the naked eye, more glossy and adheres much less firmly to paper ; and its structure, instead of being reticidated is closely cellular. Pig. 1. Punctaria latifolia : — natural size. 2. Base of the frond and scutate root ; — magnified. 3. Portion of the frond, showing the reticidated struc- ture, and spots of fructification, vertical view ; — magnified. 4. Sorus, lateral view ; — magnified. FlaJke, 11. MB §8 ^m Ser. RhodospermEjE. Fam. Delesseriea. Plate IX. NITOPHYLLUM VERSICOLOR, Haw. Gen. Char. Frond membranaceous, reticulated, rose-red (rarely purplish), irregularly cleft, veiuless, or famished with irregular veins toward the base. Fructification, two-fold, on distinct plants : 1, spherical tuber- cles (coccidia) immersed in the frond, and containing a globular mass of angular seeds ; 2, letraspores grouped into definite sori or spots, variously scattered over the frond. Nitophyllum — corruptly formed from niteo, to shine, and iXkov, a leaf; shining-leaf. Nitophyllum versicolor ; stem cartilaginous, elongated, simple or branched, suddenly expanding into a broadly fan-shaped, variously cleft frond, of a thickish-membranaceous, highly reticulate substance and rose- red colour, becoming golden-orange in fresh water; the segments rounded ; the apices generally thickened, and ciliiferous ; fructification unknown. Nitophyllum versicolor, Earn. Manual, p. 59. Hah. Very rare. Thrown up, probably from deep water. Annual. June to August. Ilfracombe, Miss Hill (1800) and. Mrs. Griffiths. Youghal, Miss Ball (1834). Geogk. DisTtt. Southern shores of England and Ireland. Desc. Boot unknown. Stems irregularly tuberous or incrassated below, from half au inch to an inch long, fleshy, firm, cylindrical or club-shaped, 1-2 lines thick, simple or branched. The branches suddenly expand into broadly fan-shaped fronds 2-3 inches in breadth, and l-§--2 inches in height, more or less deeply cleft in a dichotomous manner, membranaceous and veinless. Segments in some specimens less than half an inch broad, in others above an inch, cuneate, now once or twice cleft, now many times divided, roundish at the apices, entire or minutely ciliate. The tips of the frond, and some- times portions of the lateral margin, are much thickened, producing oblong or oval fleshy excrescences something similar in appearance to the thick- ened base of the stem. These calli are in an early stage minutely papillate, especially towards the outer edge (fig. 6), but as they advance in age the papillae elongate into irregularly branched, cellular, cylindrical filaments (fig. 5, 9, 10). On cutting open the callus innumerable minute granules, re- sembling those which constitute the solid part of the endochrome of the cells, issue forth, but these bear no resemblance to spores of any description. The substance of the frond is thicker, and the reticulations, shown at fig. 4, larger than in N. Bonnemahoni, to which species the present is nearly allied. The colour when fresh is a rosy-red, but the slightest contact with fresh water changes this to a golden-orange. On drying, however, the original colour is restored, and is retained in the herbarium. The substance is softer than in N. Gmelini, and in drying the plant adheres more firmly to paper. I have little to add to the account of this species already pub- lished in the Manual, except it be to record the discovery, by Miss Ball in the south of Ireland, of remarkably luxuriant specimens, from one of which the uppermost figure in our plate has been drawn. Miss Ball's first specimens were gathered in 1834, and she obtained further supplies in 1840 and 1844 : — but as all these, like the Devonshire plants, were washed on shore, the habitat of the species remains unknown. By a recent communication from Mrs. Griffiths I learn that it was Miss Hdl, and not Mrs. Hare, who was the original disco- verer of this species in 1800 ; but it appears to have been known to the latter lady shortly afterwards, and called by her Fi/cus Halensis. To Mrs. Griffiths it has been familiar for thirty years under the colloquial name " Orange Dwarf," which at once ex- presses its usually small size, as compared with others of the genus, and the rapid change of colour which it undergoes on touching fresh water. The last peculiarity is so striking that a passing shower of rain has often betrayed it to Mrs. Griffiths, when before the shower it had passed unnoticed among other red plants. Dr. Greville in his ' Cryptogamic Flora ' considers it identical with N. Bonnemaisoni, an opinion which he subsequently aban- doned; and in his Alga Britannica he refers it to N. Gmelini. I agree with Mrs. Griffiths in judging it to be distinct from both these species, at the same time admitting that it borders very closely on both, and that in the absence of a knowledge of its fructification it is difficult to fix on a very tangible distinguishing character. I have endeavoured, in the accompanying plate, to detail all its known characters. Among these it is impossible to overlook the anomalous, but very constant, production of colli, giving birth to branching filaments, totally unlike the usual form of proliferous growth ; as certainly not parasitical ; neither, so far as we know, having relation to fructification. And yet it must be confessed that they bear a near resemblance to the fructiferous processes of the singular Australian genus Hetero- cladia of Decaisne. It would be a highly curious and interesting discovery should tetraspores ever be found on these processes in the present species. Fig 1 2 3 Nitophyllum versicolor, different varieties : — natural she. 4. Portion of the frond, to show the structure. 5,6. Apices, producing calk. 7. Section of a callus. 8. Grannies filling its canty. 9, 10. Ciliae of the callus : — all more or less magnified. FLaJbt X - iro.p ; Ser. Rhodospermejs. Fam. Rhodmnelea Plate X. POLYSIPHONIA RICHARDSONI, Hook. Gen. Char. Frond filamentous, partially or generally articulate; joints longitudinally striate, composed internally of parallel tubes or elon- gated cellules. Fructification two-fold, on distinct plants ; 1, ovate capsules (ceramidia) furnished with a terminal pore, and containing a tuft of pear-shaped seeds ; 2, tetraspares imbedded in swollen branch- lets. Polysiphonia — from nokvs, many, and o-tyav, a tube ; because the axis of the frond is composed of many tubes. Polysiphonia Richardsoni ; stems cartilaginous, setaceous; branches alter- nate, elongated, divaricate, beset in the upper part with very patent, straight, sub-dichotomous raniuli; articulations of the stem and branches two or three times longer than broad, irregularly veined ; of the ramuli shorter ; capsules sessile, globose. Polysiphonia Kichardsoni, Hook. Br. Ft. vol. ii. p. 33. Ran. Man. p. 90. Hab. Very rare. At Colvend, Dumfries, Dr. John Richardson. Geogr. Distr. South-west of Scotland. Desc. Root scutate. Frond 3-4 inches long, setaceous, rather rigid, with a subdistinct, zig-zag stem, very much branched from a short distance above the base ; the branches issuing at right angles, angularly bent, as long as the main stem, subquadrifarious, mostly alternate, beset with distant, very patent, subdichotomous, straight branchlets, which bear a few mostly sim- ple, erecto-patent or erect, subulate ramuli. Articulations visible in the main stem, subtorulose, the lower ones three or four times longer than broad, spirally or irregularly tubed ; the upper shorter, with parallel tubes. Capsules globose, sessile, wide-mouthed, situate near the summits of the lesser branches. Tubes about five in the stem, each with a deep-coloured bag of endochrome. What little is known of this species, if it be entitled to that rank, is taken from a specimen gathered by Dr. Richardson many years ago, before the Arctic Expedition which he accompanied, and preserved in Sir W. J. Hooker's rich Herbarium. Our upper- most figure is nearly a fac-simde of that specimen. Though it closely borders in its microscopic characters on several species, its habit does not precisely agree with any with which I am acquainted. The nearest in affinity is perhaps P. fibrillosa, and it is possible that it may be only an anomalous form of that very variable species, from the normal state of which its clearly articulate stem affords a ready distinctive character. The habit of branching strikingly reminds us of P. elongella, but iu no other character does it agree with that species. There is also an affinity with P. violacea and P. Jibrata, and especially with P. Grrffitlmana ; but from all these it differs in more or less degree, and with none, except the last, has it a very strong relation. With the view of attracting the attention of collectors to the subject, and thereby clearing up the doubts which I cannot help entertaining respecting the validity of the species, I have given it an early figure. Nothing is known respecting the manner or place of its growth, but very probably it is a parasite on some of the smaller Algae ; and most likely an annual, and found in the summer season. Fig. 1. Polysiphonia Eichakdsoni : — natural she. 2. Apex of a branch: — magnified. 3. Portion of the stem. -A. Portion of an upper branch. 5. Transverse section of the stern. 6. Capsule or ceramidium: — all more or less magnified. i $m Xfc/- r , % * Ser. Melanospermejs. Fain. Vicfyotece. Plate XI. ASPEROCOCCUS TURNERI, Hook. Gen. Char. Frond imbranched, tubular, cylindrical or rarely compressed, inflated, continuous, membranaceous. Root naked, scutate. Fruelijiai- tion scattered over the whole frond, in minute, distinct dots, composed of roundish, prominent seeds, intermixed with club-shaped filaments. Asperococcus — corruptly formed from asper, rough, and kokkos, a seed ; because the dots of seeds are mixed with bristle-like filaments. Asperococcus Turneri ; frond inflated, cylindrical, obtuse, oblong or club- shaped, suddenly contracted at the base into a short stem, thin and membranaceous ; dots of fructification minute, roundish. Asperococcus Turneri, Hook. Br. M. vol. ii. p. 277. TFgatt. Alg. Damn. no. 59. Harv. in Mack. Fl. Hib. part 3. p. 175. Han. Man. p. 34. Asperococcus bullosus, Lamour. Ess. p. 62. t. 6. f. 5. Grev. Alg. Brit. p. 51. Midi. 3rd Suppl. p. 26. /. Ag. Alg. Medit. p. 41. Menegh. Alg. Ital. et Balm. p. 166. Asperococcus rugosus, /3 bullosus, Bub. Bot. Gall. vol. ii. p. 956. Encelium bullosum, Ag.Sp.Alg. vol. i. p. 146. Sy&t. p. 262. Spreng.Sgsl. Veg. vol. iv. p. 328. Kiitz. Pligc. Gen. p. 326. t. 21. f. 1. Gastridium opuntia, Lgngb. Hyd. Ban. p. 71. t. 18. Ulva Turneri, Billw. — . Bug. Bot. t. 2570. Hab. In the sea, on stones and the larger Algse, on Zostera, &c, often growing in 4-5 fathoms. Annual. Summer and Autumn. Coast of Sussex, Mr.Borrer. Devonshire, Mrs. Griffith. Bantry Bay, Miss Hittcfiins. Appin, Capt. Carmichael. The " Murrough " at "Wicklow, W. H. H. (1833). Strangford Lough and Clew Bay, Mayo, Mr. W. Thompson. Iioimdstone Bay, Galway, Messrs. IF. Thompson, R. Ball, and E. Forbes (1840). Howth. Miss Ball. Ireland's Eye and Lambay, Mr. R. Ball. Abundant on the Kerry Coast, Mr. W. Andrews. Dingle and Valentia, W. H. H. Jersey, Miss White. Geogr. Distr. Atlantic coast of Europe, from Norway (Lgngb.) to Spain! Baltic Sea. Mediterranean and Adriatic Seas. Southern Ocean, Ago nil. Desc Root a minute scutate disc. Fronds commonly from 6 to 12 inches in length, and from half an inch to an inch and a half in diameter, but occasion- ally 16 to 42 inches in length and from 2 to 4 in diameter, suddenly con- tracted at the base into a thread-like stem, which varies from a to a an inch in length, inflated, bag-like, and of nearly equal breadth throughout, sometimes club-shaped, very obtuse, here and there occasionally contracted, delicately membranaceous and subtransparent, pale olive or inclining to fawn colour. When young the frond is greenish olive with a soft and sub- gelatinous feel and adheres to paper, but older specimens are harsher, of rather thicker substance, and will not adhere to paper in drying. Dots of fructification very minute, roundish or oblong, sometimes confluent, densely scattered over the surface, composed of dark-coloured, elliptical spores lying on the surface of the frond, among which, in greater or less D abundance, spring short, simple, or slightly branched, jointed filaments. The structure of the membrane, as shown at fig. 3, is very beautiful. The outer surface of the frond is composed of slightly inequilateral, 4- or 5 -sided cells with thick walls, and containing a granular, pale-olive endochrome. These are internally strengthened by a lattice-work which lines the whole frond, whose meshes are 12-16 times as large as the cells of the membrane. We are not informed by whom this species was first observed. The honour rests between Miss Hutchins and Mr. Borrer, by each of whom it was found in different localities early in the present century, and named, by Dillvvyn, in honour of Mr. Dawson Turner, the distinguished author of the ' Historia Fucorum' Unfortu- nately Mr. Dillwyn delayed for several years the publication of the species, and it first appeared under this name in the volume of English Botany for 1813 ; in which same year, Lamouroux, unaware of the long-conferred manuscript name, published it as a new species, conferring upon it the specific name bullosas, by which it is still universally known on the continent. It is a question which specific name has the priority in publication, and in an ordinary case I should feel bound to follow the majority — who have decided in favour of bullosas, — but I am unwilling, without better grounds, to deprive the Father of modern Phycology of a well-merited compliment; and I therefore follow Hooker in retaining the specific name earliest proposed — -though not pub- lished. Asperococcus Turneri appears to delight in land-locked muddy bays, where it grows to the gigantic size mentioned in the des- cription. Specimens upwards of three feet in length, have been dredged by Mr. Thompson in Strangford Lough. I have seen individuals not much inferior in the little harbour of Dingle, and in the long, deep channel which divides Valentia from the main- land. When growing in deep water its favourite habitat is on the stems and leaves of Zostera. Specimens gathered within the tide range are of much smaller size, not more than a few inches in length. Except in size it is subject to little variation. It may always be known from A. echinatus by its greater delicacy of texture, more evident reticulations, paler colour, and more obtuse and inflated frond. Fig. 1. Asperococcus Turneri. 2. Small section magnijinl, showing the spots of fructification, vertical view. 3. Fragment more hujhhj magnified, to shew the internal net-work. 4. One of the spots of fruit, viewed laterally. ;yerme-omitra Cabrer.e :— natural six. 3. Tart of a branch, showing ° fte barren and fertile apices. 3. View of the surface of the frond. 4. Trans- verse section of a branch. 5. Receptacle of fruit. 6. Transverse section of the same. 7. Vertieellate filaments, and spores from the same: — all i.uiijmfivd. f laic J I '. Ser. Rhodospermejs. Fam. Spharococcoidece. Plate XV. GRACILARIA MULTIPARTITA, /. A g . Gen. Char. Frond filiform or rarely flat, carnoso-cartilagmous, continuous, cellular; the central cells very large, empty or full of granular matter; those of the surface minute, forming densely packed, vertical fila- ments. Frur tification of two kinds, on distinct individuals ; 1, con- vex tubercles ( coccidia ), having a thick pericarp composed of radiating filaments, containing a mass of minute spores on a central placenta ; 2, tetraspores, zoned or tripartite, imbedded in the cells of the surface. Gracilaria (Grev.), — from gracilis, slender. Gracilaria multipartita; frond flat, tender, semi-transparent, brittle, dull purplish red, deeply cleft in an irregularly dichotomous or palmate manner; the branches linear-wedge-shaped, apices acute, tubercles conical, very prominent, scattered over the segments. Gracilaria multipartita, /. Ag. Alg. Medit. p. 151. Gracilaria polycarpa, J. Jg. I. c. p. 151. Plocaria multipartita, Endl. 3rd Sitppl. p. 51. Plocaria polycarpa, Endl. I. c. p. 51. Chondrus multipartitus, Grev. Syu. p. lvi. Harv. in Hook. Journ. Bot. vol. i. p. 155. Spilerococcus multipartitus, Ag. Sp. Alg. vol. i. p. 247. Ag. Syst. p. 212. Sph^rococcus polycarpus, Grev. Sc. Cryp. Fl, t. 352. Rhodomexia polycarpa, Grev. Alg. Brit. p. 87. Hook. Br. Fl. vol. ii. p. 289. Hare. Man. p. 61. Wyatt, Alg. Banm. no. 108. Fucus multipartitus, Clem. Hist. p. 311. FuctJS granatus, Turn. Hist. t. 215 (excl. syn. Lamx.). Fucus seruginosus, Turn. Hist. 1. 147. Hab. On rocks and stones in the sea, in muddy places, chiefly estuaries ; near low-water mark, and at a greater depth. Very rare. Annual. August and September. Shore under Tail's Hill, Plymouth, Miss Hill (1802); Mr. R. Sconce. Plymouth Sound, abundantly, Eev. W. S. Hare, Mr. J. W. RoJdoff, Dr. Coch. Whitsand Bay, Dr. Jacob. Dredged in Salcombe Bay, Mrs. Wyatt. Geogr. Distr. Shores of Europe from the south of England to Spain. East coast of North America, from New York to Florida. California. West Indies (Miss Di.r). Pemainbuco, Areschong. Eed Sea, Lord Falentia. Mauritius, Mrs. Telfair. Descr. Root, a thin spreading disk. Frond four to twelve inches long, Hat, cleft nearly to the base in an irregularly dichotomous manner; sometimes vaguely divided, or palmate ; sometimes having the lesser segments seeund, and often margined with horizontal lacinife. The breadth of the frond varies from half a fine to more than half an inch ; the thickness is com- monly nearly the tenth of an inch. When freshly gathered it is " thick, cartilaginous, tender, semitransparent, and very brittle "; but when dry, it becomes tough and shrinks considerably. The tubercles are large, corneal, depressed at the apex, very prominent and abundantly dispersed over the frond. They contain, under a thick pericarp composed of vertical, densely packed filaments, a roundish mass of minute spores spread upon a hemi- spherical central placenta. The tetraspores are scattered over the whole surface of the plant which produces them, and are mostly triangularly divided. Colour a dull purple, becoming greenish on exposure. I am indebted to M. Lenormaud for having pointed out to me the identity between the Bhodomenia pohjcarpa of Greville, and the older Fucus multipartitm of Clemente, which Greville includes in his genus Chonarus ; and also for a suite of beautiMly preserved specimens, showing the changes which this most variable plant assumes, according to the circumstances under which it grows ; and I have had the additional advantage of consulting, in the Herbarium of Mrs. Griffiths, an authentic spe- cimen of Fucus multipartitm, from Cadiz, which is in all respects similar to some of our British individuals. Prof. J. Agardh, while be transfers the Mod. pohjcarpa and Chondrm multipartita* of Greville to the reformed genus Gracilaria, retains both species. With respect to the Vacua aeruginosa* of Turner, which I had been in the habit of regarding as the typical state of G. multi- partita, and which I had hitherto looked upon as truly distinct from our British B. polycarpa-. a more carefid examination and a comparison of multitudes of specimens from very distant parts of the world, induce me now to regard this as merely a variety origi- nating probably from the plant's growing in rougher water, beyond the influence of the estuaries; and consequently acquiring a firmer texture, and narrower segments : the marginal processes are com- mon to all the varieties. A still more remarkable form of this species is Agardh's var. S. angudissimm, of which specimens have been kindly sent to me by Prof. J. W. Bailey, of New York, who obtained them at Providence, Rhode Island, where vast quan- tities of this variety grow on sandy bottoms. These specimens are quite as slender as Gracilaria confervoides, and nearly cylin- drical, excessively divided, and forming bushy tufts. But that the very narrow ones are mixed with others, which show a decided return to the common form of the species, one woidd never suspect them to belong to it ; yet some are covered with the characteristically abundant tubercles. Mr. Hore has found at Plymouth, as Mrs. Griffiths informs me, specimens almost equally narrow. Pig 1 Gracilaria multipartita:— natural me. 2. A portion, showing the pitted appearance of the surface :— slightly magnified. 3. Section ot frond and tubercle, to show the structure of both. -A. Spores from the tubercle. 5. Tetraspores. 6. Section of a thicker portion of the frond -.—all highly magnified. Scr. B,uodosperme.e. Kuin. Cerat Plate XVI. GRIFFITHSIA DEVONIENSIS, Harv.fy.sp.) Gen. Char. Frond rose-red, filamentous ; filaments jointed throughout, mostly dieliotomous ; ramuli single-tubed ; dissepiments hyaline. Frnc- tifa-ation of two kinds, on distinct individuals : 1, tetraspores affixed to whorled hwolucral ramuli ; 2, gelatinous receptacles {favellce), smToimded by an involucre, and containing a mass of minute angular spores. Griffithsia — so named by Agardh, in honour of Mrs. Griffiths of Torquay, the most distinguished of British Algologists. Griffithsia Deromensis ; filaments very slender, gelatinous, flaccid, dicho- tomous, the lower axils patent, the upper acute; articulations cylin- drical, 7-8 times as long as broad ; joints constricted ; involucres whorled round the joints of the branches. Hab. Muddy sea-shores, in deep water : rare. Plymouth, Rev. W. S. Ihre (July 1840). At Salcombe, Mrs. Wyatt (Sep. 1840). Geogr. Distji. South of England. Descr. Filaments 2-3 inches high, tufted, very slender, diehotomously divided, fastigiate, the lower axils very patent, the upper acute ; branches mostly naked, but sometimes throwing out short, root-like, lateral branchlets. Substance soft and gelatinous, closely adhering to paper, and having a gloss when dry. Articulations many times longer than broad, cylindrical, slightly incrassated at each end ; the joints constricted. Tetraspores affixed to the inner face of short involucrttl ramuli which are densely whorled round the main filaments, at the apex of an articulation, where they form roundish masses. Favellce unknown. Colour rose-red, soon discharged in fresh-water. This graceful little plant, which appears different from all the species of Griffithsia yet described, was discovered in the summer of 1S40, by the Rev. Mr. Hore, at Plymouth ; and, in the autumn of the same year, added to the flora of Devonshire by Mrs. Wyatt. I record this latter habitat in the specific name because it affords me an opportunity, of which I gladly avail myself, to connect the name of Mrs. Griffiths with that of the county whose shores she has so long and so successfully explored, where the best part of her life has been spent, and the natural history of which, in all its varied branches, her researches have so greatly advanced. G. Devoniensis obviously belongs to the section of the genus typified by G. corallina, from which species the smaller size, more E 2 slender filaments, and cylindrical articulations sufficiently distin- guish it. It agrees better in these respects with the rare G. barbata, but differs in its inflorescence, if I may venture to use that term to express the disposition of fruit. The genus Griffithda, proposed by Agardh, in 1824, has been universally adopted by botanists, and now includes nearly thirty species, scattered through the seas of all temperate climates, and reaching even to the troubled ocean of Cape Horn. One species is tropical ; several of great beauty are found in the Mediterra- nean ; and the shores of Australia, the Cape of Good Hope, and Western South America contribute others. All the species possess a common property, that of being exceedingly impatient of the contact of fresh water. To secure well-preserved specimens they should be brought home in salt water, and kept in it till they can be laid on paper. A short exposure to air is sufficient to decom- pose them, and fresh water causes the membrane of the cells to burst, and the colouring matter to be discharged with violence, as well described by Dr. Drummond in Loudon's Magazine of Natural History. The genus is nearly allied to Callithamnion, and still more nearly to Wrangelia, from which latter it is chiefly distinguished by having the tetraspores involucrated. Pip;. 1. Griffithsia Devoniensis : — natural size. 2. Upper portion of a filament. 3. Involucre. vK\ov, a leaf, aud (poptm, to bear : a proliferous frond. Phyllophora Brod'uei ; stem cylindrical, filiform, branched, the branches expanding into oblong, simple or forked, fiat, membranaceous frond- lets, which are proliferous from their extremity ; tubercles sessile on the tips of the segments. Phyllophora Brodiiei, /. Ag. Alg. Medit. p. 93. Endl. 3rd Swppl. p. 38. Coccotylus Brodiaei, Kiitz. P/tyc. Gen. p. 412. Choxdrus Brodiaei, Orev. Alg. Brit. p. 133. Hook. Brit. Fl. vol. ii. p. 303. Mack. Fl. Hib. part 3. p. 203. Han. Man. p. 78. Sph/erococcus Brodiaei, Ag. Sijn. p. 27. Lyngb. Hijd. Dan. p. 11. t. 3. Ag. Sp. Alg. vol. i. p. 239. ' Ag. Syst. p. 213. Grev. Fl. Edin. p. 295. Delesseria Brodiaei, Lamas. Ess. p. 37. Fucus Brodiaei, Turn. Hist. t. 72. E. Bot. t. 1966. Fl. Ban. t. 1-176. Var. /3. simplex ; stem short expanding into an oblong, simple or once forked, rose coloured frond ; sorus elliptical, composed of tetraspores. Choxdrus Brodiaei, /3. simplex, Grev. Alg. Brit. p. 133. Hook. Br. Ft. I. c. Harv. Man. 1. c. TJ'yatt, Alg. Brit. no. 121. Fucus membranifofius, var. roseus, Turn. t. 71. f. m. Hab. On rocks in the sea. Pare. Perennial? Winter and Spring. Eastern coast of Scotland, in several places. Lossiemouth, Mr. Brodie. Mouth of the Bann, Co. Derry, Mr. B. Moore. At Bangor, on Belfast Bay, Mr. W. Thompson. Yar. /3, Devonshire, Mrs. Griffith. Malahide, Mr.Mc'Calla. Geogr. Distr. Baltic Sea, Mertens. Denmark, Lyngbye. German Ocean. At- lantic coast of France, rare. Descr. Root a small disc ; in /3, a widely expanding disc. Frond 2-8 inches high ; the stem cylindrical, variable in length, simple or branched, the branches expanding into oblong, flat, forked or simple, wedge-shaped leaves, which vary in breadth from two to five lines, and in length from one to three inches. The segments are somewhat truncate, often proliferous from f2 the apex, the young shoot rising with a cylindrical stem, which soon expands into a frondlet resembling the primary one, and this in old specimens often gives birth to a second or third. Tubercles or nematJiecia very convex, dark red, sessile on the tips of the frond, composed of dichotomous, densely packed, moniliform filaments, radiating from a centre. — /3. is not quite two inches high, once or twice proliferous, of a fine rose-red colour, the frond- lets often bearing above the middle a broad, elliptical, dark-red, thickened spot, composed of tetraspores. " The study of natural history," remarks Mr. Turner in his history of the present species, " inclependantly of the advantages so nobly ascribed by Cicero to polite literature in general, that it nourishes our youth, delights our age, is an ornament in prospe- rity, and a comfort in adversity, may justly boast a still superior object, in leading, and, indeed, in forcing man to the admiration of the wisdom, and the goodness of his divine Creator, in the contemplation of the works of his Almighty hand. In addition to this it mixes itself also with the daily occurrences of social life, and gratifies the best feelings of our nature, by uniting in the bonds of friendship those whose pursuits were already the same ; while, by permitting the names of its votaries to be affixed to plants, it records their zeal in its service, and touches one of the most powerful springs of human action. Among those who emi- nently deserve to be thus mentioned, stands forward the name of James Brodie, Esq., of Brodie, in Scotland, a man at once zealous in the pursuit, and liberal in the patronage of universal science, and especially of the Botany of Britian." Mr. Brodie was par- ticularly attached to the study of the Alga?, among which he made many interesting discoveries, the present among the number, and during a long and active life, enjoyed the affectionate respect of a large circle of scientific friends ; the genus Brodicea is conse- crated to his memory. The specimen of Phyllopltora Brodieei, which I here represent was collected by Mr. Brodie, and given to me among many others by Dr. Walker Arnott, the present owner of the Brodisean Herbarium. Pig. 1. PhylLOPHCRA BliODIiEI, var. a. 2. Yjar. j3: — natural si :e. 3. Frond- let of var. 0, with sorus. 4. Tetraspores from the same. 5. Section of nemathecium. 6. Filaments from the same. 7. Spores (?) from the same. 8. Section of the frond, to show the internal structure : — all more or less magnified. Ser. Rhodosperme.£. Fam. Ceramiece. Plate XXI. SEIROSPORA GRIFFITHSIANA, Haw. Gen. Char. Frond rosy, filamentous; stem articulated, one-tubed, the articulations traversed by jointed filaments; brandies jointed, one- tubed. Fruit : oval tetraspores disposed in terminal, moniriform strings. Tavelke ?. Seirospora — from o-cipd, a chain, and o-nopos, a seed; chain- seed. Seirospora Grijfithsiatia. Callithamxion seirospermum, Griff, in Han. Man. p. 113. Callithamxiox versicolor, /3. seirospermum, Han. in Hook. Journ. Bot. vol. i. p. 302. Han. in Mack. Fl. Hib. part 3. p. 216. Wyatt. Jig. Duma. no. 19. Hab. On rocks and stones in the sea, in four to six fathoms water. Rare. Annual. Summer. At Torquay, Mrs. Griffiths. 8alcom.be, Mrs. Wyatt. Portaferry, Mr. W. Thompson. Arran, Rev. I). Lands- borough. Geogr. Distr. British Islands, rare. Sweden, Areschoug. Descr. Boot a small disc. Stems solitary or slightly tufted, 1-3 inches high, setaceous, generally undivided, more or less opake and veiny ; the veins, which are internal, articulated fibres, originating at the insertion of the branches, and traversing the stem in a downward, root-like direction. Branches tetrastichous or sub-distichous, numerous, loDg, simple, alternate, patent, issuing along the length of the stem from a short distance above the base to the apes, closely set ; the lowest longest, the upper gradually shorter ; so that the general outline of the frond is triangular ovate. The larger branches often bear a second set of similar branches. All are more or less furnished with sub-dichotomous, multifid, level-topped ramuli, with a narrow-obovate outline, jointed, the joints 2-4 times longer than broad, somewhat swollen upwards. The tetraspores are elliptical, triangularly divided, arranged in beaded, dichotomous strings at the tips of the branches ; that is to say, speaking morphologically, the articulations of the terminal ramuli are trans- formed into tetraspores. Colour a tine rosy red. Substance gelatinous, flaccid, and closely adhering to paper. This beautiful plant was discovered by Mrs. Griffiths in the Autumn of 1833, and by that acute observer was at once pro- nounced to be a new species. I was not so confident of its claims to this distinction, and first described it as a variety of Callithcimnion versicolor, chiefly remarkable for a curious modifi- cation of fruit. There is, indeed, a close resemblance to strong growing plants of C. versicolor, so close that we are driven to look to the fructification for marks of difference. Here, however, the characters are so broadly defined, that if we regard the fruit of our Seirospora as being normal, according to the view first taken by Mrs. Griffiths and latterly though with some hesitation and reluctance adopted by me, we shall be compelled to form a new genus for its reception. In Cattitl amnion the tetraspores are borne laterally along the ramuli ; here the ramuli themselves are converted at maturity into strings of tetraspores ; a tetraspore being formed within each of the articulations of the ramulus. This character is quite as strong, in a generic view, as that which separates any other genus of Ceramiea, and amply sufficient to distinguish the plant from Callithamnion. Additional strength has certainly been latterly given to the view taken by Mrs. Griffiths, by the plant having been found in three new and widely separated habitats, namely, in Ireland, in Scotland, and in Sweden. I trust, therefore, that the species is well established. The specimen here drawn is a remarkably fine one, which I owe to the kindness of Mrs. Wyatt who gathered it at Salcombe. Average specimens are not much more than half the size. Fig. 1. Seirospora Griffithsiana : — natural size. 2, Portion of a branch. 3. Portion of the main stem. 4. Ramulus with a cluster of tetraspores 5. Tetraspores removed : — all highly magnified. AJJJ Ser. Melanosperme.e. Fam. Fctocarpea. Plate XXII. ECTOCARPUS HINCKSLE, Han. Gen. Char. Filaments capillary, jointed, olive or brown, flaccid, single- tubed. Fruit, either spherical, elliptical, or lanceolate utricles, borne on the ramuli, or imbedded in their substance. EcxocAitPUS — from cktos, external, and Kapnos, fruit. Ectocarpus Hincksia ; tufted, dark olive ; filaments irregularly and dis- tantly branched ; branches flesuous, furnished with secund raniuli pectinated ou the upper side ; utricles conical, sessde, Lining the inner face of the ultimate ramuli. Ectocarpus Hincksiae, JTarv. Man. p. 40. Hab. Parasitical on Laminaria bulbosa. Annual. June. At Ballycastle, Miss Hincks. Torbay, Mrs. Griffiths; Mrs. Wyatt. Aberdeen, Dr. Dickie. Plymouth, Rev. W. S. Hore. Mounts Bay, Cornwall, abundant, Mr. Ralfs. Geogr. Distr. British Islands. Descr. Filaments 1-2 inches high, dark olive, somewhat rigid for the genus, (the substance very similar to that of E. littoral is), irregularly and rather distantly branched, not matted together. The branches are furnished in the upper part with secund spreading or somewhat recurved ramuli, which bear on their inner faces a second series of closely set, subulate ones ; the com- pound ramulus resembling a httle comb. Utricles conical, sessile, produced along the inner face of the ramuli, one rising from almost everv joint, giving to the ranmlus the appearance, under a lens of low power, of being serrated. My first knowledge of this species was from a solitary specimen gathered in 1840, by Miss Hincks, daughter of the venerable and respected Dr. Hincks, of Belfast. Though I had then seen but one specimen, yet so striking were its characters that I did not he- sitate to describe it forthwith as a new species ; and I had much pleasure in dedicating it to its discoverer, to whom I am indebted for many beautifully prepared and judiciously selected specimens of Algce, and from whose explorations of our northern shores much more novelty may be expected. Miss Hincks foimd her specimen on " one of the Laminariae," but neglected at the time to notice which. The uncertainty of habitat is, however, cleared up by Mr. Ralfs, who finds that in June, at Mounts Bay, Cornwall, the stems of L. hdhosa, are almost exclusively infested with this rare plant. I did not find this to be the case last summer at Valentia, where E. fasciculatus was the prevailing parasite, nor has any other observer found E. Hincksiee in similar abundance. Nevertheless it is, perhaps, not uncommon, but without a carefid inspection may be over- looked. A pocket lens is, however, amply sufficient to detect it, the comb-like, often scorpioid, ramuli affording an obvious charac- ter. When growing, as it sometimes does, mixed with E. silicu- losus, the brighter and more glossy, and softer threads of the lat- ter may be readily discriminated. I shall look forward with interest to its occurrence on the Continent. It ought to inhabit most of the Atlantic shores of Europe, but I cannot find any description that agrees with it. Fig. 1. Ectocarpus Hincksi.e : — natural .she. 1. A portion of a filament. 3. A pectinate ramulus. 4. Joints of the main filament. 5. Fertile ramulus. 6. The same, after the discharge of the sporaceous matter : — all more or less //iff kli/ magnified. ftaUlIIU Ser. Rhodosperme/e. Fam. Belesseriea. Plate XXIII. NITOPHYLLUM BONNEMAISONI, Grev. Gen. Char. Frond membranaceous, reticulated, rose-red, (rarely purplish), irregularly cleft, veinless, or furnished with irregular veins toward the base. Fructification, two-fold, on distinct plants : 1, spherical tuber- cles (coccidia) immersed in the frond, and containing a globular mass of angular spores ; 2, tetraspores grouped into definite sori or spots, variously scattered over the frond. Nitophyllum — corruptly formed from nitor, to shine, and (pvXKov, a leaf; shining-leaf. NrTOPHYLLTTM Bonnemaisoni; frond shortly stalked, fan-shaped or palmate, variously cleft into numerous wedge-shaped segments, furnished near the base with irregular, vanishing nerves ; spots of granules roundish, scattered over the surface of the frond. Nitophyllum Bonnemaisoni, Grev. Alq. Brit. p. 81. Hoolc.Br.M. vol. ii. p. 2S7. Han. in Mack. Ft. Sib. part 3. p. 193. Han. Man. p. 58. Delesseria Bonnemaisoni, Ag. Sp. Alg. vol. i. p. 186. Ag. Sgst. p. 252. arm. Sc. Crypt. Fl. t. 322. Aglaiophyllum Bonnemaisoni, Endl. 3rd. Suppl. p. 52. Hab. Growing on the stems of Laminaria digitata ; and on rocks and stones in 4 — 5 fathom water. Annual. Summer. Orkney, Rev. C. Clottston. Bute, Br. Greville. Lame, Br. Brummoncl. Youghal, Miss Ball. Torquay and Hfracombe, Mrs. Griffiths. Traniore, Mm Taylor. Miltown Malbay and Kilkee, W.E.H. Strangford Lough, W.Thompson, Esq. Jersey, Miss White. Geogr. Dist. Coast of Normandy, Bonnemmson. British Islands. Desc Root a small disc. Stem a quarter of an inch long, cylindrical, expanding into a fan-shaped, delicately membranaceous frond, 2-4 inches in length, and rather broader than its length, rarely quite veinless ; usually marked toward the base with more or less evident, vanishing nerves, which some- times extend considerably up the segments, and sometimes are nearly con- fined to the very base. The habit of the frond varies much in different in- dividuals, in some the lamina is very broad and not deeply cloven ; in others cleft nearly to the base in long ribbon-like segments. The division is pretty regularly dichotomous, but the margin in some specimens is proliferous, giving the frond a very compound aspect. Colour a fine rosy red, becoming brownish, especially toward the base, in drying. Reticulations (fig. 3, 5.) smaller than in N. versicolor. Tubercles small, not very prominent, scattered over the frond. Spots of tetraspores oblong or roundish, minute, but larger than those of N. Hillite, very abundantly scattered over the surface. It more or less perfectly adheres to paper in drying. The fan-like outline, scattered groups of tetraspores, and obscure basal veins distinguish the present species from other British NitoplujUa. The nearest in affinity is certainly N. versicolor, already figured in this work, from which the basal veins, and the proportionally smaller size of the cellules composing the mem- brane, together with some small differences, more easily seen than described, distinguish it. From N. Gmeluri, which it re- sembles in form, it is at once distinguished by the very different disposition of the tetraspores ; from N. Hittiee, by the thinner substance, smaller size, and less minute spots of tetraspores ; and from N. pundatum, by the different outline of the frond. The specimens here represented, which are of the average size of those that occur on the west of Ireland, where this species is constantly found growing on the stems of Laminaria digitata, are less luxuriant than those figured by Dr Grevdle. They are quite as large, however, as any Devonshire specimens I have seen. No doubt, at Lame, where all the Nltophylla luxuriate, so that the shore is pink with them, the present species reaches a much larger size. Pig. 1. Nitophyllum Bonnemaisoni : — with tetraspores. 2. A specimen pro- ducing tubercles ; — natural size. 3. Portion of the frond, with a sorus. 4. tetraspores from the same. 5. Portion of the frond, with a tubercle. 6. Spores : — all more or less highly magnified. A. Ser. Chloiuxsperme.k. Fau). Confemvc. Plate XXIV. CLADOPHORA REFRACTA, Kiitz. Gen. Char. Filaments green, jointed, attached, uniform, branched. Fruit, aggregated granules or zoospores, contained in the joints, having, at some period, a proper, ciliary motion. Cladophora — from /c\a8os, a branch, and o P ea, to bear ; a branching plant. Cladophora refracta ; filaments capillary, somewhat rigid, tufted bright o-reen very much branched ; secondary branches spreading on all sides, repeatedly' divided, thickly clothed with very much spreading or re- flexed, short branchlets, which are pectinated with ramuH on their upper' surface; articulations twice or thrice as long as broad. Cladophora refracta, Kiih.Phyc. Gen. p. 267. Conferva refracta, Roth. Cat. vol. ii. p. 193. Ag. Syst. p. 114. Han. Man. p. 137. Wyatt, Jiff. Damn, no 228. Hab In rocky pools, left by the tide, near low water mark. Annual. Summer. 'Dunlecky Castle, Kilkee, W. H. E. Ilfracombe, Mrs. Griffiths Mangans Bay, Cork, Miss Ball. Giants' Causeway, Mr. W Thompson Jersey, Miss Turner. Falmouth, Mm Warren. Mounts Bay, and Torbay, Mr. Eal/s. Howth and Balbnggan, Miss Gower. Geogr. Distr. Baltic Sea. Shores of the British Islands. Descr. Filaments densely tufted, 3-4 inches high,_ slender rather rigid; the main stems often woven or matted together m rope-like bundles, he secondary branches free, spreading on all sides and much divided ; the ultimate 'branchlets very patent or reflexed, frequently opposite, pectinated on their upper face. Very frequently a minute rainulus stands opposite to a pectinated branchlet, several of which Mow each other m a second manner along the stem. Colour a brilliant yellowish green, peculiarly glossv when the plant is growing, and partially preserved in drying. Sub- stance rather harsh for so slender a plant, very imperfectly adhering to paper. If our reference to Roth be correct, the present plant was dis- covered by M. Trentepohl on the shores of the duchy of Oldenburg, about the year 1799, and has been detected since that period on many of the coasts of northern Europe. Specimens communi- cated to me by M. Areschoug, of Gottenbmg, precisely agree with those from the British coasts. It was probably confounded by earlier British writers with C. albida, not having been recognized as British until I gathered it in the year 1833. So many habi- tats have since been recorded for it, that it may be regarded as a generally distributed form, if not species. It most nearly agrees in character with C. alblda, but the fila- ments are coarser, and far more rigid, standing oixt from each other when the tuft is removed from the water ; the colour is a brighter and fuller green ; the idtimate branches are shorter and more patent, often strongly reflexed, and the general habit is by no means spongy. It appears to prefer the clearest and purest water, growing on the bare rock or among corallines in deep cold pools left by the tide, near the extreme of low water mark. Where I have seen it, both at Kilkee and Dingle, it coidd only be reached at spring tides. Fig. 1. Cladophora refracta :— natural size. 2. Portion of a filament. 3, 4. Hamuli : — more or less highly magnified. PloittM) Ser. MelanospermevE. Fam. Bictyotea. Plate XXV. STRIARIA ATTENUATA, Greo. Ge.n". Chak. Root, a small, naked disc. Frond tubular, membranaceous, continuous, branched. Fructification; groups of naked, roundish spores, disposed in transverse lines. Striakia — from the spores being arranged in transverse stria or lines. Striaria attenuata ; branches and ramuli mostly opposite, tapering to each extremity. Striaria attenuata, Grev. Crypt. Fl. {Syn.) p. 44. Alg. Brit. p.55.t.9. Hook. Br. Fl. vol. ii. p. 279. Harv. in Mack. Fl. Hib. part 3. p. 176. Wyatt, Alg. Damn. no. 160. Meneg. Alg. Ital. et Balm. p. 157. /. Ag. Alg. Medit. p. 41. Bndl. 3rd Supjpl. p. 26. tttz. Phyc. Gen. p. 3S6. t. 31. f. 2. Harv. in Hook. Joitrn. Bot. vol. i. p. 298. McCalla, Alg. Hib. no. 18. Scytosiphon olivascens, Carm. MSS. Carmichaelia attenuata, Grev. Sc. Crypt, t. 288. Zonaria Naccariana, Ag. MSS. Nac. Fl. Fen. vol. vi. p. 94. Alg. Adr. p. 82. Zonaria lineolata, Ag. in Biar. Ratisb. 1827. Ag. Alg. Eur. t. 40. Stilophora crinita, Ag. Aufzald, p. 17. Nac. Fl. Fen. vol. vi. p. 94. Alg. Adr. p. 83. Solenia crinita, Ag. Syst. p. 186. Solenia attenuata, Ag. Syst. p. 187. Ulva attenuata, Nac. Fl. Fen. vol. vi. p. 72. Alg. Adr. p. 54. Dictyota lineolata, Greo. Syn. pi. xliii. Conferva crinita, Ruc/i.Fl. Fen. p. 269. Hab. Parasitical on the smaller Algae, generally growing beyond the tide range. Annual. Summer. Appin, Capt. Carmichael. Bute, Br. Greville. Belfast Lough, Br. Brummond. Strangford Lough, Mr. W. Thompson. Torbay, Mrs. Griffith; Miss Cutler. Rouudstone Bay, Mr. Mc'Calla.. Devonport, Mr. Ralfs; Rev. IF. S. Hore. Pen- zance and Lfracombe, Mr. Ralfs. Geogr. Distr. Shores of British Islands. Coast of Sweden, Aresclwug ! Mediterranean Sea. Desc. Root a small, scutate disc. Fronds tufted, 3-12 inches long, or more, from half a line to one or two lines in diameter, tubular, tapering to each extremity, furnished at short intervals with branches similar in form, but of rather less diameter than the main frond, which are again beset with smaller ramuli. Brandies and ramuli mostly opposite, sometimes in threes, rarely scattered, patent, all much constricted at their insertion, and produced at their apices into very fine, setaceous points. When in fructification, the branches, in all parts of the frond, are marked, at spaces of half a line asunder, with transverse rings or bands composed of clusters of roundish spores, lying exposed on the surface of the membrane, and slightly promi- nent, among which are occasionally seen a few short filaments, similar to those that accompany the spores in several other Bicti/otea. Substance of the frond delicately membranaceous, closely adhering to paper in drying. Colour a pale olive. Reticulations of the frond large, quadrate. As far as the British Flora is concerned, the merit of having discovered this plant belongs to the late talented and indefati- cable Captain Carmichael of Appin, who detected it upon the west coast of Scotland, in the year 1825 or 1826. In 1827 a figure of it appeared in Dr. Greville's ' Cryptoganiic Flora'; in 1831 it was discovered in Ireland, and in 1833 added to the Flora of Devonshire. But if the very numerous synonymes de- tailed above, and many of which I have transferred from the ex- cellent work of Meneghini, all belong, as there is little doubt, to our plant, it was first observed in the Mediterranean Sea, where it appears to be not very uncommon, in several places. Not a little remarkable, as connected with its Mediterranean habitat, is the fact that so far from its appearing to delight in warm latitudes, the specimens from Scotland and from the north of Ireland are in every respect stronger and more luxuriant than those found on the Devonshire coast. Other circumstances, exclusive of cli- mate, probably influence the growth of this, as of many other Alga?, very considerably. Of these the principal appear to be shelter, a quiet sea bottom, and a considerable deposit of alluvial matter. In such localities as Belfast and Strangford Loughs the largest specimens I have seen have been found. One of these, in the possession of Dr. Drummond, is considerably larger than that represented in our figure. A second species of this genus, S.fragilis, J. Ag. will probably be found on our shores. The specimens which I possess, so named by Prof. Agardh, are not in a sufficiently perfect state to enable me to form a decided opinion as to their specific character. I regret that our plate has been printed in too dark an ink, an error which was not perceived till the impressions had been struck off. Fig. 1. Striaria attenvata ; natural me. 2. Portion of a branch. 3. A portion of the membrane, with a sorus. 4. Spores from the sorus :— all more or less magnified. XXVI. Ser. Rhodospf-rme*. Earn. Belessenea . Plate XXVI. DELESSERIA RUSCIFOLIA, Lamour. Gen. Char. Frond rose-red, flat, membranaceous, with a percurrent mid- rib. Fructification of two kinds, on distinct individuals : 1, spherical tubercles (coccidia) immersed in the frond, and containing a globular mass of angular spores ; 2, tetragpores forming defined spots in the frond, or in leaf-like processes. Delesseria — in honour of Baron Benj. Belessert, a distinguished Botanist and Patron of Botany. Delesseria ruscifolia ; frond linear-oblong, obtuse, repeatedly proliferous from the mid-rib with leaflets of a similar form ; leaflets traversed by obbque, anastomosing, pellucid striae ; tubercles on the mid-ribs of the smaller leaflets ; tetraspores forming linear spots at each side of the mid-rib. Delesseria ruscifolia, Lamour. Ess. p. 124. Ag. Sp. Alg. vol. i. p. 175. Ag. Syst. p. 249. Grev. Alg. Brit. p. 76. Hook. Br. Fl. vol. ii. p. 286. Hare, iu Mack. Fl. Hib. part 3. p. 192. Harv. Man. p. 56. Endl. 3rd Suppl. p. 53. Mc'Calla, Alg. Hib. no. 12. YYormskioldia ruscifolia, Spreng. Sgst. Feg. vol. iv. p. 331. Hypoglossum ruscifolium, Kutz.Phyc. Gen. p. 444. Fucus ruscifolins, Turn, in Linn. Trans, vol.vi. p. 127. t. S. f. 1. Syn.Fuc. p. 11. Hist. 1. 15. 8m. Mug. Bot. 1. 1395 . Hab. Generally growing on rocks, near low water mark ; sometimes para- sitical on "other Algae. Annual. Spring, Summer, and Autumn. Not uncommon on the shores of England and Ireland. Geogr. Distr. Atlantic shores of Europe. Cape of Good Hope, W. H. H. Van Dieman's Land, Mr. Giinn. Desc. Root a small disc. Fronds several from the same base, consisting of a primary leaf 2-4 inches in length, about 4 lines in breadth, linear-oblong, obtuse" undivided, entire at the margin, but often somewhat wavy and curled, with a' strong mid-rib, producing numerous other leaves in a proliferous maimer, all of similar shape to the primary ; and these again producing a third and fourth set, until there results a much branched frond. All the leaflets spring regularly from the mid-ribs of those first formed. The cel- lules composing the membrane of the leaves are very minute, angular and closely packed ; but the substance is traversed with brandling and anasto- mosing, pellucid, jointed stria; or veinlets, composed of a single string of elongated cellules, and running in an oblique direction, from the mid-rib to the margin. Tubercles seated on the mid-ribs, generally toward the apices of the younger leaves. Sori linear, elongated, forming interrupted hnes at each side oHhe mid-rib. Colour, a transparent blood-red. Substance more rigid than in J). Hypoglossum. Delesseria ruscifolia was discovered on the Yarmouth shore by Mr. Dawson Turner, who " after having observed its characters for many successive years " published an excellent account of it in the ' Linnaean Transactions ' in 1801. It has always since been regarded as a distinct species, though confessedly very closely allied to D. Hypoc/lossum, and is now known to occur in the southern Hemisphere, as well as along several of the European shores. Specimens which I have gathered at the Cape of Good Hope appear identical with British ones. Mr. Tmner, in the memoir alluded to, and in his subsequent works, has entered very fully into the points of difference between the present species and its nearest ally, D. Hijpoglossmii, figured in our first number. A comparison of the figures will make these differences obvious. In D. Mypoglossum the leaflets are lanceo- late, tapering to each end, and generally, but not constantly, acute ; in D. ruscifolia they are linear-oblong, much broader in proportion to their length, and always very blunt. But besides differences of form, which are not always constant, the cellules composing the membrane in the present species are much smaller, the substance denser and thicker, and the colour more intense than in D. Hypoglossvm ; while the confervoid stria? which traverse the leaves, and are readily seen in D. ruscifolia, are either very obscure or do not exist in D. Hgpoghssum. Fig. 1. Delesseria ruscifolia ; with tetraspores. 2. The same, producing; tubercles : — natural size. 3. a leaflet, with sori. -i. Portion of the same, showing the pellucid stria?. 5. Tetraspores. 6. Leaflets with tubercles. 7. Portion of the same. 8. Globule of spores, removed from tubercle. 9. Spores separated : — all wore or less magnified. Ser. Rhodosperme.e. Fam. Ceramiea. Plate XXVII. WRANGELIA MULTIFIDA, J.Ag. Gen. Chaji. Frond purplish or rose-red, filamentous, jointed ; filaments single-tubed. Fructification of two kinds, ou distinct individuals : 1, tetraspores affixed to the inner face of the ramuli (not confined to involucres) ; 2, gelatinous receptacles {favella) terminating the branches, surrounded by an involucre, and consisting of several clus- ters of pear-shaped spores, compacted together. Wrangelia (Ag.) — in honour of Baron von Wrangel, a Swedish naturalist. Wrangelia multifida; stems setaceous, pinnate or bipinnate, articulated, each joint bearing a pair of opposite, slender, pinnato-multifid, in- curved ramuli, or whorled with numerous sub-dichotomous ramuli ; joints of the stem many times longer than broad. Wrangelia multifida, /. Ag. Alg. Medit. p. 79. Endl. 3rd Suppl. p. 35. Griffithsia multifida, Ag. Sgst. Alg. p. 143. Ag. Sj>. Alg. vol. ii. p. 133. Harv. in Hook. Br. Fl. vol. ii. p. 338. Harv. in Mack. Fl. Rib. vol. iii. p. 212. Harv. Man. p. 102. Wyatt. Alg. Dawn. No. 43. McCalla, Alg.Hio.No.l. Callithamnion multifidum, Kiitz. Phyc. Gen. p. 373. Ceramium verticillatum, Bucluz. sec. Ag. Ceramidm Casuarinae, B.C. Fl. Gall. Syn.j). 8. Conferva multifida, Hudson Fl. Ang. 596. Sm. E. Bot. 1. 1816. Billw. Conf. Syn. p. 75. Var. /3, pilifera ; ramuli very long, simple and hair-like. Griffithsia multifida /3. pilifera. Ag. I. c. Harv. I. c. Hab. On the perpendicular sides of deep marine pools near low-water mark, under the shade of other Algae. Frequent on the southern shores of England ; and west of Ireland. Belfast Bay, Mr. Thompson. Jersey, Miss White, Miss Turner. Rare in Scotland ? Saltcoats (floating), Miss Margaret Landsborough. Geogr. Distr. Atlantic coasts of Europe. Rare in the Mediterranean sea. Descr. Root accompanied by irregularly branching fibres. Filaments 4-8 inches high, as thick as hogs' bristles, generally undivided, but furnished throughout then length with lateral, opposite or alternate spreading, disti- chous or spirally quadrifarious, simple branches similar to the stem ; and like it bearing a second or even a thud series, which gradually become more and more slender. Stem and branches jointed, the articulations very variable in length in different specimens, 5-10 times longer than broad, single tubed, with a very wide hyaline border, each bearing at a short distance below the joint either a pah of slender, opposite pinnato-multifid ramuli (which seems to be the normal state of young individuals), or, as shown in our figure, numerous whorled, multifid incurved ramuli. The articulations of the ramuh are much shorter in proportion than those of the branches, being usually not more than twice or thrice as long as broad ; the apices are obtuse. In \ ar. the ramuli are sometimes simple, and naked, half an inch long or more; sometimes (fig. 3) pinnated with opposite, simple ramelli. OoUmr a fine, transparent, rose-red, perishing quickly in the air or in fresh water. Tetraspores minute, roundish with wide borders, sessile on the lower part of the ramuli. Favella borne on short branches, surrounded by an invo- lucre of multifid ramuli, berry-like, consisting of numerous distinct clusters of large pear-shaped spores, arranged in globose radiating tufts, densely compacted together. Substance at first crisp, soon becoming flaccid, and closely adhering to paper in drying. The description given by Hudson of his Conferva mulUfida, though brief, is so characteristic of the present species that I cannot help agreeing in opinion with Smith, that this is really the plant he intended, although Mr. Dillwyn, who holds a contrary opinion, informs us that an authentic specimen of Hudson's plant, communicated by Dr. Goodenough to Mr. Dawson Turner, proved to be Griffithsia equisetifolia. Hudson describes bis plant as " subgelatinous, much branched, with opposite, long branches ; opposite multifid, short, slender ramidi, remote and as if whorled " characters which agree well with Wrangelia multi- fida, whose ramuli are, I believe, always opposite and not whorled in the young plant ; they are remote ; and the branches are very frequently opposite. None of these characters coincide with G. equisetifolia. The genus Wrangelia, to which, following the recent views of the younger Agardh, I remove this plant, was founded by Bishop Agardh on a Mediterranean species, which agrees in its fructifi- cation with our IF. multifield, but which has an inarticulate, or rather an opake, internally jointed stem. The structure of the favella, and the disposition of the tetraspores are different from what occur in Griffithsia, and the branching of the frond is more pinnate than chchotomous. Some fine species of Wrangelia are found in Tasmania and New Holland. //" mulUfida, originally discovered on the south coast of Eng- land, seems to find its greatest perfection and beauty on the west coast of Ireland. Some of the Irish specimens would easily cover a quarto page. Pig. 1. Wrangelia miltifida : — natural size, 2. Portion of a branch. 3. The same, var. (3. 1. Hamulus with tetraspores. 5. Tetraspores. 6. Portion of a branch, with a favella. 7. Clusters of spores from the favella. \ivm Ser. Melanosperme/e. ■ Faml CAdrdariea ? Plate XXVIII. {A). ELACHISTEA ATTENUATA, iiarv. (s P . nov.) Gen. Char. Parasites composed of simple, vertical, or radiating, jointed filaments, issuing from beneath the surface-cellules of other Algae ; the lower part of the filaments hyaline and compacted together into a tubercle, the upper-half coloured (olive), free. Spores oblong, mostly stalked, affixed to the bases of the free portion of the filaments, or to the tubercular base. Elachistea {Duty) — seemingly from ckaxun-a, the least. Elachistea attenuata; tufts very minute, globose; filaments fusiform, much attenuated toward both ends, the basal joints 3-4 times, the middle once and a half, the apical about as long as broad ; spores linear-obovate, subsessile at the base of the filaments. Hab. Parasitical on the fruiting branches of Cystoseira ericoides. Annual. Summer and Autumn. At Elberry Cove, Torbay, Sep. 1844, Mrs. Griffith and W.H.H. Geogb. Distr. South of England. Descr. Tufts half a fine to nearly a line in diameter, spherical, originating in a minute tubercle, which extends its roots (or bases of its filaments) into the substance of the Cystoseira. MUments from a quarter to nearly half a line in length, thickened in the middle, tapering greatly to either end, obtuse, jointed. Lower articulations nearly colourless, slender, cylindrical, 3-4 times longer than broader; middle articulations sub-elliptical, con- tracted at the dissepiments, once and half as long as broad, containing a bag of bright olive granular endochrome ; upper articulations gradually shorter upwards, and gradually mouiliform towards the apex. Spores abundantly produced at the base of the filaments, narrow obovate, dark olive, with a wide limbus. In a delightful excursion, made in the autumn of 1844, in company with my valued friend Mrs. Griffiths, to visit the habi- tat of Gigartina Teedii at Elberry Cove, we observed that most of the fronds of Cystoseira ericoides, which grows in great luxu- riance on an exposed rock in the cove, were infested with the minute parasite here represented. The size and shape of the filaments readily distinguish it from any of the British Elachistea ; but in these characters it agrees with E. rivdaria, Suhr., from which it is chiefly distinguished by the globose form of the tuft. E. rivdarics, which also inhabits Cystoseira, and will probably be detected in this country, is described as being effused, in the manner of E. velutina. A. Fig. 1. Branchlet of Cystoseira ericoides infested with Elachistea attenuate : natural size. 2, Fragment of the same, slightly magnified. 3. Portion of the Elaehistea. 4. Tubercular base of the same, in its position. 5. A filament and spore : — all magnified. Plate XXVIII. (B). ELACHISTEA VELUTINA, Fries. Elachistea velutina ; spreading in thin, indefinite, velvetty patches ; fila- ments very minute, equal in diameter throughout, dissepiments slightly contracted ; joints once, to one and a half times as long as broad ; spores elliptical, pedicellate, affixed to the lower part of the filaments. Elachistea velutina, Fries, Flor. Scan. 317. Aresch. in Linnaa, vol. xvi. p. 235. t. 8. f. 9. Mykionema velutinum, Endl. 3rd Suppl. p. 23. Sphacelaria? velutina, Grrev. Crypt. Fl. t. 350. Harv. in Hook. Br. Fl. vol. ii. p. 325. Harv. in Mack. Fl. Hib. part 3. p. 181. Harv. Man. p. 39. Hab. Parasitical on Himanthalia lorea, frequent. On Focus serratus, Br. Grevitte. Shores of the British Islands. Geogr. Distr. Atlantic coasts of Europe ; probably common. Descr. Forming dark olive, velvetty patches of indefinite extent on the surface of the fuci affected, rooting in their substance. Filaments about a line in height, linear, obtuse, coloured, except at the very base, simple, or occa- sionally forked at a joint or two above the base. Articulations once, or twice as long as broad, slightly contracted at the dissepiments. Spores elliptical or oblong, or somewhat obovate, dark obve, with a wide limbos, supported on slender pedicels, which are evidently contracted filaments. Elachistea velutina was first observed by Dr. Greville who published an excellent figure of it in the sixth volume of his ' Cryptogamic Flora'. It occtu-s commonly on the long strap- shaped receptacles of Himanthalia lorea ; but I have not seen it on Emus serratus. Mr. Ralfs, who finds it abundantly on the Himanthalia, remarks that it very frequently accompanies E. scutulata, and often so closely resembles that species that it becomes difficult to distinguish them, except by the form of the spores. Usually, however, E. scutulata is readily known by occurring in raised, oval, shield-like patches. B. Fig. 1, Fragment of Himanthalia lorea infested with Elachistea velutina : — natural six. 2. Lateral sectional view of a portion of the Machistea, in situ. 3. Portion of the same. 4. Filaments in fruit, detached : — more or less magnified. t« Ser. Rhodospermejs. Fam. Ceramiece. Plate XXIX. MICROCLADIA GLANDULOSA, Grev. Gen. Char. Frond filiform, compressed, distichously branched, traversed by a wide, articulated tube, surrounded, by numerous, large, coloured, angular, radiating cells ; external coat formed of minute reticulated cellules. Fructification of two kinds, on distinct individuals : 1, tetra- spores imm ersed in the ramuli ; 2, sessile, roundish receptacles (fa- vellce), having a pellucid limbus, containing numerous minute angular spores, and surrounded by several, short, simple, involucral ramuli. Microcladia ( Grev.) — from iiupos, small, and xAdSor, a branch. Microcladia glandulosa, Grev. Microcladia glandulosa, Grev. Alg. Brit. p. 99. 1. 13. Hook. Br. Fl. vol. ii. p. 293. Harv. Man. p. 65. Wyatt, Alg. Danm. n. 68. Kiltz. Phyc. Gen. p. 382. Endl. 3rd Suppl. p. 36. Delesseria glandulosa, Ag. Spec. Alg. vol. 1. p. 182. Ag. Syst. p. 251. Jones et Kingst. Fl. Devon, part 2. p. 66. Fccus glandulosus, Soland. MS. Turn. Hist. t. 38. E. Bot. t. 2135. Hab. Growing on rocks in the sea, or on Algae, or Sponges, either near extreme low-water mark, or at a greater depth. Very rare. Annual. Summer. Budleigh Salterton, and Torquay, Mrs. Griffith. Falmouth Miss Warren. Teignmouth, Mr. Rolfs. Geogr. Distr. Southern shores of England. Atlantic shores of France and Spam. Marseilles, Kiitzing. Kamtschatka, Agardh. Descr. Roots fibrous, brandling. Fronds tufted, one to four inches high, about a quarter of a line in width, compressed, much branched from the base in an alternate or irregularly dichotomous manner, forming roundish, fastigiate tufts. Branches distichous, angularly zig-zag, irregularly divided, of nearly equal breadth throughout, the axils very patent, more or less furnished witli short, forked or dichotomous ramilli. Ramuli 2-3 lines long, once, twice, or repeatedly forked, with rounded axils, and subulate or bifid apices, the points in the latter case hooked inwards. When viewed with a pocket lens of moderate power the frond appears inarticulate, but marked with large reticulations, the internal cells being seen through the semi-transparent cellules of the surface. Under a lens of greater power this appearance vanishes in a great degree, and the frond seems to be closely cellular. A transverse section (fig. 8) exhibits a wide, empty centre surrounded by several large cells filled with granular endochroine, and bounded externally by the numerous minute, much compressed cellules of the surface. A longitudinal section (fig. 7) shows us that the central tube is divided, at regular intervals, into a series of loculi or joints, sepa- rated from each other by thin, transparent diaphragms. Colour a fine blood or rose-red, darker towards the base, and acquiring a brownish shade in drying. Substance cartaligineo-membranaceous, adhering, but not closely, to paper. Tetraspores sometimes cruciate, but generally triangularly divided, immersed in the ramuli, near their apices, and generally disposed in longi- tudinal series on the outer edge of the branchlet. Favella sessile on the outer margin of the ramuli, subglobose, or irregularly shaped, occasionally lobed, containing very numerous angular spores, and clasped by two or three short, involucral ramuli. We are informed by Mr. Turner, in his ' Historia Fucoruni', that a specimen of this beautiful plant, of British origin, but uncertain locality, had long been preserved in the Banksian Herbarium under the MS. name Fucus glanduloms, but remained unpublished until Mrs. Griffiths, in September, 1803, fortunately discovered it again upon the Devonshire coast, and enabled him to figure and describe it for the first time. Since that period it has been found, as far as I am aware, in but two other British stations, and in neither of them of such large size as in Torbay. To Miss Warren of Flushing I am indebted for a great number of specimens, and to Mrs. Griffiths for the line specimen here represented, and others in both kinds of fruit. I believe no one in Britain but Mrs. Griffiths has yet found Favella. On the continent, Microcladia glandulosa is decidedly rare, though found along the shores of France and Spain. Professor J. Agardh omits it in his 'Alga? Maris Mediterranei', but Kutzing has received it from Marseilles. Bishop Agardh mentions specimens from Kamtschatka, which, though somewhat different from the European plant, he considers to belong to the same species. This, if correct, is an interesting fact in the distribution of so rare a plant. As a genus, Microcladia is very closely indeed allied to Cera- miinn, with which it agrees in habit, and merely differs in some minor points of structure. Some specimens of Car. rubrum nearly resemble it, but the absence of external joints in the Microcladia, is a character sufficiently obvious to distinguish it from the Cera- mi urn. Microcladia glandulosa is often found tangled with other Algce, upon which it grows ; and sometimes, as Mrs. Griffiths observes, creeps over them in the mannei A of &opea, to bear; a branching plant. Cladophora Brownii; filaments forming dense, cushion-like tufts, erect, rigid, flexuous, elastic, slightly branched ; branches few, long, sub- simple, secund ; axils acute ; articulations four or five times longer than broad, the lower ones thickened upwards, the upper cylindrical. Cladophora glomerata, y. Brownii, Hass. Brit. Fr. Wat. Alg. p. 213. Conferva Brownii, Dittio. Suppl. t. B. Ag. Syst. Alg. p. 105. San. in Hook. Br. Ft. 2. p. 355. Han. in Mack. Ft. Sib. part 3. p. 228. Harv.Man. p. 13-i. Wyatt, Alg. Banm. N. 225. E. Bot. Suppl. t. 2879. Conferva pidvinata, R. Br. MSS. Hab. In maritime situations exposed to the alternate influence of salt and fresh water ; rare. Perennial. On wet rocks in a cave near Dimrea, R. Brown, Esq. On rocks at the entrance of a small cave beyond Black Castle, Wicklow (1833), W.H.H. Cornwall Coast, Mr. Ralfs. Geogr. Distr. Ireland. Cornwall. Descr. Tufts very dense, cushion-like, spreading over the rocks in patches of indefinite extent, one to several inches in breadth, from half an inch to nearly an inch in thickness in the middle, gradually thinner towards the edges, of a black-green colour when growing, but exhibiting, on having the water expressed, and being held between the eye and the light, a beautiful clear, yellow-green tint. Filaments so matted together that it is difficult to separate a single thread, very rigid, erect, but apparently originating in a mass of creeping, branched, densely matted fibres, which form the base of the tufts, flexuous, irregularly branched ; the branches long, simple, secund or subdichotomous. Articulations tolerably uniform in length, the lower ones clavate, the upper cylindrical ; joints contracted. Endoehronie dense. Perhaps I transgress the true limits of a work on marine Algae by figuring in it a plant which belongs as much to the land as to the sea, and which is only occasionally wet with sea-water. I have two reasons for doing so. First, because the upper figure in the ' Supplement to English Botany', which was obviously made from dried specimens by an artist who had never seen the living plant, is so imlike the living C. Brownii that it is quite useless as a representation of its natural habit ; secondly, because Mr. Hassall, in his recent work, considers C.Brownii to be merely a " condition of C. glomerata," arising "from the subimmersed habitat in which it grows." This opinion I cannot but regard as being too hasty, especially in an author who had never seen this remarkable plant growing. It is a mere assumption, for there is no evidence to show any passage from the one form into the other ; and the forms themselves are so broadly distin- guished that the most casual observer coidd not confound them. The habit of Cladophora Brownii is, as I have long since said, completely that of Vaucheria ferrestris ; a habit adnhrably ex- pressed in Mr. Brown's MS. name " pidvinata" . Such is very different from the sprayey branching of C. glomerata ; and if this character be regarded as valueless, we must be prepared to unite a host of other species with C. glomerata. But, setting aside habit, the rigid and tough substance of C. Brownii distin- guishes it, even in fragments, from every form of C. glomerata that I have seen. The " Prince of Botanists", who first detected and described it, and whose name it bears, may be allowed to be good authority in this matter. He examined the plant in a recent state ; so have I done ; and so, more lately, has Mr. Ralfs ; and we are agreed in pronouncing it a perfectly distinct species, at least as well characterized as any other specific form in the genus Cladophora, and better characterized than several reputed species. I hope the figure now given, and which is a faithful representation of the growing plant, will show that we have some grounds for our opinion. Cladophora Broionii appears to be peculiar to the British Islands, and, so far as I know, has only been found in the stations above given. At Wicklow, I observed it first in 1833 ; and in 1842, when I next visited the station, the plant was still to be found, though not in so luxuriant a state, probably from some failure in the supply of moisture. Fi°\ 1. Cladophora Brownii : — naiuralske. 2. 3. Filaments removed. 4. Por- tion of a tilament : — all more or less magnified. I XXI Ser. MELANosPERM&fi. Fam. Chordariea, Plate XXXI. MESOGLOIA VERMICULARIS, Ag. Gen. Char. Frond filiform, much branched, gelatinous. Axis composed of loosely packed, longitudinal, interlaced filaments, invested with gelatine ; the periphery of radiating, dichotomous filaments, whose apices produce clusters of club-shaped, moniliform fibres. Fructifica- tion, obovate spores, seated among the apical fibres. — Mesogloia {Ag.), from fte'o-or, the middle; and yXoios, viscid; in allusion to the gela- tinous axis. Mesogloia vermicularis; frond unequally distended, clumsy; branches irregularly pinnate, thick, worm-like, lineari-fusiform ; ramuli copious, long, flexuous, resembling the main branches. Mesogloia vermicularis, Ag. Syn. p. 126. Lyngb. Hyd. p. 190. t. 65. Ag. Sgst. p. 51. Harv. in Hook. Br. Fl. vol. ii. p. 387. Wyatt. Alg. Damn. no. 100. Kiltz. Phyc. Gen. p. 332. t. 27. f. 1. Menegh. Alg. Ital.et Balm. p. 279. Endl. 3rd Suppl. p. 23. Trichocladia vermicularis, Harv. in Mac. Fl. Hid. part 3. p. 186. Helminthocladia vermicularis, Harv. Gen. S. A. PL p. 397. Harv. Man. p. 45. Eivularia vermiculata, E.Bot. t. 1818. Ch;etophoka vermiculata, Hook. Fl. Scot, part 2. p. 75. Hab. On rocks and stones in the sea, about half-tide level. Annual. Summer. Common. Geogr. Distr. Atlantic shores of Europe. Mediterranean sea. Descr. Root small, discoid. Fronds tufted, 1-2 feet high, gelatinous, flaccid, but elastic, with a leading stem, which is either simple, or but slightly divided, somewhat flexuous, unequally distended and constricted at intervals, tapering to the base and apex, and beset throughout its length with very numerous, close, lateral branches. Branches similar in form to the stem, of various length, patent, or horizontal, more or less clearly pinnate, or furnished with alternate subdistichous or quadrifarious lesser branches, mixed with short tooth-like ramidi. Stem and main branches clumsy, from two to five fines or more in diameter, more coriaceous than others of the genus. Ultimate branches simple or forked, tapering to an obtuse point ; all the axils rounded. Filaments of the axis loosely interwoven ; their joints pear-shaped or cylindrical : — those of the periphery dichotomous, with globular joints ; ultimate fibres about live in a cluster, their joints gradually larger from the base upwards, containing granular matter. Spores e'liptical-obovate, sessile. Colour muddy olive, yellowish, or brown. This species, the best known and earliest described of the genus, as now restricted, appears to have been first noticed by i Dr. Drummond, who discovered it cast on shore at Larne, in August, 1806 ;— unless, as Dr. Arnott supposes, it be the JJlva rubens of Hudson, a syoonyme which I think better referable to Dudresn a ia diva rica fa . It is common on many parts of the coasts of England, Scot- land, and Ireland, and is found in the Isle of Jersey by Miss White ; but appears to be, in some districts, less common than 31. virescens. This, Mr. Ralfs remarks, is the case about Pen- zance, in Cornwall, and on the Welsh Coast. It is frequent in Torbay, and in other localities of the south of England ; and very abundant on the west and south-west coasts of Ireland. In the north-east of Ireland, where it was first noticed, Mr. Thomp- son finds it in profusion, and has observed, among heaps of sea- weed cast on shore " the partiality of the Idotea astrum, Leach, for the gelatinous Mesoghia vermicularis, plants of which it had very much eaten, leaving the other Alga?, of which there were many species in the heap quite untouched." I have given the Mediterranean station on the authority of Professor Meneghini, who has received it from Venice and from Trieste. It is omitted by Agardh in his Algae Mediterraneae. 31. vermicularis may be considered the type of the genus Mesoghia, as now defined by J. Agardh, consisting of that por- tion of the older genus to which I formerly applied the name of Trichocladia, subsequently changed into Helminthocladia. When I proposed 31. multifida of Agardh, as the type of the restricted genus Mesoghia, I was not aware that that species is identical in structure with Nemaleon of Tozzetti. To Nemaleon, M. mul- tifida is therefore now referred ; 31. Hudsoni (of British authors) and 31. coccinea to Dudresnaia ; and 31. moniliformis, Griff, to Crouania. Respecting the proper place of 31. purpurea, Harv. I am at present doubtful. Fig. 1. Mesogloia vermicularis, (small specimen): — natural she. 2. Por- tion of the filaments, axial and peripherieal, of which the frond is composed. 3. Apex, with its spore, and cluster of ultimate fibres : — Magnified. ^ m ■ ^m •A Ser. R,H0D0SPERMEiE. Pam. Sphcerococcoideai. Plate XXXII. RHODYMENIA BIFIDA, Grev. Gen. Char,. Frond flat, membranaceous, or subcoriaceous, ribless, veinless, cellular; central cells of small size; those of the surface minute. Fructification of two kinds, on distinct individuals ; 1, convex tuber- cles (coccidia) having a thick, cellular pericarp, and containing a mass of minute spores on a central placenta ; 2, tetraspores imbedded in the cells of the surface, scattered, or forming cloudy patches. Rhodymenia* (Grev.) — from poSeos, red, and v/ify, a membrane. Rhodymenia bifida ; frond thin and transparent, rose-red, dichotomously divided from the base ; segments linear, or ciuieate ; apices obtuse ; ■ tubercles mostly marginal, sessile ; tetraspores transversely zoned. Rhodomenia bifida, Grev. Jig. Brit. p. 85. Hook. Br. II. vol. ii. p. 289. Wyatt. Alg. Damn, no. 66. Harv. in Mack. Fl. Eib. part 3. p. 194. Earv. Man. p. 60. Fndl. 3rd Suppl. p. 51. Delesseria bifida, Lanwur.Fss. p. 37. Sph.erococcus bifidus, Ag. Sp. Jig. vol. i. p. 299. Syst. p. 231. Kiltz. Fhyc. Gen. p. 410. Fucus bifidus, Goodw. et Woodw. Lin. Trans, vol. iii. p. 159. 1. 17. f- 1- Sm. E.Bot.t.lli. Turn. Syn. p. 165: Turn. EM. 1. 154. Var. ft ciliata; frond somewhat thicker than usual, opake, brownish red, narrow, much divided; the margins fringed with leafy cilia. Fucus bifidus, /3. ciliatus, Turn. Syn. p. 165. EM. I. c. Var. y, incrassata ; frond thicker than usual, shrinking and changing to brownish red in drying, broad; segments cuneate, proliferous or ciliate at the margin. Hab. On rocks in the sea, beyond the influence of the tide, and on Adgfe. Annual. Summer. Frequent on the southern shores of England ; and along the west, and south, and eastern coasts of Ireland. Yar- mouth, Mr. Wigg. Tynemouth, Mr. Winch. Belfast Bay, Mr. Tem- pleton. Jersey, Miss White. Ardrossan, Saltcoats, and Kilbride, Rev. 1). Landsborough. Var. y, Belfast Bay, Mr. W. Thompson. Carrickfergus, Mr. Me' Calla. Geogr. Distr. Atlantic shores of Europe. Mediterranean sea. Descr. Root discoid, accompanied by fibres. Fronds 1-2 or 4 inches high, growing in globose tufts, veinless, thin, delicately membranaceous, dicho- tomous with more or less regularity, usually much divided; segments * Spelled Rhodomenia by Dr. Greville ; altered to Rhodymenia by M. Montagne, i being move in conformity with the Greek. linear, or slightly widened upwards ; in common varieties (tig. 2) from two to four lines wide, sometimes much narrower or much wider ; the axils rounded ; the apices obtuse, commonly truncate or subemarginate, some- times rounded, and occasionally slightly tapered. The margin is either entire and plane, or fringed with minute processes, which sometimes lengthen into proliferous foliations. Tubercles globose, generally abundant, and ses- sile along the margin of the segments; rarely scattered over the disc. Tetraspores forming cloud-like spots in the upper segments, oblong, divided by three transverse, zone-like fines. Colour in Var. a, a clear, transparent rose-red. Var. /3. is very much narrower, and more intricately and irregu- larly divided, of a darker, often very dark colour, opake, and thick, and forms entangled tufts. Var. y. is from half an inch to an inch in breadth, but little divided, cartilagineo-membranaceous, transparent, red when fresh, but becoming brownish, and not adhering to paper in drying; it produces marginal tubercles in abundance. Several other varieties are mentioned by Turner. „™™» Our plate represents three forms of this most variable plant, between the broadest and narrowest of which, innumerable states occur ; some of which, like our central figure, which may be re- garded as the normal state, are of a delicate rosy colour, trans- parent and membranaceous ; while others are more or less in- crassated, and, especially when dry, of a brownish red. The specimen represented at fig. 1. was gathered by Mr. Moore on the coast of Antrim, and Miss Hyndman has found, at Bun- doran, specimens of equal, or even greater luxuriance. Bhodymenia bifida differs from others of the genus, not merely in being more membranaceous, but in its fructification. The tetraspores, represented at fig. 9, are in it divided by transverse zones, like those of Plocamium, of Catenella, and of some other Alga? ; while in Bliodymenia proper they are of the more common tri-partite kind. This character, in the present genus-making age, is perhaps of sufficient importance to justify the removal of B. bifida to a new genus ; but I am not prepared to say how many, or whether any, others of the Bhodymenim have similar tetraspores. Should future observations confirm my suggestions, the new genus may be called Wiggliia, in memory of Mr. Lilly Wigg " the instructor " in marine botany of Dawson Turner, and whose name, however uncouth, ought to be gratefully remem- bered by British Algologists. Fig. 1. Uhodymexia bifida; unusually broad state. 2. The same ; normal variety. 3. Var. j3 :— all of the natural me. \. Fragment of the frond, showing the surface cellules. 5. Segment with tubercles. 6. Vertical section of a tubercle. 7. Spores from the same. 8. Segment with tetra- spores. 9. Tetraspores -.—all more or less magnified. Ser. MBLANOSPKRMEiE. ^™- Spharc/a , ■„',<■ . Plate XXXIII. CLADOSTEPHUS VERTICILLATUS, Ag. Gen. Char. Fronds inarticulate, rigid, cellular, whorled with short, jointed, subsimple ramuli. Fructification ; elliptical utricles, furnished with a limbus, pedicellate, borne on accessory ramuli. Cladostephtjs {Ag.) — from xXaSor, a branch ; and oT-e<£o f , a crown. Cladostephus verticillatus ; branches slender ; ramuli mostly forked, regu- larly whorled, the whorls at short intervals. Cladostephus verticillatus, Ag. Syn. Inlrod. p. xxv. Lyrigb. Hyd. Dan. p. 102. t. 30. Hook. M. Scot. vol. ii. p. 89. Qrev. II. Edin. p. 312. Harv.m Hook. Br. Ft. vol. ii. p. 322. Wyatt. Jig. Damn. no. 82. Han. m Mack. Ft. H ib. part 3 . p. 1 7 9 . Harv. Man. p . 3 6 . Cladostephus myriophyUum, Ag. Syst. p. 169. Ag. Sp. Alg. vol. ii. p. 10. Midi. 3rd Snppl. p. 24. kiitz. Phyc. Gen. p. 294. t. 18. f. 1. escr. Fronds rising from a hard disk, tufted, 3-12 inches long, much branched, furnished with an imperfect mid-rib below, which gradually be- comes fainter upwards, flat and membranaceous above ; the main stem simple, or forked 2—4" lines wide, alternately toothed. Branches issuing from the axils of the teeth of the main stem, tapering at the base, simple or subdivided, deeply pinnatifid; the /acinic ereeto-patent, hnear, entire for more than half their length, alternately toothed above, the larger ones pinnatifid, with toothed segments ; teeth very acute, erect. Fructification bom along the margin, or confined to the axils of the teeth, on slender, pel- lucid stalks, which are either simple or branched, solitary or tufted. Cap- sules somewhat pitcher-shaped, with very wide mouths, containing a cluster of dark red, pear-shaped spores ; stichidia lanceolate, nearly colourless, containing a double row of dark purple tetraspores. Substance cartilagineo- membranaceous subcoriaceous scarcely adhering to paper. Colour a deep vinous-red, becoming darker in drying. The smell is agreeably pungent, hut the taste is insipid. The genus Odonthalia, founded by Lyngbye on our 0. dentata, and nowcontaining three other species natives' of the Kamtschatkan sea, has been singularly misunderstood by Endlicher, who unites with these northern plants of leathery substance and closely cel- lular structure, several delicate tropical Algae with highly reticu- lated fronds, which have scarcely a character common with Odon- thalia except that minor one which gives the genus its name, — a toothed margin. Odonthalia dentata is peculiarly a northern plant. It abounds throughout the whole of the European, Northern, Atlantic, and North Seas ; and probably extends along the coast of Siberia and of North America. In the British Islands, it reaches, perhaps, its southern limit, and is most abundant on the coast of Scotland. In England it does not appear to be found south of Durham, and in Ireland, of Downshire. It varies very little in the frond, except that some specimens are more luxuriant than others. The mode of branching, and alternate pinnati-section is invariable ; but the fructification pre- sents some varieties. In some specimens, such as I have repre- sented, the stichidia are densely clustered, and, as well as the bunches of capsules, confined to the axils of the segments ; in others, both kinds of fruit are scattered along the margin. The specimens from which our figure is drawn were kindly communi- cated in a fresh state by Dr. Dickie, of Aberdeen. Kg. 1. Odonthalia dentata -.— statural size. 2. Lacinia; bearing capsules. 3 a Cluster of capsules. 4. Vertical section of a capsule. 5. Lacuna? with pods 6. Cluster of pods. 7. A pod or stichidium. 8. Tetraspores. 9. transverse section of the lower part of a branch -.—all more or less magnified. uxv Ser. CiiLOuo.srERMK.i:. Fam. Siphcmece. Plate XXXV. {A). CODIUM ADILERENS, Ag. Gen. Char. Frond green, sponge-like, (globular, cylindrical, or flatj simple or blanched), composed of tubular, interwoven, inarticulate filaments. Fructification ; opake vesicles attached to the filaments. Codium (StackA.) — from kuSiov, the skin of an animal. Codium adharem; frond forming a velvetty crust on the surface of rocks. Codium adherens, Jg. Sp. Jig. vol. i. p. 467. Ag. Syd. p. 17S. Ilarc. in Hook. Joiirn. vol. i. p. 305. Wyatt. Jig. Danm. no. 127. Hun-. Mini. p. 145. /. Jg. Medit. p. 22. Emit. ZrdSuppl. p. 21. KM;. Phjc. Gen. p. 309. Mont. PI. Cell. Conor, p. 183. A.GAEDHIA adherens, Cabrera, see.Ag. IIab. On marine rocks, near low-water mark. Perennial. Summer and winter. Rare. At Torquay, Mrs. Griffith. Scrmcn Cove, Land's End, Mr. Ilalfs. At the back of the pier on a vertical rock, at Gorran Haven ; and near the Bosand, Gerrans Bay, Cornwall, Mr. Peach. Falmouth Harbour, Miss Warren. GrBOGB. Pistr. Atlantic coasts of Europe, from the south of England to Spain. Mediterranean Sea. Mauritius? Canary Islands, Webb. Descr. Frond spreading over the surface of the rock in broad, indeterminate patches, of one, two or more feet in diameter, resembling "fragments of beautiful green velvet ", composed of an under layer of entangled and inter- woven, cylindrical filaments producing on the upper surface lineari-clavate, vertical branches, of equal length, paralielly arranged into the even velvetty surface of the frond, and being, as it were, the pile of the velvet. Substance soft and gelatinous, closely adhering to paper. Colour a brilliant green, when wet. I am indebted to Mr. Peach of Fowey for living specimens of this curious plant, which he finds in great perfection at Gorran Haven. It appears to be of slow growth ; for Mr. Ralls informs me, that patches cut out one year, are but partially filled up after twelve months. I am not quite certain that the Mauritius speci- mens, formerly described by me, are identical with the European. J. Fig. 1. Codium adh.erens: — natural size. 2. A portion: — magnified. 3. Filaments : — more highly magnified. Plate XXXV. (B). CODIUM AMPHIBIUM, Moore. Comoi ampMbium; fronds minute, erect, cylindrical, simple, obtuse, aggregated in widely spreading strata. Codioi ampMbium, Moore et Han-, in Ann. Nat. Hist, vol. xiii. (is 11) p. 321. pi. 6. Hab. On turf-banks at extreme high-water mark, near Eoundstonc, Galway, Mr. Mc' Calla. Geogk. Distk. West of Ireland. Descr. Stratum indefinite, composed of entangled filaments, spreading over the surface of the bog. Fronds rising above the stratum, like papillae, cylin- drical or clavate, from a line to nearly half an inch in height, and from a quarter-line to more than a line in diameter, erect, distinct from each other (not massed together), obtuse, simple ; their axis composed of branched, interwoven, irregular fibres, which throw off to the circumference club- shaped ramuli, of the same nature, and nearly the same form, as those of C. tommtomm. Colour a brilliant green. Substance soft. Codiitm ampMbium was discovered by Mr. Mc' Calla in October, 1843, spreading in patches of great extent along the edge of the sea, over the surface of a turf-bog which meets the shore at Roundstone Bay. In this situation the plant is exposed alter- nately to the influence of salt and of fresh water, and, it woidd appear, is even affected by atmospheric changes : for, its dis- coverer has observed, that " in dry weather it loses all its charac- ters, the frond shrinking to a mere nothing, but on the return of moisture it immediately gets fresh again". Specimens will, I understand, be published in the sec. mil volume of M'Calla's ' Algie Hibernica" . II. Fig. 1. CODIUM AMPHIBIUM: — natural size. -'. Two of the fronds: — magnified ■'<■ Filaments from the same : — more highly magnified. Ser, Rhodospermm. F ;un . Gloiocladea. Plate XXXVI. NEMALEON MULTIFIDUM, / Ag. Gen. Char. Frond cylindrical gelaihoso-cartilaginous, clastic, solid; axis columnar, dense, composed of closely packed, longitudinal, inter- laced filaments; the periphery of elongated, horizontal, dichotomous filaments, whose ultimate ramuli are moniliform and coloured. Fruc- tification; globular masses of spores (favellidia), attached to the filaments of the periphery. Nemaleon (Tozzetti.) — from *}/«, a thread, and \rj\ov, a crop ; crop of threads. Nemaleon multifidnm ; frond dichotomous, slightly branched, dull purple; the axils rounded. Nemaleon niultifidum, /. Ag. in Linncea, vol. xv. p. 453. Midi. 3rd Suppl. p. 37. Mesogloia multifida, Ag. Syst. p. 50. Berk. Alg. t. 16. f. 1. Harv. in Hook. Br. Ft. vol. ii. p. 385. Mack. Fl. Hib. part 3. p. 185. Wyatt. Alg. Damn. no. 98. Harv. Man. p. 47. Mont. PI Cell. Conor', p. 189. Mesogloia Balani, Carm. MSS. Chordaria multifida, Lyngb. Hyd. Dan. p. 51. Fl. Dan. 1. 1669. Chjetopiiora multifida, Hook. Fl. Scot, part 2. p. 76. Eivularia multifida, Web. et Mo/ir. Roth. Cat. Bot. vol. iii. p. 335. Helminthora multifida, Kiitz.Phyc. Gen. p. 391. t. 44. f. 3. Var. /3, simplex ; frond simple or nearly so. Nemaleon lubricum, Duby. ? et Auct. Hab. On rocks, Balani, and shells (frequently on Mytilus rugosus), near low-water mark, in exposed situations. Common along the western shores of Scotland and Ireland. Downshirc, Mr. Templeton. Tor- quay Mrs. Griffiths. Falmouth, Miss Warren. Balbriggan, Miss Gower. Var. /3, at the Land's End, Mr. Ralfs. Geogr. Distr. Atlantic shores of Em-ope. Mediterranean sea. Canary Islands, Webb. Descr. Root a fleshy, expanded disc. Fronds dull purplish brown, 3-10 inches long, 1-2 lines in diameter, cylindrical, very elastic, firmly gelatinous or somewhat cartilaginous, generally forked near the base, and repeatedly forked at long intervals upwards, but varying much hi the degree of furca- tion. Axils all remarkably wide, and rounded ; apices but slightly tapered, blunt. Axis about one fourth of the diameter of the frond, very dense, compared by Agardh to a column, and by Carmichael to a " medullary cord ", composed of closely adherent slender filaments, from wliich issue the long, horizontal, dichotomous filaments of the periphery, whose lower ramifications are colourless, with subcylindrieal joints ; their upper, and terminal, coloured and beautifully beaded. Occasional reflexed, rout-like K 2 ram'uli or processes may be observed on the peripheric filament-. FaveUidio dark red globose, seated among the beaded apices, composed of innumerable angular snores. In var. ft the frond is either quite simple, or merely forked at the base. This plant, which is found on most of the rocky shores of Europe, and probably identical with the Mediterranean species which I have ventured to unite with it, was first described by Weber and Mohr in their 'Travels in Sweden'*, and soon after- wards taken up by Roth in his ' Catalecta Botanica'. It occurs in considerable plenty on our western shores, growing near low water mark, either on the bare rocks, or on shells attached to them ; and generally in situations where it is exposed to the air for a few hours, and at the same time subject to be lashed by the waves. Mr. Thompson, on the contrary, finds it at New- castle, Co. Down, growing in very shallow tide-pools on granite rocks, and there only. Except in the degree of ramification, it has no varieties •. and characters, drawn from the more or less frequently forked frond, can scarcely, I fear, be depended upon ; for in the same locality I have found a very considerable difference in this respect. Mr. Ralfs observes that at the Land's End the specimens are either quite simple, or merely forked at the base ; and these we regard as being identical with the Mediterranean N. lubricum. Again, I possess°a specimen from the Mediterranean marked .V. lubricum by Professor J. Agardh, which is repeatedly dichotornous. I confess that I am at a loss to see on what characters authors contend for the existence of two species. There is no difference of structure that I can perceive, and it would seem that rami- fication is equally disregarded as a character by Agardh, as by myself. The specimens here figured represent the usual size and degree of branching which the plant attains on the west coast of Ireland ; Scotch and Baltic specimens arc often much more divided, more slender, and of smaller stature. Fig 1 Nf.mai.eon MULTIFIDTJM, growing on Mytilus rvffosua:— natural Wee. ^ •> Filaments of the periphery, with a small portion of the axis. 3, 4. Side and front views of the faveUidium, surrounded by beaded filaments. 5. Spores: — all magnified. * ' Reise durch Schweden'. [7nr< xxxv/r. Ser. ^If.i.anospermle. Fain. 8phaeelarie„. p. 37. Wyatt. Jig. Damn. no. 361. Ag. Jig. Medit. p. 29. Endl. 3rd Suppl. p. 23. Meneg. Jig. Ital. et Balm, p. 314. Sphacelaria disticha, Lyngb. I.e. p. 101. t. 31. J. Jg. Sp. Alg. vol. ii. p. 26. Harv. in Hook. Br. Fl. vol. ii. p. 323. Sphacelaeia scoparioides, Lyngb. 1. c. p. 107. t. 32. C. Ag. Syst. p. 165. Cekamium scoparium, Roth. Cat. But. vol. iii. p. 141. Ag. Syn. Hook. Fl. Scot. part. 2. p. 86. Conferva scoparia, Linn. Syst. Nat. vol. ii. p. 720. Hnds. Fl. Angl. p. 595. Dghtf. Fl. Scot. p. 981. With. vol. iv. p. 131. Bilhc. Conf. t. 52. E. Bot. t. 1552. Conferva marina pennata, Billen. t. 4. f. 23. Stypopodiim scoparium, Kutz.Phgc. Gen. p. 293. t. 18. f. 2. Hab. On submerged rocks, within and beyond the influence of the tide. Generally distributed along the coasts of the British Islands ; most common in the south. Geogr. Distr. Atlantic coasts of Europe from Norway to Spain. Baltic and Mediterranean Seas. Canary Islands, Webb. Cape of Good Hope, W. H. H. Pi: scr. Root, and lower part of the stems invested with a thick coating of woolly fibres. Stems 2—4 inches high or more, shaggy, robust, cither much and irregularly divided, or subsunple, densely set with quadrillions, pinnate or bi-pinnate branches, which spread from the summits of the main divisions in broad, brush-like, rigid tufts. Pinna either short, simple, and spine- like or elongated, and again pinmdate. Joints longitudinally striate. A section of the stem and its accessory fibres (fig. 5), exhibits an elegant lace- work of square cellules in the centre of the stem, aud of each separate fibre. So different from each other are the summer and winter states of this plant that the accurate Lyngbye may well be forgiven for considering them to be distinct species. Few persons on inspec- tion of our plate, would suppose that the bushy and broom-like upper figure, was identical in species with the feathery plant re- presented below ; even their microscopic characters are widely dissimilar. Yet, observation, the true test of species, has traced the one form into the other ; and I possess a suite of specimens communicated by Miss Cutler and Mrs. Griffiths, which clearly demonstrate the transition. Sphacelaria scoparia has been long known to botanists, having been noticed by Bauhin, and figured by Dillenius in his admi- rable work. It is very common on the several coasts of Europe, both Atlantic and Mediterranean, and probably extends to other tropical shores besides those of the Canary Islands. I have gathered it in two localities at the Cape of Good Hope. Further south, its place is taken by an analogous form (S. funiadaris, Mont.), which is found at the Auckland Island, and in New Zea- land, in which Island some other remarkable Sphacelaria occur. Of these the most curious is S. hordeacea, whose branches are tipped with spikes of utricles, subtended by ramuli, and closely resembling miniature ears of barley. Other species of the genus inhabit every zone, from North Cape to Cape Horn ; but tropi- cal algae have been, as yet, so imperfectly investigated, that it is premature to assert to which zone the maximum of the genus belongs. At present the evidence is in favour of the temperate zones of the northern hemisphere. Professor Kiitzing has, in his ' Phycologia Gencralis,' constituted S. scoparia the type of a distinct genus, and S.flicina that of another. The grounds of such separation are, in my opinion, very insufficient to warrant the dismemberment of so natural and well defined a group as the Sphacelaria of Lyngbye appear to be. Fig. 1. Sphacelahia scoparia; in summer: — natural size. 2. Branchlet of the same: — magnified. 3. S. scoparia; in winter: — natural she. 4. Branch- let of the same. 5. Cross section of the stem, surrounded by accessory fibres : — magnified. /■/,,/, \ \\r///. Ser. lliiotfosFERME.i;. Pain. Gloiocladea. Plate XXXVIII. NACCARIA WIGGHII, Endl. Gen. Char. Frond cylindrical or flat, filiform, solid, rose-red; central cel- lules large, empty ; those of the surface minute. Hamuli composed of jointed, dichotomous, verticillate filaments. Fructification ; groups of spores (favellidia) contained in swollen ramuli. Naccaria {Endl.) — in honour of F. L. Naccari, an Italian botanist, and author of ' Algologia Adriatica ', and other works. Naccaria Whigglm; frond cylindrical; branches irregular, subalternate, attenuated; ramuli spindle-shaped, quadrifarious. Naccaria Wigghii, Endl. Gen. PI. no. 68. Endl. Zrd Stippl. p. 37. Harv. Man. p. 50. /. Ag. Alg. Medit. p. 86. Kiltz. Phyc. Gen. p. 391. Ch.etospora Wigghii, Ag. Syst. p. 146. Grev. Alg. Brit. p. 153. 1. 16. Hook. Br. M. vol. ii. p. 306. Harv. in Mack. Fl. Hib. part 3. p. 187. Focus Wigghii, Turn, in Lin. Trans, vol. vi. p. 135. t. 10. Syn. Fnc. vol. ii. p. 362. Host. Fuc. t. 102. Sm.E. Bot. t. 1165. Cladostephus Wigghii, Spreng. Syst. Feg. vol. iv. p. 347. Hab. On marine rocks, at and beyond the extreme limit of the tides. Annual. Summer. Yery rare. Yarmouth, Mr. Lilly Wigg. South coast of England, in several places; not unfrequent, Mr. Boner, Mrs. Griffiths, Sfc. Bantry Bay, Miss Eutchins. Kilkee and Wick- low, W. E E. Belfast Bay, Mr. W. Thompson. Jersey, Miss White, Miss Turner. Geogr. Distr. Atlantic shores of Europe from England to Spain. Mediterra- nean sea, at Nice, Risso. Descr. Root discoid. Fronds 6-12 inches high, cylindrical, filiform, much branched. Main stein from half a line to a line in diameter below, gradually attenuated upwards, undivided, or variously cleft, or subdichotomous, beset with very numerous, quadrifarious, lateral branches. Branches alternate, or issuing irregularly, very various in length, simple, or slightly divided, bearing a second or third set of similar but shorter and more slender brancbleta ; which, including all the younger parts of the frond, are beset on all sides with minute, slender ramuli, tapering to each end, and 1-2 lines in length. The stem and branches are solid, composed internally of very large, hyaline, polygonal, cells, surrounded by others of small size, and a periphery com- posed of minute cellules. The large interior cells, seen through the coat of the frond, give the surface, under a low power of the microscope, a reticu- lated appearance. The rainuli consist of whorls of horizontal, radiating, dichotomous, jointed filaments, closely packed together, and issuing from a slender, cellular axis. When in fructification, the ramuli become wider in the middle, taking a spindle shape, and spores of an oblong, pyriform shape, are formed at the bases of the whorled filaments. The colour is a brilliant, rose-red, the substance irelntinoso-membranaceous, and the plant adheres to paper in drying. This charming plant, as rare as it is beautiful, was discovered by Mr. Lilly Wigg on the Norfolk shore, about the year 1790, and first described by Mr. Dawson Turner in a paper read before the Linnsean Society in 1801. Since that period it has been detected on many different parts of the English and Irish coasts ; but not as yet, that I am aware of, in Scotland. Some doubts respecting its true affinities have been entertained by modern systematists, but all seem now to be agreed in referring it to the neighbourhood of MesogMa ; an affinity suggested by its first describer ; long neglected, and afterwards independently taken up by Mrs. Griffiths, under whose sanction I referred it in 1830 to its present position. The structure of the greater part of the frond is indeed very different from that of the Gloiocladea ; the peripheric filaments which form so remarkable a feature in that family, being wholly wanting in the stem and branches ; but the habit and gelatinous substance are very similar, and the structure of the ultimate raniuli agrees very nearly with that of the whole frond of MesogMa. In the Mediterranean it appears to be of as unfrequent occur- rence as on the British shores, and has only, as yet, been found by M. Risso. A second species of the genus, N. Schousboei, J. Ag., is found on the shores of Morocco ; — it is said to have flat, many times pinnated fronds. Pig. 1. Naccaria Wigghii : — natural si:/-. 2. Part of a branch. 3. One of the fruiting raniuli. 4. Filaments of which this is composed, with spores in situ. 5. Spores removed. 6. Transverse section of the stem. 7. Lon- gitudinal section of the same : — all magnified. I'tal< I A Hi K> •< \ % \ . Ser. Chlorosi'kkmk.i:. I'uui. Ulvacea. Plate XXXIX. ULVA LINZA, Linn. Gen. Char. Frond membranaceous, green, expanded, plane (in some cases saccate when young), composed of irregular cellules. Fructification ; granules, often arranged in fours, scattered over the whole frond. Ulva — supposed to be from VI, water in Celtic. Ulva Lima ; frond linear lanceolate, acute, crisped at the margin, com- posed of two membranes closely applied. Ulva Linza; Linn. Sp. PI. p. 1633. LigMf. M.Scot, p. 973. Fl. Dan. t. 889. Roth. Cat. vol. ii. p. 246, and vol. hi. p. 330. Ag. Syn. p. 40. Spec. Alg. vol. i. p. 413. Lgugb.Hyd.Dan.ip.32. Grei\ Ft. Edin. p. 299. Alg. Brit. p. 173. Hook. Br. Fl. vol. ii. p. 311. Harv. in Mack. Fl. Hib. part 3. p. 243. Man. p. 171. Wyatt. Alg. Damn. no. 164. /. Ag. Alg. Miedit. p. 17. Solenia Linza, Ag. Syst. p. 185. Phycoseris Linza, Kutz.Phyc. Gen. p. 297. Tremella marina fasciata, Dill. Muse. p. 46. t. 9. f. 6. Hab. On rocks and stones in the sea, at half-tide level. Annual. Summer. Not uncommon. Geogr. Distr. Atlantic and Mediterranean shores of Europe. New Zealand. Descr. Root a small callus. Fronds from six inches to one or even two feet in length, and from half an inch to two inches in width, linear-lanceolate, attenuated towards the base, and more or less tapering at the apex, waved and curling at the margin, membranaceous ; composed of two distinct membranes closely applied together. Fructification scattered over the whole frond, to which it gives colour. Colour, a full, brilliant grass-green, fading in age. Substance thin, adhering to paper in drying. This is one of the most beautiful of the British Ulvae, as it is also one of the less common species. Its gracefully shaped, and elegantly curled fronds look peculiarly well as the plant waves freely in the water. It has long been known to botanists, having been distinguished by Linnaeus, and has been found on very distant shores. It in- habits the Southern as well as the Northern Oceans, probably extending nearly as far as vegetation extends to the south, though as yet we have not had it from any locality south of the Bay of Islands. The frond consists of a double membrane, so that it has been by some authors associated with the Enter omorpha, to which group it affords a direct passage i. Fig. 1. Ulva Linza, tuft of fronds : — natural size. 2. A portion of the mem- brane : — ma Ser. Riiodospetimkve. Pain. Rhodomelea. Plate XL. DASYA OCELLATA, Harv. Gen. Char. Frond filamentous; the stem and branches mostly opake, irregularly cellular (rarely pellucid, longitudinally tubed), composed internally of numerous parallel tubes; the ramuli jointed, single- tubed. Fructification two-fold, on distinct plants ; 1, ovate capsules {ceramidia) furnished with a terminal pore, and containing a tuft of pear-shaped spores; 2, lanceolate pods {stichidia), containing tetras- pores ranged in transverse bands. Dasya [Ag.) — from Sacris hairy. Dasya ocellata ; stems subsimple, beset on all sides with long, erecto- patent, dichotomous, pencilled ramuli; articulations three or four times longer than broad ; pods linear-lanceolate, attenuated, tapering to an acute point. Dasya ocellata, Harv. in Hook. Br. 17. vol. ii. p. 335. Mack. Ft. Hib. part 3. p. 210. Wyatt, Alg. Banm.no. 179. Harv. Man. p. 97. Kiits. PAyc. Gen. p. 414. Dasya simpliciuscula, Ag. Sp. Alg. vol. ii. p. 122 (1827). /. Ag. in Linn. vol. xv. p. 35. Alg. Medit. p. 118. Ceramium ocellatum, Gratel. in Hist. Soc. Med. Montp. 1807. p. 34. Hutchinsia ocellata, Ag. Syst. p. 157 (1S24). Hab. On mud-covered rocks in the sea, rare. Annual. Summer. Abundant on the Pier, Torquay, Mrs. Griffiths. Whitsand Bay, Br. Walker Arnott. Wicklow, W. II. H. Smerwich Harbour, Kerry, Mr. W. Andrews. Balbriggan, Mrs. Gregg and Miss Gower. Trevol, Rev. W. S. Hare. Geogr.Distr. Atlantic coasts of France and Spain. Mediterranean Sea. South of England. East and South of Ireland. Descr. Root a small disc. Fronds one, two, or three inches high, tufted. Stems, in the smaller specimens, simple or once forked at the base ; in the larger, twice or thrice forked, and occasionally having a few lateral, simple branches ; as thick as hog's bristle, opake, cartilaginous, without external joints, the surface cellules being irregular. Ramuli clothing the stem and branches from the base to the apex, at which point they are remarkably dense, inserted quadrifariously, 3-5 lines long, slender, erect, several times forked near their base, cylindrical, the apices much produced, but not tapering, blunt. Articulations of the ramuli 3-4 times longer than broad, single- tubed. "Fructification ; Ceramidia (not yet found on British specimens). Stichidia ox pods shortly pedicellate, borne on the ramuli, narrow, lanceolate, gradually tapering from the middle to an acute apex, straight or gracefully curved, slightly constricted at close intervals, producing in transverse bands, numerous small dark-purple tetraspores. Colour a brownish or a bright purple. Substancr membranaceous, adhering to paper. This little plant here figured, was first described by Grateloup, in the year 1807, under the specific name which I adopt in pre- ference to that proposed by Agardh twenty years subsequently. By the term ocellatum, Grateloup no doubt intended to allude to the eye-like spots caused by the density of the ramuli at the tips of the branches. The branches, indeed, when the plant is displayed on paper resemble delicate feathers, each marked with an eyelet. When growing, Mrs. Griffiths compares them with equal propriety, to the brushes with which bottles are cleaned Dasya ocellata was added to the British Flora by Mrs. Griffiths, who found it plentifully fringing the base of the small harbour-pier at Torquay, in which situation it is constantly covered with mud, from which obscurity, a less zealous and acute observer, would not have redeemed it. It can only be approached in a boat, at extreme low water. In this situation it has continued to grow for several years. Of recent date it has been discovered in two or three Irish localities, at either side of the kingdom. From one of these, Balbriggan, the specimen here represented, and which I owe to the kinduess of Miss Gower, was procured. It is of the largest size that I have seen, the majority of British individuals being not above an inch and a half in length, and either quite simple or scarcely branched. Pig. 1. Dasya ocellata; a tuft: — natural size. 2. Portion of a branch 3. Hamulus with pods ; both magnified. Ser. Melanospermk.i . Fam. Chordariea. Plate XLI. (A). MYRIONEMA LECLANCHERII, Haw. Gen. Char. Minute Parasites, consisting of a mass of short, erect, simple, jointed filaments, which spring from a thin expansion formed of de- cumbent, cohering filaments, spreading in patches on the surface of other Algie. Spores oblong, affixed either to the erect, or to the decumbent filaments. Mytuoneha ( Grev.) — from iivpiot, a thousand, and vruia, a thread. Mtrioxema Leelancherii ; patches orbicular, thin, and with few vertical filaments toward the edges, convex with crowded filaments in the centre ; spores on long pedicels affixed to the decumbent filaments, obovate. Rivularia Leelancherii, Cliauv. — see. Lenorm. in litt. Has. On decaying fronds of Rhodymenia palmata, probably common. Annual. Autumn. Torquay, Mrs. Griffiths. Down coast, Mr. W. Thompson, 1835. Geogr. Distr. Shores of Europe. Descr. Patches from a line to a quarter of an inch or rather more in diameter, orbicular, or slightly irregular in form, composed at first of decumbent filaments radiating from a centre, and spreading on the surface of the Rhodymenia, closely cohering together into a thin membranous expansion, which is finely serrated at the edges. As the plant advances to perfection, vertical filaments, closely set together, spring in the centre of the patch, where they form an umbo, and gradually are developed outwards, becoming shorter and shorter as they approach the edge. Beyond this umbo a wide margin, destitute of vertical filaments or with a few scattered short ones, extends. Spores obovate, on long pedicels, or on the apices of abbreviated filaments. At other times — and, indeed, more frequently — some of the vertical filaments are found altered into lanceolate pod-like bodies, repre- sented at fig. 4, jointed, but seemingly destitute of sporaceous matter. Co/our olive brown. In Autumn the fronds of the common Duke (Rhodymenia pal- mata) in passing to decay are commonly found covered with roundish olive spots, which, by a hasty observer may be over- looked as being nothing more than incipient mortification. By placing a small portion of such a spotted frond under the micro- scope, the beautiful parasite here figured is brought to light. It was first pointed out to me by Mrs. Griffiths in 1845, who found it very plentifully at Meadfoot, near Torquay, and who received specimens identical in every respect from M. Lenormand under the name here quoted. I am not aware whether it has been published by Chauvin. It is nearly related in structure to M. slrangulans but differs something in habit, forming a much larger and thinner spot on the fucus. A. Fig. 1. Portion of the frond of Rkodymenia palmata with Myrionema Leclan- cherii growing upon it: — natural she. 2. Myrionema Leclancherii. 3. Por- tion of the same. 4. Filaments from the same. 5. Filaments and spores in situ : — all more or less magnified. Plate XLI. (B). MYRIONEMA PUNCTIFORME, Haw. Myrionema punctiforme ; patches globose ; filaments tapering to the base ; spores llnear-obovate, affixed to the vertical filaments near their base. Myrionema punctiforme, Harv. in Hook. Br. Fl. vol. ii. p. 391. Man. p. 124. Linkia punctiformis, Lyngb. Eyd. Dan. t. 66. Carm. Ahj. App. ined. cum icone. Hab. Parasitical on the Florideae. Annual. Summer and Autumn On Chrysimenia clavellosa, at Appin, Copt. Carmichael. On Ceramium rulrwn, at Torquay, Mrs. Griffiths. Geogr. Distr. Shores of Europe. Descr. Fronds or patches very minute, half a line or less in diameter, flatfish or globose, composed of vertical threads radiating from a smalf base. Fila- ments slightly tapering to the base, with joints twice or thrice as long as broad. Spores sessile near the bases of the erect filaments, very narrow in proportion to their length, and much attenuated at the base. This little parasite is obviously nearly akin to M. Leclancherii, from which its globose fronds or patches, and more narrow spores distinguish it. It comes nearer to M. slrangulans, but differs in the position of the spores. The only specimens which I have seen were collected by Mrs. Griffiths several years ago. They were found on Ceramium rubrum, which they covered nearly as closely as the warts of fructification cover Stihphora rhieodeg. Probably, if looked after, it may be found on many of our coasts. It was added to the British Flora by the late Capt. Carmichael, of Appin, whose many discoveries in minute botany have ren- dered his name familiar to most algologists. B. Fig. 1. Ceramium rubrum with Myrionema punctiforme parasitical upon it : — natural size. 2. Branch of the same. 3. Vertical section of part of the Myrionema. 4. Filaments with spores. 5. A Spore: — all more or less highly magnified. I'/ ,,7-, < XL/7. Ser. Rhodosperme4£. Farm Chond Plate XLII. CHYLOCLADIA REFLEXA, lenorm. Gen. Char. Frond tubular, constricted at regular intervals, and divided by internal diaphragms into joints, filled with watery juice, and traversed by a few longitudinal filaments ; periphery composed of small, polygonal cellules. Fructification of two kinds, on distinct individuals; 1, spherical, ovate, or conical capsules (eeramidia) con- taining a tuft of wedge-shaped seeds, on a central placenta. 2, tri- partite tetraspores, immersed in the smaller branches near their apices. Chylocladia (Grev.) — from x v ^° s ,juict, and kX58o?, a branch. Chylocladia refiexa ; frond membranaceous, purple ; lower branches cylindrical, slender, arched, attaching themselves by short ramuli tipped with discs ; secondary branches simple, mostly secund, nioni- liform, spindle-shaped ; ramuli few, scattered, patent or recurved. Chylocladia retlexa, Lenorm. Besm. PI. Crypt, no. 865. Lomentaria refiexa, Chant. Alg. de Norm. Lomentaria pygma?a, Buby. Bot. Gal. (excl. Syn.) Hab. On rocks in the sea near low-water mark. Annual. Summer. Very rare. Hagington near Ilfracombe, Miss Amelia Griffiths, (Julv ' 1834). Eoundstone Bay, Mr. Mc'Calla. Geogr. Distr. Coast of Normandy. North coast of Devon. Descr. Root an expanded, fleshy disc. Frond from two to three inches high, half a fine to a line in diameter, branching from the base in an irregular manner ; the lower or main branches cylindrical, scarcely constricted, slender, arched, zigzag, forming successive arcs in one direction, and furnished at the concave side of the arc with short holdfasts, tipped with discs, by means of which the frond attaches itself to neighbouring objects, in a creeping manner ; the upper or secondary branches springing from the arched ones, either two or three from one point or solitary, generally uni- lateral, simple, spindle-shaped, moniliform, constricted at regular intervals into joints about once and a half as long as broad, the upper joints gradually shorter to the tips. Ramuli few, short and mostly secund, patent or re- curved, sometimes but rarely binate. Capsules spherical, with a pellucid border, containing a very dense mass of angular seeds. Tetraspores abun- dantly produced in the tips of the branches and ramuli. Colour a dull purple. Substance membranaceous, adhering to paper. A small specimen of this interesting plant was communicated to me by Mrs. Griffiths some years ago, under the impression that it was a new species ; but I delayed to describe it until more numerous specimens, and in a more perfect state, should be discovered. I was not then aware that it was the same as a plant which occurs in several places on the coast of Normandy, and of which specimens have been since published in Desma- ziere's Cryptogames of France. More lately, Mrs. Griffiths has allowed me to take a figure from specimens preserved in her Herbarium, found by Miss Amelia Griffiths at Ilfracombe ; in which situation it appears to be of great rarity. At the time the figure was made, I was not aware that a spe- cimen found by Mr. Mc'Calla in 1840 existed in Dr. Coulter's Herbarium, among the numerous examples of C. Kaliformis, which I the more regret as an earlier knowledge of it would have enabled me to introduce the capsular fruit into my plate. It is abundantly covered with capsules, which have not been found on any of the Ilfracombe specimens. As a species, it is, perhaps, more nearly allied to C. Kaliformis than to C. parvula, although at first signt it looks more like the latter. Its slender, main branches, and the remarkable disk-like processes by which they attach themselves at intervals, taken with the small size, irregular branching, and less gelatinous nature, offer its best distinguishing marks. The different form of the capsules affords alone a sufficient character to separate it from C. parvula. Figs. 1, 2. Chylocladia keflexa: — natural size. 3. Part of the stem, with branches, and disks. 4. Tetraspores : — both magnified. xzm. Ser. ( aioEOSPERMi i - '' mn - ' Plate XL1II. ENTEROMORPHA ERECTA, Hook. Gen. Char. Frond tubular, membranaceous, of a green colour and reticu- lated structure. Frw tification ; granules, commonly in fours, con- tained in the cellules of the frond. Enteromorpha— from eVepoy, an enirail, and nopfa, /">'">> 0I ' Enteromorpha erecta ; frond cylindrical, filiform, slender ; branches erect, opposite or alternate, all attenuated to a fine point ; ramuli capillary, erecto-patent ; reticulations rectangular, nearly square, arranged in many longitudinal lines. Enteromorpha erecta, Hook. Br. Fl. vol. ii. p. 314. Wijatt. Alg. Damn. no. 166. Harp. Man. p. 175. Enteromorpha clathrata, jS. erecta, Oreo. Alg. Brit. p. 181. Hare, in Mack. Fl. Hih. part 3. p. 242. Scytosiphon ereetus, Lyngb. Hyd. Dan. p. 65. t. 15. Fistdlaria erecta, Grev.Fl.Edin. p. 300. Solenta clathrata, var. confervoidea, Ag. Syst. Alg. p. 187. Hab. On rocks in the sea, and in rocky submarine pools, at about half- tide level ; also dredged in 4-6 fathom water. Annual. Spring and Summer. Not uncommon. Geogr. Distr. The temperate and tropical zones of both hemispheres. Descr. Frond from four to eight inches in height, cylindrical, varying from the thickness of a hog's bristle to half a line or a line in diameter. Stem usually undivided, tapering at the base and apex to a tine point, closely set through- out the greater part of its length with opposite or alternate, simple, erect or erecto-patent branches, the lowermost of which are longest, the upper gradually diminishing towards the upper part of the frond, all of them attenuated, like the stem, to an exceedingly fine point. The branches are well furnished with slender, subdistichous or irregularly quadrifarious, setaceous, short ramuli, and have a beautifully feathery appearance. The structure consists of a delicate membrane, composed of square or oblong- rectangular cells, each containing a dense endochrome, which in a state of fruit separates into about four distinct granules. Colour a brilliant grass- green. Substance glossy, tender, and adhering to paper in drying. I have cautiously confined myself in making the above des- cription to the typical variety of this variable plant, a specimen of which, communicated by Mrs. Griffiths, is represented in our plate. In the "Manual" I have recorded my agreement in opi- nion with Dr. Grevdle, Sir Wm. Hooker, and, indeed, with the majority of botanists, that the several forms called E. erecta, E. clathrata, and E. ramulosa are but different states of one species ; and may now add that E. Linhiana, of Greville, and E. Hop- kirkii, Mc'Calla, are, in my judgment, equally doubtful. Still, as the plants which have received these names present very diffe- rent aspects, and from their size cannot be presented in the same plate, it is my intention to give separate figures and descriptions of all of them, and then to leave it to the judgment of botanists whether to adopt the notion of one protean species, or of many less variable, but still anastomosing species, or, more properly, races. E. erecta is one of the most beautiful forms, particularly when dredged in deeper water than comes within the usual tide range. Such are the specimens represented in our plate, which were dredged in Torbay. In these the ramuli are even more feather}' than the figure exhibits. Fig. 1. Enteromoepha erecta: — natural sice. 2. A branch: — magnified. 3. Portion of the membrane: — highly magnified. r/« /, x/jt: Scr. Eiiodosperjie.k. Fam. Delesseriece. Plate XLIV. PLOCAMIUM COCCINEUM, Lyn 9 b. Gen. Char. Root fibrous. Frond pinky-red, linear, compressed or flat, ribless, or faintly nerved, cellular, distichously much branched ; the ramuli alternate, or secund, acute. Fructification of two kinds on distinct individuals ; 1, spherical tubercles (coccidia) sessile or stalked, marginal or axillary, containing a globular mass of angular spores ; 2, lateral or axillary, simple or branched pods (stickidia) containing a double or single row of transversely parted, oblong tetraspores. Plocamium {Lamour. ref.), — from TrXdra/iot, braided hair. Plocamium coccineum; frond narrow, cartilaginous, piano-compressed; branches irregularly alternate, patent ; ramuli subulate, secund, three or four consecutively, pectinate on their inner edges ; tubercles lateral, sessile ; stichidia scattered, lanceolate, simple or branched. Plocamium coecineum, Lyngb. Hyd. Ban. p. 39. t. 9. Gret>. Alg. Brit. p. 98. t xii. Hook. Br. Fl. vol. ii. p. 293. Harv. in Mack. Fl. Hib. part 3. p. 195. Wvait, Ala. Banm. no. 20. Harv. Man. p. 65. Ag. AUj. Mcdd. p. 155 Endl, 3rd Suppl. p. 52. Kiitz. Fliyc. Gen. p. 449. t. 64. Mont. PL Cel. Canar. p. 152. Hook.fil. Fl. Antarct. vol. l. p. 186. Plocamium vulgare, Lamour. Ess. p. 50. Gail. Bid. Sc. Nat. vol. liii. p. 368. Plocamium Lyngbyanum, Kiitz. 1. c. p. 450. Plocamium Biuderianum, Kiitz. 1. c. p. 450. Delesseria coccinea, Ag. Syn. p. xiv. Hook. Fl. Scot, part 2. p. 101. Grev. Fl.Edin. p. 294. Delesseria Plocamium, Ag. Sp. Ahj. vol. i. p. 180. Syst. p. 250. Mart. Fl. Brazil, p. 42. Ceramium Plocamium, Roth.Fl. Germ, vol.iii. p.458. Cat.Bot. vol.ii. p. 161, and vol.iii. p. 107. Fucus coccineus, Suds. Fl. Ang. p. 586. Linn. Trans, vol. iii. p. 187. Stock. Ner. Brit. p. 106. Turn. Syn. vol. ii. p. 291. Hist. t. 59. E. Bot. t, 1242. Fucus Plocamium, Gm. Hist. p. 153. 1.16. f.l . Lightf. Fl. Scot. vol. ii. p. 957. Esper. Ic. vol. i. p. 18. t. 2. 3, uncinata; small, slender, very flexuous, entangled and irregularly branched; ramuli patent or frequently hooked back. Plocamium fenestratum, Kiitz. Phyc. Gen. p. 450. Hab. On submarine rocks and the larger Algse, generally growing beyond the usual tide-level. Perennial. Summer and Autumn. Common on the British shores. Geogr Distu. Abundant in the northern and southern temperate zones Brazil, Martins. Cape Horn, Br. Hooker. Auckland Island; New Zealand; Tasmania. Cain- of Good Hope. k -2 Descr. Root consisting of branching fibres, matted together. Fronds tufted 2-12 inches long, exceedingly branched, and bushy, compressed or nearly flat, two-edged, narrow, linear, irregularly divided ; main stems from half a line to nearly a line in breadth, alternating or subdichotomously branched ; branches distichous, frequent, often secund, patent, bearing one or more sets of similar lesser branches. Hamuli subulate, acute, patent, flinging the edges of the branches, secund, three or four at one side, and then three or four at the other ; the lowest in position of each set simple, rarely crenulate along its outer edge, the rest pectinate along their inner edge with subulate teeth, which, in luxuriant specimens, bear a second or third series. Tuber- cles solitary, sessile on the edges of the stem and branches. Stidtidia lan- ceolate or dichotomous, scattered along the edges of the upper branches, occasionally tufted, containing several oblong tetraspores, each marked by three pellucid transverse lines or zones, and finally separating into four granules. Colour a fine transparent red, between crimson and scarlet: Substance cartilagineo-membranaceous, adhering, but not very closely, to paper. A well-known, abundant, and beautiful species, and an especial favourite with amateur weed-collectors, and manufacturers of sea-weed pictures. It is also a very widely dispersed plant, being found in greater or less abundance and luxuriance, but with the same essential characters, in all waters from the North Cape to Cape Horn, in which last mentioned locality Dr. Hooker gathered specimens, in every respect identical with our most strongly growing British individuals. With the exception of Qosjaelqffic species, the genus Ploca- mium, in which I include the Thamnophora of Agardh, and the Thamnocarpus of Kutzing (not of Harv. in Hook. Ic. Plant.) is confined to the Southern Ocean, where many very distinct species are found, some of which are of large size, having brilliant crim- son or rose-red fronds from a quarter to half an inch in breadth, and elegantly pectinato-pinnate. To all, the alternate, or secund, acute ramuli are common ; the only variation being that in some they are deltoid, in others subulate, and in some secund in pairs, in others (as in our P. coccineum) secund in fours. In one re- markable one, P. Hookeri, Harv., a native of Kerguelen's Land, the branches bear, in addition to the subulate ramuli, occasional expanded, leaf-like processes. Fig. 1. PlocaMIUM COCCINECM : — natural she. Z. Portion of a branch. 3. Branchlet with a tubercle. 4. Tubercle. 5. Spores from the same. 6. Branchlet with stichidia. 7. A stichidium. 8. Tetraspores, transversely parted. - - ■ Ser. MelanospbbmEjB. Fam - Laminariea. Plate XLV. LAMINARIA FASCIA, Ag. Gen. Char. Frond stipitate, coriaceous or membranaceous, flat, undivided or irregularly cleft, ribless. Fructification ; cloudy spots of spores, imbedded in the thickened substance of some part of the frond. Laminaria (Lamour.) — from lamina, a thin plate, in allusion to the flat frond. Laxbiaxia fascia, Ag.; stem very short, setaceous, gradually expanding into a 'membranaceous, broadly-oblong, wedge-shaped, lanceolate, or linear frond. Laminaria fascia, Ag. Syn. p. xix. Ag. Sp. Alg. vol. i. p. 1 22. Syst. p. 273. Wyatt. Alg. Danm. no. 157. Hare. Man. p. 25. E. But. Suppl. t. 8845. Hook.JU. Fl. Ant. ined. End!. 3rd Suppl. p. 27. Laminaria debilis, Ag. Spec. vol. i. p. 120. Syst. p. 273. Grev. Crypt t. 277. Greo. Alg. Brit. p. 35. t. v. Hook. Br. Fl. vol. ii. p. 272. Hon. Man. p. 25. Endl. 3rd Suppl. p. 27. Laminaria cimeata, Su/ir. Laminaria papyrina, Bory. in Diet. Class d'Hist. Xat. vol ix. p. 189. Frcus fascia, Fl. Dan. t. 76S. Turn. Syn. vol. i. p. 186. Roth. Cat. Bot. vol. ii. p. 161. Hab. On sand-covered submarine rocks and stones in the sea, near low- water mark. Annual. Summer. North of Ireland, Mr. II. Brown, {Turner). Carrickfergus, Mr. Templeton. "Western Islands of Scotland, Mr. Chalmers. Larne, Dr. Drummond. Antrim coast, Mr. 1). Moore. Sidmouth and Torquay, Mrs. Griffiths. Mounts Bay and Salcombe, Mr. Balfs. Malahide, Mr. Mc'Calla. Saltcoats, Her. I). Landsborough. Geogr. Distr. Atlantic shores of Europe from Norway to Spain. Mediterranean Sea, C. Agardh. Falkland Islands, Lyall. Descr. Root a small disc. Stem as thick as hog's bristle, one to four lines in length, cylindrical at the base, compressed in its upper half, and gradually widening into the euneate base of the frond. Frond very variable in form, two to twelve inches long, and from a quarter of an inch to an inch and a half, or two inches, in breadth, sometimes abruptly euneate at base, sometimes much attenuated, either lanceolate, oblong or linear, or oblong-ovate ; in some cases remarkably obtuse, in others tapering to a more or less acute point, or rarely somewhat lobed at the apes, waved or flat at the margin, membranaceous, smooth, rather glossy. Colour varying from a greenish to a brownish olive, sometimes bright, sometimes very dingy. Fruit unknown. Cellules of the interior of the frond narrow-oblong, twelve-sided, pellucid; thosr of the surface very minute, arranged in areoli, four cellules in each areolns. The first notice of this species occurs in the 'Flora Danica,' in which work a figure is given which coincides in most characters with the narrower and browner of our figures, and on which is grounded the idea of the Laminaria fascia of Agardh, and succeeding authors. In Greville's ' Scottish Crypt. Flora ' ano- ther figure, resembling our broadest form, is represented under the name of Laminaria debilis, a name first proposed by Agardh for specimens sent to him from the coast of Spain. At first sight these forms appear to be abundantly distinct, the long strap-shape of one contrasting with the broadly ovate form of the other. But the slight importance to be attached to such varia- tions becomes at once evident to any observer who collects the plant in any quantity, on its native rock, and to whom specimens ranging from the broadest to the narrowest, occur in the same locality. From a very extensive suite of specimens from several parts of the coast, and of all shapes and sizes I have selected a few for illustration, in which a gradation of form is well shewn from the broad, abruptly stipitate L. debilis to the ribbon-like L. fascia. In uniting these under one specific head, I, of course, preserve the trivial name which was first proposed. Specimens gathered at the Falkland Islands, by Dr. Lyall, are identical with some of the British varieties ; and with the L. cuneata, of Suhr, which is obviously a transition plant, having a broadish frond, with a long cuneate base. Fig. 1. Laminaria fascia, different varieties: — natural size. 2. Part of the frond : — magnified, to shew the surface cellules. 3. Section of the same, showing the internal structure. \/ 17 Ser. Rhodospermk.k. Fam. Ceramiea. Plate XLVI. SPYEIDIA FILAMENTOSA, Harv. Gen. Char. Frond filiform, cylindrical, much branched, traversed by a wide articulated tube, whose walls are composed of small, angular cells; ramuli setiform, simple, jointed. Fructification of two kinds on distinct individuals ; 1, external fetra.yores, with colourless borders, attached to the ramidi ; 2, stalked, gelatinous, lobed receptacles (fa- ve/lce), involucred by short ramuli, and containing two or three dis- tinct masses of roundish spores. Spyeidia {Harv.) — from vkos, a seaweed. Fucus serratus ; frond plane, dichotomous, mid-ribbed, serrated, without air-vessels ; receptacles flat, terminating the branches, serrated. Fucus serratus, Linn. Sp. PL p. 1626. Fl. Lap. p. 365. Fl. Suec. p. 430. Huds. Fl. Any. p. 576. Light/. FL Scot. vol. ii. p. 902. Stack. Mr. Frit. p. 2. 1. 1. Turn. Syu. vol. i. p. 110. Hist. t. 90. E. Bot. 1. 1221. Lyngb. Hyd. p. 5. t. 1. Ag. Sp. dig. VoLi. p. 95; Syst. p. 278. Hook FL Scot. part 2. p. 95. Grev. FL Fdin. p. 284. Alg. Brit. p. 15. Hook. Br. FL vol. ii. p. 267. Harv. in Mack. FL Hib. part 3. p. 169. Wyatt, Alg. Damn. no. 2. Endl. 3. %>pZ. p. 29. Kiltz. Phyc. Gen. p. 352. Hab. On rocky sea shores, clothing the rocks at half-tide level. Perennial. Winter and Spring. Very common. Geogr. Distr. Atlantic coasts of Europe from Norway to Spain. Baltic Sea. Greenland, Lyngb. Coast of Piedmont, Allioni (doubtful). Descr. Foot a hard, conical disc. Frond from two to six feet long, and from half an inch to two inches in breadth, linear, traversed by a strong, thick mid-rib, regularly dichotomous, the margin sharply serrated, or occasionally laciniated. Mid-rib thickened at the forking. Vesicles none. Receptacles flat, terminating the branches, of which they are merely prolongations, slightly altered in structure, and containing numerous immersed conceptacles communicating with external pores, These conceptacles are spherical, hollow, and seem to be formed by an inflexion of the periphery of the frond. In some individuals they produce from all parts of then- inner surface, nume- rous obovate spores, which finally separate into eight distinct spondes, and are surrounded by filamentous processes. In other individuals the place of the spores is occupied by tufts of much-branched, jointed filaments, which produce an abundance of elliptical cellules, filled with numerous, bright- orange, vivaceous corpuscles or zoospores, which eventually issue from then- cases and swim about, with a rapid motion, resembling the voluntary move- ment of animalcules. These cellules are called antheridia, and then- con- tained zoospores supposed to fulfil the office of pollen. Thev are never found on the same plant as the spores, the species being strictly 'dioecious. Fucus serratus abounds on all the Atlantic shores of Europe, and probably extends to the eastern shores of America, but is not found, according to J. Agardh, in the Mediterranean Sea, although i. mentioned by Allioni. It does not appear to extend to the Pacific, nor to be found in the Southern Ocean. It presents some varieties, chiefly distinguished by the greater or less breadth of the frond, and the depth of the serratures. I have chosen one of the most common states for illustration. In the variety integer rim us of Turner, the marginal serratures are very shallow, and sometimes obsolete, but always sufficiently marked to prevent the species being mistaken. In his variety latifolius, the upper branches are very much wider than the lower, sometimes more than two inches broad, and remarkably rounded, not unlike the webbed feet of some waterfowl ; and in Greville's variety laciniatus, the serratures are very deeply cut, " and cleft or laciniate." Messrs. Decaisne and Thuret, who first discovered the zoospores above described, of which they have given a most interesting account in the ' Annales des Sciences Naturelles ", divide the Agardhian genus Fucus into several genera, of which F. serratus, F. nodosus, F. canulicukdus, and F. tuberculatm respectively are the types, and which they distinguish chiefly by the spores containing eight, four, two, or one sporules ; a minute character which accompanies some differences in natural habit, and might be resorted to were the genus Fucus of great extent. But in so small a genus it appears scarcely necessary to burden the science with so many new names. To observe the zoospores in motion, fresh specimens, collected in winter or early spring, having orange-coloured receptacles, should be removed from the water, and left to dry partially. As the surface dries, there will exude from the pores of the re- ceptacle, drops of a thick, orange-coloured liquid, which, on being placed under a microscope and moistened with salt water, will be found to be composed of innumerable antheridia, from which will issue troops of zoospores, which, the moment of their libera- tion, commence those strange animal motions which have so much puzzled philosophers to reconcile with vegetable life. Fig. 1. Fucus serkatus : — natural size. 2. Transverse section of the receptacle, shoving two conceptacles. 3. Spores from the same. 4. A. duster of anthe- ridia . 5 . A a antheridium containing zoospores, some of which have escaped : — all magnified. YLVfll Ser. Rhodosperme.e. Fam. RAodomelea. Plate XLVIII. BOSTRYCHIA SCORPIOIDES, Mont. Gen. Char. Frond dull purple, filiform, much branched, inarticulate, dotted; traversed bj a jointed tube surrounded by one or more con- centric layers of oblong, coloured cells, which are gradually shorter towards the circumference; the surface cells quadrate. Fructification of two kinds, on distinct individuals; 1, "lateral capsules" (cera- midia), Both. -2, tetiraspores, contained in terminal, lanceolate pods. BOSTRYCHIA (Mont.), — from p6ESCR. Boot a small disc. Stem G-1S inches long, as thick as hog's bristle, cylindrical, smooth, perfectly simple, furnished throughout its length with numerous lateral branches, at distances of from one to four lines asunder. Branches three to six inches long, half the diameter of the stem, gradually tapering to a fine point, quite simple, like the, stem, the whole margined throughout with receptacles. The receptacles are at first sessile and wart- like, gradually they become stalked, tin stalk varying, at different ages, and in different specimens, from a quarter of a line to nearly two lines m length. Thej are of an oblong-elliptical, or. finally, spindle form, and ii crowned with a pencil of delicate byssoid, simple, jointed fibres a quarter of an inch in length, and finally deciduous. Their struct sists in a slender cellular axis, round which jointed, hori- zontal filaments are whorled. To I nts the narrow obovate spores are attached. Substance cartilaginous, tender, becoming more rigid in the Stem. The structure ir- cellular, tin- cells of the centre and those near the ng minute; the intermedial '.lax, and po ■ when fresh ire, drying to a yellow green, and becoming brown in age. When young the plant adheres closely to paper in drying Sporochnus pedunculatus, though found in several widely sepa- rated places on the English and Irish coasts, is nowhere very common, and thus recommends itself by its rarity, as well as its beauty, to the collector. Few objects, indeed, are more attractive to the eve of a botanist than a fine frond of this species, as it waves its feathery branches in the water ; but were the use of the dredge more general with algologists, this, and many other deep water plants, would, probably cease to be regarded as of rare occurrence; and Ave should be better acquainted with their habits, and the exact localities which they frequent. Most of the specimens now collected, are washed up by the tide, frequently in an imperfect, or decaying condition; or picked out of fisher- men's nets, in the meshes of which they get entangled and torn. If raised by the dredge they would not only be found more per- fect, but in far greater plenty. Hudson was the first to describe this species, in his 'Flora Anglica.' It is of rare occurrence on the Continent, and has not been found out of Europe. Agardh regards as a distinct species, a Spanish plant which closely resembles it, and which differs chiefly from our S. pedunculatus, in the form of the receptacles. It is not improbable that this also may be found on our southern shores. The genus Sporochnus, as now restricted, contains four or five species, none of which, except the present, have yet been found in Britain. They are natives of the warmer parts of the Tem- perate /ones of both hemispheres, where they inhabit deep, quiel bays. Those of New Holland are of a much larger size than our British species, but have a very similar habit. Pig. 1. Sporochnus pedunculatus : — the natural size. 2. Receptacles ol different ages. 3, A filament from the same. i. A transverse section of tin 1 stem: — all magnified. BIRMINGHAM Jin/. /J'//. Ser.BaoDOSMEME*. V*m. Gloiocladiea. Plate LVII. GLOIOSIPHONIA CAPILLARS, Car,. Gen. Char. Frond cylindrical, tubular, gelatinous ; the periphery composed oi a thin stratum of longitudinal, interlaced fibres, clothed externally with short, horizontal, branched, moniliform filaments. Fructification spherical masses of spores {favellidia), immersed in the moniliform filaments, to whose bases they are attached. Gloiosiphonia {(Jarm.) — from yWor, moid, and o-tyov, a tube. ( i loiosiphonia capillars, Gloiosiphonia capillaris, Car m . Alg. Appin. MS. Berk. Gl.ofBr Ala t 17 % ffiT '" ' ** flB ' P8rt 3 " P ' 187 ' Han - Mm - P 49 " ***& Mesogloia capillaris, Ag. Syst. p. 51. Han. m Hook. Br. M. vol. ii. p. 386. Gigartina capillaris, Lanwiir. Ess. p. Gigartina lubrica, Lijmjb. Hi/d. Dan. p. 45. t. 12 (Sec. Ag.). Fucus papillaris, Huds. M. Ang. p. 591. With. vol. iv. p. 115 Turn Sun vol. n. p. 370. Hist, t. 31. E. Bot. t. 2191. ' ' y Hab. On submarine rocks, growing in tide-pools, near low-water mark ■ frequently cast on shore from deeper water. Annual. Summer At Sheerness, and m Devonshire and Cornwall, Hudson. Scarborough Air 1.1 nod-land. Anglesea, Rev. II. Barks. Sidmouth and Mead- foot, Mrs. Griffith. Bantry Bay, Miss Hutckms. Appin, Captain CarmcAael. Glenarm, Zb-. Dnmmond. Boundstoue Bay bV )/,•' Calla Howth and Balbriggan, .1/;™ GWw. Saltcoats, on shale Km. D. Landslorongh. Arran, L. Landsborough, Jm. Mount's Bay' Jp. A«//,y. Falmouth, J//.M BWew. Jersey, Miss White and J//** (WW. Gf.ogk. Distk. Atlantic shores of Europe, from Norway to Spain. Ih.M -is. Soot a small disc. Fronds, several from the same base, from three to toelye inches ill length, cylindrical, varying m diameter from a quarter of a line to a line and upwards, rising with an undivided stem which is thickest in the middle and gradually tapers to either end, being reduced at its apex to a capillary fineness. The stem is generally bare of branches for a short space above its base, varying in different specimens from half an inch to an inch and a half. From this point to its summit it is closely clothed with lateral branches, several times compounded until the ultimate ramuli are reduced to small setaceous processes. The loner branches are longest the upper gradually diminishing in length and in composition, and the outline | consequently ovate-oblong. All are more or less quadrifarious rivine a bushy character to the frond, and all taper at the has,- and are attenuated* the apex. They are ether opposite or alternate. The^-W is tubular, either empty or filled with a watery gelatine. In walls are composed of doseli interwoven, branching, longitudinal fibres, through whose joints runs a very narrow, coloured bag, and they are clothed external y with a pd of 1 ,rt d ho omous, mombform coloured filaments, winch fonn the coat of Z frond Lui»i sphem-al masses of closely compacted, mmute on'bunda.nh seat., red among the filaments of the periphery. Cbfo«r ,.,,,;!■ rl *j -crimson. Oibta« tender, slippery and gelatinous, very closely adhering to paper in drying. A highly beautiful plant, nearly related in affinity to the genus Budremaia, but, according to the views of the late Captain Carmichael of Appin, forming the type of a separate genus, winch differs from Dudresnaia chiefly in having a tubidar axis. The structure, as seen by the microscope, is very beautiful, and such that it is impossible to do it justice in drawing, the extreme lubricity and transparency of the parts being lost m a lithograph. The whole plant is very tender, and invested with a gelatinous pellicle and each filament of which it is composed stands sepa- rated from its neighbour by a similar coating. These characters are lost hi our plate, which is, in other respects, a faithful portrait, Gkiosiphonia cqpillaris is one of those species which is rather uncertain in its appearance, being found in some seasons m con- siderable plenty, and not occurring again, sometimes, for several years. The causes of such temporary disappearances of certain sea plants are very obscure, and will probably long remain so. The most probable seem to be changes which may take place in the bottom of the sea by the shifting of sand or gravel, an over- flowing of which would smother the vegetation, and would not afford sufficient stability for the roots of a new crop. In many instances this cause no doubt prevails. In some others, the difference of temperature, small as this is, of different seasons, appears to be the chief, or the only, cause of failure. 1 Gloiosiphonia caphxabis:— natural sine. 2. A small branchlet. 8 Transverse section of the tubular frond. I, A segment oi the same, enlarged. 5. A longitudinal section of the frond -.—all uort or less highly magnified. r/,,t> i nn Ser. Chloeospeilme e. Fain. Oscillal<>ri<;r. Plate LVIIl. A. CALOTHRIX FASCICULATA, Ag. (ii\. Char, Filaments destitute of a mucous layer, erect, tufted, or aggre- gated, fixed at the base, somewhat rigid, not oscillating. Tube con- tinuous ; endochrome green, densely simulated, at length dissolving into lenticular sporidia. Calothrix {Ag.) — from koaAs, beautiful, and 6p\£, a hair. Calothrix fasciculata ; stratum velvetty, dark green, of indefinite extent; filaments very straight, subulate, muck attenuated, fasciculately pseudo- branched. Calothrix fasciculata, Ag. Syst. p. 71 (exel. *'/"■)■ Han. in Hook. Br. Fl. vol. ii. p. 368. Han-, in Mack. Fl. Hii. part 3. p. 237. Han. Man. p. 158. Hab. Spreading over the surface of marine rocks, about half-tide level ; probablv common. Annual? Found at all seasons. Miltown Malbay, W.ll.'H. Geogr. Distr. Baltic Sea. British Islands. Descr. Stratum of indefinite extent, from a few inches to several feet in diameter, of a dark, shining green colour. Filaments from two to three lines in height, tufted, erect, straight, tapering to a long, setaceous, pellucid point. In an early stage of growth they are quite simple, and sometimes remain so, but more generally they are furnished with from two to six or more, erect, closely pressed pseudo-branches. Stria or annuti strongly marked, and closely set. Colour under the microscope, a deep, glaucous green. This is nearly related to 0. scopvlorum, which I have therefore figured on the same plate ; and I am by no means sure that it should not be considered as merely a more developed form of that plant, the differences being occasioned by its growing at a greater depth, and in places where it is more constantly sub- merged. The filaments are taller, straighter, more acuminate', and of a deeper green than in C. scopuhrum, and very frequently are furnished with tufts of accessory branches, but this is a character of minor importance. The genus Calothrix, as defined by Agardh, contains many species, the majority of which, as of the OsciUatoriea in general, are found in fresh water. By Kutzing this genus has been broken up into several, and formed into a distinct family, an innovation of very questionable character, productive of a host of new synonynies. A. Fig. 1. Calothrix fasciculata. Portion of the stratum: — the natural size. 2. A tuft of filaments. 3. Apex of a filament *— magnified. Plate LVIII. B. CALOTHRIX SCOPULORUM, a 9 . Calotitrix scopulorwn ; stratum velvetty, dirty green, of indefinite extent ; filaments' flexuous, subulate, sub-attenuated, simple. Caloturix scopulorum, Ag. Syst. p. 70. Han. in Hook. Br. Fl. vol. ii. p. 368. Han. in Mack. Fl. Hib. part 3. p. 237. Han. Man. p. 157. Oscillatoria scopulorum, Ay.Syn. p. 111. Hook. Fl. Scot, part 2. p. 79. Grev. Fl. Edin. p. 30-1. Conferva seopulonmi, JFeb.etMohr,Rek. p. 195. t, 3. f. a, b. Roth. Cat. Bol. vol. iii. p. 191. Dillw. Conf. Introd. p. 39. Suppl. t, A. E. Bot. t. 2171. Hab. On marine rocks, near high water mark. Common. Geogr. Distr. Shores of Europe ; and probably dispersed throughout the tem- perate zones. Descr. Stratum of indefinite extent, dark, dirty green, slippery. Filaments a line in height, flexuous, often very much curled, subulate, tapering to a more or less acute point, crowded, tufted, the tufts glued together at the base by a slimy matter, simple. Stria sometimes indistinct ; sometimes well-defined and very close. Colour, under the microscope, a dull, yellowish green. This forms slimy patches, very treacherous to unwary feet, on the surface of rocks near high-water mark, often growing in places where it is only wet by the splashing of the sea, or only covered at spring tides, and where it is much within the influence of rain. It is found on all our shores, on rocks of every geo- logical character indifferently, and is probably to be met with in similar situations all over the world. It was first detected in Sweden, by Weber and Mohr, and introduced to the notice of British botanists by Mr. Dillwyn. B. Fig. 1. Calothrix scopulorum. Portion of the stratum .—the natural size. 2. A tuft of filaments. 3. Apex of a filament : — both magnified. /'/.,/, /,/.!'. Ser. Rhodospkrmkb. F:.m. Gasterocarpea. Plate LIX. DUMONTIA FILIFORMIS, Grev. Gen. Char. />aipa a sphere ox globe, and k6kkos, Jhiit. SphjErococcus coronopifolim ; frond very much branched, branches alter- nate or subdieliotomous, fan-shaped, multifid, ending in acute laciniaj, fringed with cilia ; tubercles immersed in the cilia. SpHjEROCOCCCS coronopifolius, Ag. Sp. Alg. vol. i. p. 291. Ag. Sgst. p. 229. G-rev. Alg. Brit. p. 138. 1. 15. Hook. Br. Fl. vol. ii. p. 304. Han. in Mack. M. JEK6. part. 3. p. 203. Wyatt,Alg.Danm. n. 122. Harv.Man. p. 79. /. Ag. Alg. Medit. p. 154. Endl. 3rd Suppl. p. 52. Gelidium coronopifoliimi, Lamour. Ess. p. 41. Rhynchococcus coronopifolius, Kiitz. Phyc. Gen. p. 403. t. 61. f. 1. Fucus coronopifolius, Good, et Jl'oodw. in Linn. Trans, vol. iii. p. 185. Stack. Ner. Brit. p. 82. t. 14. Turn. Syn. vol. ii. p. 288. Turn. Hist. t. 122. E. Bot. t. 1478. Eqier, Ie. p. 60. 1. 138. Lamour. Dis. t. 33. Fucus coronopi facie, Bail Syn. p. 45. n. 23. Fucus cartilaginous, Hnds. Fl. Aug. p. 580 {not of Linn.). Desf. Fl. Atlant. p. 425. Hab. On rocky sea shores, at extreme low-water mark, and at a greater depth ; mostly cast on shore after a gale. Perennial. Summer and Autumn. Erecpient on the southern shores of England, and southern and western shores of Ireland. Belfast Bay, Mr. Templeton. Larue, Dr. Drummoud. Very rare in Scotland ; Bute Dr. Greville. Ardrossan, Kilbride, and Arran, Rev. D. Landsborougli. Jersey, Miss Turner and Miss White. Geogr. Distr. Atlantic shores of Europe. Mediterranean Sea. I)escr. Root a flattish disc. Fronds from six to twelve or even eighteen inches in length, from two to four lines in width, very much branched, distichous; the main stems compressed, thickened and two-edged below, becoming thinner and flatter in their upper parts, irregularly divided in a manner between dichotomous and alternate, the upper branches once or twice forked, gradually narrower, and ending in fan-shaped many-cleft lesser branches. LacinuB tapering to an acute point, their margins, and sometimes those of the older parts of the frond, fringed with slender cilia from half a line to a line in length, simple, acute, and spreading, in some of which tubercles are imbedded. Tubercles spherical, imbedded in the cilia below the apex, which is slightly produced beyond them, forming an oblique mucro ; their walls rery thick, the inner portion formed of largish, polygonal cells, the outer of a stratum of closely packed vertical filaments. A very dense, broad, more or less clearly defined, sometimes obsolete mid-rib runs through the substance of the frond, and faint lateral, oblique veins proceed from it ; both formed of elongated, cylindrical cellules, disposed in longitudinal fibres. The cells composing the middle stratum of the frond are polygonal, gradually becoming smaller outwards ; and those of the periphery are very minute, 'and arranged in closely packed, vertical filaments. Colour a tine scarlet pink, dark in the main branches. Substance cartilaginous, imperfectly adhering to paper in drying. In reforming the genus Sp/iarococcus, which, in the work of Agardh included a large number of species now dispersed into many genera, and many of which had little in common with each other except the spherical fruit, Dr. Greville confined the amended genus to the S. coronopifoliiis and to S. crinitus, Gin. The first of these, being the best known, is to be considered the type. Its structure is peculiar ; under a pocket lens may be observed running through the branches the faint appearance of a mid-rib, connected with the margin by oblique lateral veins, both of which were first observed by Mr. Sowerby. By making a transverse section, and applying a more powerful glass, this venation is seen to be caused by an internal rib, composed of denser and more elongated cells than the rest of the frond ; and if the internal structure of the frond affords, in the FlorideBe, the surest generic characters, the presence of such a rib ought to be essential to the genus. Judged by this rule, my S. aiistralis (Harv. in Hook. Lond. Journ. vol. hi. p. 445), notwithstanding that outwardly it bears a close resemblance to S. coronopifoliiis, must be removed from the genus, its internal structure being extremely lax, and more like that of Gracilaria, a group which, if allowed to retain all the species which seem disposed to drop into it, will soon be as anomalous as Spharococcus was formerly. S. eoronqpi/olius appears to have been first noticed by Ray, in whose ' Synopsis ' it is described. It is said to be unknown on the eastern coast of England. In Ireland it is more common, and is found at both sides of the island. In Scotland it is extremely rare. Pig. 1. Simi.v.udcoccUS COKONOPIFOLIUS : — natural si:e. 2. Portion of a branchlet. 3. Section of a tubercle. 4. Spores. 5. Cross section of a main branch, in its lower part. (J. Longitudinal section of the same : — all more or less //i;//i/i/ magnified. Ser. Cui.okosi'ekme.e. Fam. Oscillatoriea. Plate LXII. LYNGBYA MAJUSCULA, Haw. Gen. Char. Filaments destitute of a mucous layer, free, flexible, elongated, decumbent, not oscillating. Tube continuous ; endochrome green or purple, densely uimulated, and finally separating into lenticular dia. IiTOGBTA (Aff.) in honour of // have belonged to a sea nymph, the dark green hue is not so inappropriate. Lyngbya majtiscula was discovered by Miss Hill, early in the present century, and first described by Dillwyn, in bis work on the British Confervae. It is well known to British naturalists, and has been found in several localities on our shores ; but on the Continent it appears to have escaped notice. Agardh quotes Dillwyn's figure under his L. crispa, a plant, which, to judge by a specimen communicated by Agardh himself to Sir Wm. J. Booker, is a very different plant, having a verdigris-green colour, and being thrice as slender. As a genus, Lyngbya is intermediate between Oscilkitoria and Calothrix. From the first it differs, by having long, flexible fila- ments, destitute of oscillatory motion ; and from the latter, by its stratified habit. There are several species, the most common of which is a terrestrial one [L. muralis), which forms a silky stratum of a brilliant green colom on the surface of damp ground, and abounds everywhere, and at all seasons. The major part of the species, are, however, marine ; and, besides the pre- sent individual, three others are found on our coasts, and will be figured in a future number. The genus Bat/gin has many points in common with Lyngbya, and is even united to it by Mr. Hassall, but if these genera are to be combined, Bangia, being the older name, must be adopted. Fig. 1. Lyngbya majuscula; Part of a stratum: — natural size. 2. Apices of two filaments : — highly magnified,. Tla2 Ser. Rhodospermr.e. Fain. Spongiocarpece. Plate LXIII. CHONDRUS CRISPUS, L yng b. Gen. Char. Frond cartilaginous, nerveless, compressed or flat, flabelliform, dichotomously cleft ; formed internally of tliree strata ; the inner, of densely packed, longitudinal fibres ; the medial, of small, roundish cells; the. outer, of vertical, coloured, moniliform filaments. Fructifi- cation; 1, prominent tubercles [nemathecia) composed of radiating filaments, whose lower articulations are at length dissolved into spores (?); 2, tetraspores collected into sori, immersed in the substance of the frond. Chondrus [Stack) — from xoi/fyos, cartilage. Chondetjs crispus ; frond stipitate, thickish, cartilaginous, flat or curled, segments wedge-shaped, very variable in breadth; apices truncate, subemarginate or cloven ; axils obtuse ; sori elliptical or oblong, con- cave on one side. Chondrus crispus, Lyngb. Hyd. Ban. p. 15. t. 5. A. B. Grev. Alg. Brit. p. 129. 1. 15. Hook. Br. Ft. vol. ii. p. 302. Harv. in Mack. Ft. Eib. part 3. p. 201. Wyatt, Alg. Damn. no. 118 and 119. Endl. 3rd Suppl. p. 39. Harv. Man. p. 77. Kiitz. Phyc. Gen. p. 398. t. 73. hi. Chondrus polymorphus, Lamx. Ess. p. 39. Chondrus incurvatus, Kiitz. Phyc. Gen. p. 399. t. 73. ii. Chondrus celticus, Kiitz. I. c. Sph^rococcus crispus, Ag. Bp. Alg. vol. i. p. 256. Syst. p. 219. Grev. Ft. Edin. p. 294. Sprang. Syst. Veg. vol. iv. p. 335. Fucus crispus, Linn. Mant. p. 134. Syst. Nat. vol. ii. p. 718. With. vol. iv. p. 106. Stack. Ner. Brit. p. 63. t. 12. Turn. Syst. vol. ii. p. 226. Hist. t. 216, 217. Clem. Ess. -p. 313. Wahl.Fl.Lapp.y.VZI. E. Bot. t. 2285. Fucus ceranoides, Gm. Hist. Ficc. p. 115. t. 7. f. 1 . (Excl. syn. Linn.). Ends. Fl. Any. p. 582. Liglitf. Fl. Scot. p. 913. Roth, Fl. Germ. vol. hi. p. 450. Esper, Lc. Fuc. vol. i. p. 143. t. 98. f. 1, 2, 3. Fucus membranifolius, With. vol. iv. p. 106 (not of Gooden. and Woodw.). Fucus polymorphus, Lamx. Hiss. p. 1. (excluding the fourth series). Fucus stellatus, Stack. Ner. Brit. p. 53. t. 12. Fucus lacerus, Stack. 1. c. p. 50. t. 11. Fucus crispatus, Fl. Ban. t. 826. Fucus fihformis. Huds. Fl. Ang. p. 585. Fucus patens, Gooden. and Woodw. in Linn. Trans, vol. iii. p. 173. Hab. On rocky sea shores, extending from three quarters tide level to low water mark, and beyond it. Perennial. Spring and Summer. Very abundant on the shores of the British Islands. Geogr. Distr. Shores of Europe from North Cape to Gibraltar. Not found in the Mediterranean ? Eastern shores of North America. BIRMINGHAM Descr. tfod, a flattened disc. Fronds tufted, many springing from the same Le from one to ten or twelve inches in height, rising with a subcylmdrical, slender stem, which soon becomes flattened, and at an mch or more trom »hc root widens into the cuneate base of a fan-shaped many parted frond. The segments vary much in width, and in the amount ot their furcation. Sometimes they are not more than a Hue wide, nearly perfectly linear, flat, and very many' times dichotomous; sometimes they are from one to four inches in breadth, very much curled, and broadly cuneate, overlapping i ad other Sometimes the margin is quite entire and even ; in other specimens it is lobed, or proliferous, or fringed with leafy processes. The apices are more or less truncate, emarginate or bifid; and the axils, especially of the broad varieties, are very blunt. The colour is extremely variable ranging from a yellowish green to a livid purple, or a purplish-brown. Fruc^iatton ; tetraspores collected in dense sori, contained in oval or oblong cavities irre- gularly scattered through the lamina of the frond, and usually concave on one side. Substance cartilaginous, becoming soft, and finally dissolving into a gelatine in fresh water. So variable is the present species in appearance, under different circumstances, that it is quite impossible to enumerate the many forms it puts on, and were we to attempt to figure even the prin- cipal varieties, the figures would fill many plates. Turner has ten varieties ; and Lamonroux figures thirty-five. I prefer repre- senting two of the most opposite forms. My upper figure shows the state of the plant when growing near low water mark, in situations exposed to the Ml dash of the open sea. The lower is from an estuary where a fresh water stream mixes with the sea, and brings down much mud and sand. In this situation the Chondrus attains even a greater size, and is frequently very much lobed and fringed. This plant is the Carrigeen. or Irish moss of the shops, and is used in place of isinglass in the preparation of blancmanges, and jellies, the frond boiling down to a clear, tasteless gelatine. A few years ago it was a fashionable remedy in consumptive cases, and the collection and preparation of it for market afforded a small revenue to the industrious peasantry of the West Coast of Ireland, where it first came into use. The price at one time was as high as U M. per lb., but the fashion has gone out, and the plant almost ceased to be collected. 1 Chondrus cwsptjs, a narrow variety, 2. The same, a broad ^variety : ^natural -si.-,: 3. Transverse section of the frond. 4. Longitudinal sec- tion— both magnified. 5. Specimen producing sori -.— natural sue. 6. Transverse section of the frond, and of two sori. 7. Tetraspores from the sorus : — both magnified. Ser. Melanosperme.e. Pam. 8porochnoidea. Plate LXIV. ARTHROCLADIA VILLOSA, Duty. Geht. Char. Frond filiform, cellular, with an articulated, tubular axis, nodose; the nodes producing whorls of delicate, jointed filaments. Fructification; pedicellate, moniliform pods, borne on the filaments, and containing, at maturity, a string of elliptical spores. Arthrocladia (FuLy) — from apBpov, & joint, and kXuSos, a branch. Arthrocladia villosa. Autiiroclapia villosa. Bubi/, Mem. Ceram. p. 18 (1S32). /. Ag. Alg. MedU. p. 43. Endl. Zrd Suppl. p. 25. Kiit:. P/tgc. Gen. p. 344. Elaionema villosum, Berk. Glean, p. 49. 1. 19. f. 3 (1833). Han. Mm. p. 28. Sporochnus villosus, Ag. Sp. Alg. vol. i. p. 155. Ag. Syst. p. 260. Grev. Alg. Brit, p. 42. Hook. Br. Fl. vol. ii. p. 274. Tf'gatt, Alg. Damn. no. 105. Hare, in Murk. Fl. Hid. part 3. p. 173. Conferva villosa, Huh. Fl. Ang. p. 603. With. vol. iv. p. 141. E.Bot. t. 546. Dillw. Con/, t. 37. Both. Cat. Bot. vol. iii. p. 314. Hab. On submarine rocks, shells, &&, and on Zostera, in four or five fathoms water, rare Annual. Summer and Autumn. Southern coasts of England, not uncommon. Yarmouth, Turner. Anglesea, Sev. II. Fades. Frith of Forth, Mr. Basell. Ardthur, Copt. Cdr- michael. 'Wicklow, //". H. II. Malalride, and Carrickfergus, Mr. Mc'Calla. Jersey, Miss Wliite and Miss Turner. Geogr. Distr. Atlantic shores of Europe. Baltic sea. Mediterranean sea, (very rare). Descr. Root, a minute disc. Fronds several from the same base, from sis inches to nearly three feet in length, very slender, once, twice, or thrice pinnated ; the pinna; distant, opposite, or rarely alternate, patent, simple or again pinnated with similar, simple pinnules ; all the branches furnished at intervals of from half a line to a line, with minute, knob-like swellings which produce whorls of very delicate, byssoid, repeatedly pinnate jointed fila- ments of a pale green colour. The substance of the frond is traversed by a wide tube, about one third of the width, which is divided by transverse septa into joints or chambers, whose length is rather less than their breadth, and four or five of which interpose between every whorl of filaments. This tube is surrounded by a row of large cellules, and these again bv several rows of smaller ones, which gradually diminish to the circumference. The substance when quite fresh is cartilaginous, but it soon becomes flaccid. Fructification ; minute, articidated, lanceolate pods (ttichidia) borne alone the sides of the whorled filaments ; at first short, finally much lengthened, moniliform, and containing, at maturity, in each joint, an oval more of an olive colour, which at length bursts through the membrane and falls awav. In drying it adheres firmly to paper. This elegant plant, which was formerly included in the genus Spwochmts, was, nearly at the same time, by M. Duby in France, and by the Rev.M. J.Berkeley in this country, proposed as the type of a distinct genus. M. Duby's name, having the priority of a few months, is here adopted. Of the propriety of constituting a new genus in this instance, there can be no question, both the structure of the frond, and the nature of the fructification being very unlike that of the Sjiorochiii. There is, indeed, a much closer connection with Desmarestia, both in habit and in struc- ture, and it is very probable that the fruit of Desmarestia may prove to be analogous to that of the present genus. At a first glance the difference in the structure of the frond between Des- marestia and Arthrocladia appears considerable, but a closer ex- amination removes much of the dissimilarity. A jointed tube runs through the centre of both fronds ; in the Desmarestia, in the form of a slender filament ; in the Arthrocladia of a wide tube. The confervoid filaments are of the same nature in both genera, and the branching of the fronds identical. The great difference lies in the comparative density of Structure. Dr. Greville mentions that Mr. Hasell, the discoverer of A. villosa in Scotland, observed that " fresh specimens when spread upon paper, rendered it transparent, as if it had been touched with oil ; but in a very short time the transparency quite disap- peared." This property is not peculiar to this species, but exists also hi young specimens of Desmarestia Ugulata, and D. Aerbacea, and perhaps of others of the family, and affords another evidence of the strong natural connection of these plants. Another com- mon point of resemblance consists in their soon becoming flaccid and changing to a verdigris green colour on exposure to the atmosphere, and then causing the rapid decomposition of any other delicate Alga in contact with them. This is common to all the Sporochnoidea . Fii>cu, to hear ; in allusion to the dot-like fructification. Stii.ophora rhizodes; frond subsolid, much and irregularly branched, the branches subdichotomous, attenuated ; ramuli scattered, forked; fruc- tification densely covering the whole plant. Stilopiiora rhizodes, /. Ag. Linn, vol xv. p. 6. Midi. 3rd Suppl. p. 26. Spermatociinus rhizodes, Kid:. Plnjc. Gen. p. 335. SpouociiNUs rhizodes, Ag. Sp. Alg. vol. i. p. 156. Ag. Syst. p. 260. Spr. Syst. I'eg. vol. iv. 329. Grev. Alg. Brit. p. 43. t. 6. Hook. Br. Ft. vol. ii. p. 275. Hnrv. in Mack. Fl. Hib. part 3. p. 173. Wyatt, Alg. Lamm. no. 5. Harv. Man. p. 27 (excl. var. 0.). Chordaria rhizodes, Ag. Syn. p. 15. Lyngb. Ilyd. Ban. p. 52. t. 13. Fucus rhizodes, Turn. Hist, t 235. Conferva rhizodes, Ehr. in Herb. Conferva gracilis, Wulf. Crypt. Aquat. no. 23. Conferva verrucosa, E.Bot. t. 1688. ('f.ramium tuberculosum, Roth, Cat. Bot. vol. ii. p. 162. vol. 112. Hah. Near low water mark, growing either on rocks, or parasitically on other Algee. Annual. Summer. Southern shores of England, frequent. Common on the eastern, southern, and western shores of Ireland. Belfast Bay, and Strangford Lough, Mr. W. Thompson. Jersey, Miss II fiite and Miss Turner. Gf.ogr. Distr. Atlantic shores of Europe. Baltic Sea. Hi: sir. Boot, minute, scutate. Fronds solitary, or tufted, from six inches to two feet, or more, in length, cylindrical, filiform, much and irregularly branched, sometimes pretty regularly dichotomous, sometimes with a leading stem bent in a rlexuous or zigzag manner, and furnished with closely set, alternate branches, which arc more or less regularly dichotomous. In some specimens several of the branches are secund, and plentifully beset with short, simple, or forked ramuli ; in others the branches are bare and but little divided. In all varieties the axils are obtuse, and the apices taper to a more or less fine point . The fructification is very densely dispersed over the whole frond, giving the branches a warted or knotted aspect. The warts arc cither hemispherical or oval, and consist of radiating, beaded, clavate, simple filaments, among which obovate spores, with wide borders, and narrow, tapering bases are found fixed to the surface of the frond. In a young state the frond is quite solid, composed of roundish or subhexagonal cells, the outermost of which are gradually smaller; in age the centre becomes more or less hollow. Sui- Uance when fresh, cartilaginous, but if kept long, becoming very gelatinous and slippery, giving out in fresh water, considerable quantities of slimy matter. Colour yellowish brown, either drying to an olive, or retaining much of its original hue. Hitherto, in British works, the plant here figured has been regarded as a species of Sjjorochnus. It is now removed, ac- cording to the views of all recent continental authorities, to the THctyotea, in which family it constitutes the type of a new genus. If we compare its fructification with that of Asjjcrn- coccks, or of Ptinctaria, we shall be satisfied that its true place in the system cannot be very far apart from these genera. The difference, indeed, is more in the nature of the frond, and the general habit, than in the fructification. From the true fijpo- rochni, one of which we have figured at PI. LVI. the fructification of the present plant essentially differs, the position of the spores, their form, and the nature of the filaments that accompany them, being quite dissimilar. The var. /S. of British authors is now regarded by Professor J. Agardh as a distinct species, called by him Stilophora Lt/ngbi/ei. I have some hesitation in admitting it to the rank of a species notwithstanding its peculiar character, and the great abundance and uniformity of its production, wherever it occurs; and it has been found from the south of Ireland to the Orkneys, everywhere preserving the fistular stem, divaricated branches, and attenuated nuuuli. It is always found in deeper water than the normal form, and always in land-locked bays, and these modifying causes I have hitherto believed, produce the variations. It is, however, at least a well-marked variety, and, as such, deserving of a figure and description, both which I purpose affording it in a future number of this work. Pig. l. Stilophora rhizodes: — the natural size. 2. Part of a branch. 3. Transverse section of the same, 4. Section of a sorus. 5. Spores: — all more ur less Imjlily magnified. 8er. RHODOSPEUMJE-fE. Fain. Spongiocarpece. Plate LXXI. PEYSSONELIA DUBYI, Crouan. Gen. Char. Frond, brownish ml, depressed, rooting by the under surface, concentrically zoned, composed of several rows of cellules, disposed obliquely in filamentous scries. Fructification ; warts scattered over tlie upper surface of the frond, formed of radiating filaments, and containing oblong, cruciately divided tetraspores. Peyssonelia (Due.) —in honour of J". A. Peyssonel, an early and meritorious observer of marine plants, especially of Corallines. Peyssonelia Dubyi; frond membranaceous, orbicular or lobed, attached by the whole of its under surface. Peyssonelia Dubyi, Crouan, in An. Sc. Nat. 18-14. p. 3G8. 1. 11. B. IIab. On old shells, stones, &C, in 10-15 fathoms water. Probably com- mon on the British coasts. North of Ireland, Mr. Thompson. Bir- turbui Bay, on the Scallop bank, Mr. Me' Catla. West of Scotland, Rev. I). Landslorough. Geogb. Distr. Coast of Normandy, Crouan, (probably un all the Atlantic shores of Europe?). DESCR. From!, from half an inch to an inch and a half in diameter, at first orbi- cular, in age becoming irregularly shaped, with a lobed or wavy margin, the lobes here and there overlapping- each other, membranaceous, thin, concen- trically zoned, attached by the whole of its under surface, by means of short, slender, colourless, rooting processes, which form a laxly disposed pubescence, extending over the lower surface. A vertical section of the frond exhibits a cellular structure, the cells arranged in ascending filamentous series, of which those near the centre of the frond are nearly vertical, and become more oblique as they approach the margin. Fructification, spongy warts, scattered over the upper surface, composed of pale filaments, similar i in colour, to those that compose the frond, among which arc dis- posed vertical, elliptic-oblong tetraspores, the endroehrome of which divides at maturity, by lines crossing at right angles, into four equal parts. Colour t a dull brownish red. Substance membranaceous. The species here figured is an instance among many that might be mentioned, of one of those obscure plants which escape the attention of collectors, but which, when once pointed out, are found to be very common, and even to have been noticed and neglected by many persons, long previously to their having been found by the individual who has rescued them from oblivion by giving them a name. To win mi in such cases attaches the T merit of discovery ? Certainly to the last observer. In the present instance the palm belongs to M. Crouan, unless the P. orbicularis of Kiitzing, described a short time previously, be a s'ynonynie. Mv first acquaintance with this plant was at Roundstone, last summer, where, while dredging in Birturbui Bay, Mr. Mc' Calla called my attention to specimens which came up abundantly in the dredge, attached to broken shells, stones, &c, and informed me that he had frequently observed the plant before. On exa- mination with the microscope, I at once recognized them as belonging to Pe>/ssonelia, and not being then aware of M. Crouan's memoir, I believed that I had alit upon an undescribed species, which I proposed to call P. borealis. On communicating the supposed discovery to Mr. Thompson, he sent me a specimen dredged in Strangford Lough so long ago as 1833, and which had lain in his cabinet unnamed. And still more recently, on communicating with Mr. Berkeley, that learned Cryptogamist referred me to M. Crouan's memoir, and favoured me with an authentic specimen of the French plant, which proves to be per- fectly similar to our Irish specimens. The genus Peyssonelia was founded by Decaisne, on the F/tcr/s squammarius, Gm., a species common in the Mediterranean, of larger size, and more coriaceous texture than the present, and attached by a portion only of its lower surface. The Zonaria rubra, Grcv., in Linn. Trans, is probably the young of that spe- cies. I am only acquainted with Kiitzing's P. orbicularis by the short description given in his work, by which it appears to be very closely allied to our P. Dubyi, but to differ in having its lower surface glabrous, and closely adherent. Kg. I. Peyssonelia Dubyi, growing on a dead shell of Cytherea lincta: — the natural size. 2. A. vertical section of the frond, and of a wart. 3. Spores: — both magnified. /'/,,/, /..XXIf. /.:. Ser. Mklanospermk.e. Faro. Dicfyotea, Plate LXXII. ASPEROCOCCUS COMPRESSUS, Griff. Gen. Char. Frond, unbranched, tubular, cylindrical, or rarely compressed, continuous, membranaceous. Root naked, scutate. Fructification scattered over the whole frond, in minute distinct dots {sort), composed of roundish, prominent spores, mixed with club-shaped filaments. Asperococcus, — corruptly formed from asper, rough, and kokkos, a seed. Asperococcus compressus; frond compressed, flat, linear-lanceolate, obtuse; dots of fructification oblong. Asperococcus compressus, Griff. MSS. Hook. Br. Ft. vol. ii. p. 278. Wyatt, Jiff. Damn. no. 8. Harv. Man. p. 34. J. Jg. Jig. Medit. p. 41. Mcnegh. Jig. Hal. p. 164. t. 4. f. 1. Endl. 3rd Suppl. p. 26. Haloglossum Griffithsianum, Kutz. Phyc. Gen. p. 340. Hab. Parasitical on Algse, beyond low water mark ; usually cast on shore. Annual. Summer. Sidmouth and Torquay, Mrs. Griffiths. Mounts Bay, Mr. Ralfs. Falmouth, Miss Warren. Jersey, Miss Turner. Geogr.Distr. Southern shores of England. Mediterranean Sea. Cherbourg. Cape Finisterre. Cape of Good Hope, W. H. H. Descr. Root, a small disc. Frond, from six to eighteen inches in length, and from a quarter of an inch to an inch and a half in breadth, attenuated at the base into a setaceous stem from a quarter to half an inch long, thence nearly linear upwards for the greater portion of its length, and again fining off towards the blunt point. Some specimens are nearly lanceolate, and much narrowed at the extremity ; others are more nearly linear, and very blunt. The frond, though very much compressed, so as to be qmte flat, is in reality tubular, but the sides of the tube are closely applied together, and here and there united by slender, colourless, jointed filaments. The surface cellules of the frond are minute ; but those coating the inner face of the tube are very large, distended, and hyaline. Fructification is always abundantly produced. The sori are oblong, very densely scattered, and of larger size' than in A. Turneri. Tin- Colour varies from a pale yellowish to a full olive-green, occasionally brownish in age. The substance is tender, somewhat gelatinous, and the plant in drying, adheres perfectly to paper. An interesting plant, curiously connecting the genus Aspero- coccus and Punctaria, having a frond nearly intermediate in cha- racter between that of these genera, but possessing rather more of the structure of the former. It was discovered by Mis. Griffiths in the year 1S2S, at Sidmouth, and should it ever he T 2 made the type of a new genus, as proposed by Kiitzing, his spe- cific name, Grrjffithsianuin, may very deservedly be adopted. At present I prefer leaving it in Asperacoccus, from its very close affinity both with A. echmatus and A. Tkmeri. It appears to be of not unfrequent occurrence in the Mediter- ranean, several stations being recorded. I possess a fine specimen from Catania, given me by M.,Gussone; and I have gathered very large specimens at the Cape of Good Hope, much larger than any others that I have seen. It is very rare along the Atlantic coasts of France and Spain, as I am informed by M. Lenormand, who has kindly sent me a specimen gathered at Cherbourg ; and may probably occur in North Africa, but I have not received any specimens from that coast. In the British Seas it has as yet, only been found along the southern shores of Eng- land, and in the Channel Islands ; but it is not improbable that it may yet be discovered on the Irish coast, where so many southern forms reach their northern limit. Fig. 1. Asperococcus compressus : — the natural size. 2. A transverse section of the frond. 3. Portion of the same : more highly magnified 4. Portion of the membrane, viewed vertically. 5. Vertical section of a writs: — more or less highly magnified. n.,t. i xxw Scr. Rhodospi i |,,;l111 Oorallinea. Plate LXXIII. MELOBESIA AGARICIFORMIS, Haw. Gbn. Cb \... Frond, attached or free, either flattened, orbicular, simiated or irregularly lobed, or cylindrical and blanched, (never articulated), coated with a calcareous deposit. Fructification ; conical, sessile cap- lidia), scattered over the surface of the frond, and con- taining a tuft of transversely parted, oblong tebraspores. Melobesia (Lamour.), — from one of the Sea nymphs of Hcsiod. M ELOBESLA agariciformis • frond unattached, globular, hollow; foliations delicate, papyro-erustaceous, dense, erect, much lobed and sinuate, fastigiate; margin thin, entire. Millepora agariciformis, Pall. Elench. p. 263. Lam. An. s. vert. vol. ii. p. 204. 2nd. Edit.]). -2. 312. Millepora coriacea, Linn. Sj/st. p. 1285. Esp. Mill. t. 12. Millepora decussata? Ellis et Soland. Zooph. p. 131. t. 23. f. 9. Millepora tortuosa, Esper. t. 22. Nullipora agariciformis, Blainv. Actin. p. 605. Johns/. Br. Span, and Lilh. p. 241. woodcut, no. 23. Pollicipora agariciformis, Ehr. Beitr. p. 129. Lithophyllum expansum, Phil, in Jf'ieg. Arch. 1837. p. 38'.). e.vcl. syn. Melobesia expansa, Endl. Zrd Snppl. p. 49. Lithophyllum decussatum ? Phil. 1. c. t. 9. f. 4. Melobesia decussata? Endl. I. c. Mosco petroso, Impend. Hist. Nat. 600. cum. icone. Favagine (li Aristotele, specie prima, Giihioni. Op. t. 44. Hab. Lying on the sandy bottom of quiet bays, in 2-3 fathoms water. Rare. Roundstone Bay, Cunne, tiara, in one or two places only, abundant but very local, Mr. Md ('alia. Geogr. Distu. Atlantic and Mediterranean shores of Europe. Descr. Frond, unattached, forming globular or ovoid masses from four to eight inches in diameter, hollow within, seemingly from the decay of the central portion; very light, of a papery thinness and crustaceous substance ; com- 1 of innumerable simiated and lobed Laminae, issuing from a point towards the centre of the frond, and directed in a radiating manner to the circumference. In the centre of the frond the lamina? are much united ler, with vacant spaces and passages forming an irregular set of cham- bers; toward the circumference, the lobes are distinct from each other, standing erect, variously grouped; either simiated, or bent into semicircular forms, imbricating on each other, or curled round into little cups, or trumpet mouthed siphons. The apices of all are nearly fastigiate, and the margin i> iliin and quite entire. The colour when recent, is more or less ringed witl rosy-pink ; when dry it fades to a yellowish ; and when exposed to the sun becomes perfectly white, and rapidly cmmbles to powder. Under the microscope, a longitudinal section (when the calcareous matter has been removed by acid) shows a series of concentrical zones, formed of oblong cells separated by narrow spaces, filled with granular cellules, or possibly the appearance of bands may arise from the remains of calcareous matter. Fig. 3. represents a section of this description. I follow Decaisne in referring the Nidlvpora of Lamarck to the Melobesice of Lamonroivx, the latter name having been gene- rally adopted by such botanists as have described these pro- ductions, and the former by such zoologists as lay claim to them. Both names originated in 1816, and whichever have priority, it must be a narrow question of mouths, which I am unable to decide. The species here figured would belong to Spongites of Kiitzing, and to Lithophyllmn of Phiiippi ; but does not appear in the list of Melobesice given by Decaisne, nor yet, except under the more modern trivial name, deeussata, in that of Endlichcr. Nevertheless it is one of the earliest known species, as its nume- rous synonyines testify. The question of the vegetable nature of Corallines, among which the Melobesice take rank, may now be considered as finally set at rest, by the researches of Kiitzing, Phiiippi, and Decaisne, whose various memoirs, particularly that of the last named, have thrown much light on this obscure department of natural history, and fully confirmed the early views taken by Peyssonel, the elder Jussieu, Pallas, &c., in opposition to those of Ellis and most succeeding authors, who have associated them with the zoophytes. Outwardly, indeed, there is a striking resemblance, not less in form than in substance, between the Corallines and Corals ; but it is merely an outward resemblance. Whoever macerates a portion of one of these stony vegetables in weak acid, till the lime it contains be dissolved, will find that he has a structure of a totally different nature from that of any zoophyte, while it is perfectly analogous to that of many Algae. There is a near affinity, indeed, between the Corallince and the BhodomelecB ; or perhaps still more, the Condriece. Fig. 1. Melobesia A.GARICIFORMIS : — the natural size. 2. Portion of a lamina, with some of its epidermis removed, showing the banded arrange- ment of the cellules : — sliijlilh/ mtiijiiijied. 3. Longitudinal section of the same : — highly magnified. S». ELhodosjeb* u. Fam - OoralUnas. Plate LXXIV. MELOBESIA FASCICULATA, Zfcm (Jen. Chae. /VrW attached or free, either flattened, orbicular, smuated or irregularly lobed, or cylindrical and branched (never articulated), coated with a calcareous deposit. Fructification ; conical, sessile cap- sules {ceramidia) scattered over the surface of the frond, and containing a tuft of transversely parted, oblong tetraspores. Melobesia (lamour.) — from one of the Sea nymphs of Hesiod. Melobesia fasciculata ; frond unattached, roundish or lobed, stoney, much branched, fastigiate ; branches solid, thick, crowded together, cylin- drical or compressed ; apices truncate, broad, somewhat concave. Millepora fasciculata, Lam. An. s. vert. vol. ii. p. 203. 2nd. Edit. p. 211. Nullipoua fasciculata, Blainv. Actin. p. 605. Johmt. Br. Spon. and Lit//. p. 240. t. 24. f. 6. Lithothamnium crassum, Phil, in Wieg. Arch. 1837. p. 388? Hab. Lying on the sandy bottom of the sea, in 4-5 fathom water. Bound- stone Bay, Mr. Mc' " Calla. Geogr. Distr. Atlantic and Mediterranean shores of Europe. Descr. Fronds from one to three inches in diameter, roundish or irregularly lohed, composed of a solid central stony mass of no determinate form or size from which issue in all directions numerous short, thick, cylindrical or laterally compressed, crowded branches divided in an irregularly dichotomous manner, all nearly fastigiate, and remarkably truncated at the tips, which are moreover depressed in the centre. These broad, flattened or subconcave tip S are the least variable character of the species. In other respects it is subject to much variety. Sometimes the branches are reduced to mere rudiments, or very much flattened; and sometimes the frond presents little else than an aa^'reo-ate of thickened tabular pieces. The colour when recent, is a livid purple ; when dried, it fades to a dirty white. Under the micro- scope, after the calcareous matter has been removed by acid, a longitudinal section shows a fibrous surface, marked here and there by obscure zones ; and a transTerse cutting exhibits a radiate arrangement of the cells. Under a Lens of high power, the fibres resolve themselves into delicate, jointed, slightly mouibform filaments, easily separating one from another, toward the surface, but massed together into an irregularly cellular substance, at a greater depth within the frond. This species would fall under the genus Litliothamnium of Philippi, if it be not the same that he has described by the name L. crassum. I think it must be by a slip of the pen that Decaisnc unites these plants to Amphiroa, from which genus they differ in many ways, while they nearly, or altogether coincide with his own group Spongites in Mehbesia. Under the preceeding plant I have mentioned that the vege- table nature of the Corallines is now distinctly proved. The question still remains, whether the productions here called Meh- besia {Nullipora, Lam.) are independent vegetables ; or whether they be, as has been held by several naturalists, merely amor- phous states of the common Corallina officinalis. This is the view of the subject advocated by Dr. Johnstone, whose opinion, founded on observation, and as the opinion of an accomplished naturalist who has paid much attention to the lower tribes of animals, and is familiar with variations in form among sponges, nearly as wild as this would be, must not be too hastily con- demned. In the present state of my acquaintance with these plants I do not feel myself warranted in giving a direct negative to Dr. Johnstone, although, so far as my opportunities enable me to judge, I am not disposed to agree with his view of the subject. Granting that the base of Corallina officinalis is a calcareous ex- pansion resembling the frond of a Melobesia, I cannot therefore suppose that objects, like that figured in our last plate, together with the minute Melobesia pustulata, found on the leaves of the Zostera, are merely such bases which have omitted to develope true fronds. It should be borne in mind that the Melobesice have then - proper organs of fructification, and that these are similar in nature to, though slightly different in form from, those of Corallina ; and this I consider affords the strongest evidence of their independent nature, and the strongest probability of their being fully developed organisms. Still I will not say that it is conclusive evidence ; for we must remember that in plants of greatly more perfect organization, the Orchideee, more than one instance has occurred of floral organs so different in structure as to be referable to different genera, having been produced at dif- ferent times by the same root, and at last occurring together on the same stem ! If such things happen among flowering plants, what may we not expect on the confines of the Vegetable Kingdom? Fig. 1, 2. Melobesia fasciculata, different varieties: — tie natural sine. 3. A longitudinal section. 4. A transverse section of a branchlet -.—slightly magnified. 5. Cellular threads of which the frond is composed -.—highly magnified. S( r. Melanosperme*. flam. Dictyotece. Plate LXXV. CUTLERIA MULTIFIDA, Grev. Gen. Char. Boot clothed with woolly fibres. Frond fiat or compressed, eartilagineo-menibranaceous, ribless, somewhat fan-shaped, irregularly deft or dichotomous. Fructification, dot-like tufts of pedicellate utricles, scattered over both surfaces of the frond; each utricle con- taining several spores. Jxtkeridia on distinct plants, linear, trans- versely dotted, sessile on the sides of minute tufted filaments, occu- pying the position of true son. Cdtlebia [Grev.), — in honour of Miss Cutler, of Sidmouth, a distinguished British Algologist, Cvtleria tnulti/ida ; frond thickish, polymorphous, flabelliform, irregularly cleft into numerous narrow laciniae ; axils very acute ; apices atten- uated, pencilled. Cltlekia nvultifida, Grev. Alg. Brit. p. 60. t.10. Hook. Br. Ft. vol. ii. p. 281. Ifi/att . Alg. Dam. n. 61. Hare, in Mack. Ft. Hib. pt. 3. p. 177. Han. Man. p. 89. J. Ag. Alg. Medit. p. 40. Menegh. Alg. Itat. et Bairn, p. 201. Endl. 3rd Suppl. p. 25.' Kilt:. Fhjc. Gen. p. 339. Dickie, Ann. Xat. Hist. v. 14. p. 168. Zoxaria multifida, Ag. Sj>. vol. i. p. 135. Sgst. p. 267. Dictyota penieillata, Lamour. in Desv. Journ. Bo/, vol. ii. p. 41. Laniour. Fss. p. 58. Ag. Sj). Alg. vol. i. p. 139. Dictyota multifida, Bory, Morle, p. 75. no. 1756 Si'OROCHNUS inultifidus, Sprang. Syst. J'eg. vol. iv. p. 329. VlA a multifida, fin*. Fug. Bot. 1. 1913. Hab. On rocks and shells in the sea, in 4-15 fathoms water. Annual. Summer and autumn. Bare. Yarmouth, Mr. Turner and Mr. Wigg. Seaton and Torquay, Mrs. Griffiths. Sidmouth, Miss Cutler. Brighton, Mr. Borrer. Plymouth, Bev. W. 8. Wore. Bantry Bay, Miss Hutc&ins. Ballvcotton, Miss Boll. Kilkee and \Vieklow, II. H. II. Botind- stone Bay, Mr. Md Colla. Not found in Scotland? Geogr. DlSTB, Coasts of England and Ireland. Atlantic shores of France and Spain. Mediterranean Sea. Descr. Boot an expansion, densely eoateil with woolly, jointed, branching fibres. Frond from two to twenty inches in length, having a broadly wedge-shaped or fan-shaped general outline, but very variable in its minor divisions. The base is always broadly wedge-shaped, tapering into a short stem from a quarter to half an inch in length. The frond expands upwards, and is then often cleft into numerous wedge-shaped lobes, each of which is repeatedly and very irregularly incised from the apex downwards, the ultimate lacinia? being gradually narrower, and the apices acute. In some specimens the whole frond is cleft nearly to its base into narrow, irregularly dichotomous ribbons, from half a line to a line in breadth ; in others the laciniae are from half an inch to an inch broad, and do not extend below the middle of the frond. In some the apices are regularly fastigiate, and the outline nearly circular ; in other- they are of ven various Length. When in a perfect state the apices terminate in pencils of delicate jointed filaments (tig. 4), and a net-work of similar, but branching, filaments extends over tin whole surface of the frond, closely investing it ; and to this net -work the fructification is attached. Fructification, of two kinds, on distinct individuals; 1, pedi- cellate, oblong utricles, each containing about eight spores, clustered in minute tufts, which are plentifully dispersed over both surfaces of the frond, appearing like dots to the naked' eye. 2, sausage-shaped or linear, obtuse antheridia (?) attached to tufted filaments and scattered, like the utricles, over the whole frond. They are densely zoned with dotted lines. Substance cartilaginous, at first crisp, but becoming flaccid ; and then, on pressure, closely adhering to paper in drying. Colour a foxy olive. Structure very lax, the cells of the interior being few, of great size, and colourless. Cutleria mitltifida was discovered at Yarmouth by Mr. Dawson Turner, in August, 1804, and first described in English botany by Sir J. E. Smith. Although found on many parts of our coasts it is still considered a rare species, partly, perhaps, from its place of growth being beyond the limit of ordinary tides. Occa- sionally, after stormy weather, it is washed up in some plenty. The most abundant habitat yet discovered, is at Roundstone Bay, where, last summer, Mr. Mc' Calla dredged a large quantity in a remarkably fine state. This beautiful plant was selected by Dr. Greville to comme- morate the services rendered to British Botany by Miss Cutler, of Sidmouth, whose explorations of her neighbourhood have amply earned " the highest compliment that one botanist can bestow on another." No genus can be more distinct, and few, among the Didyotea, have a more delicate or curious structure. The fruit is very remarkable. The antheridia, described by Dr. Dickie in the ' Annals of Natural History ', I have only ob- served on a specimen sent me by Miss Cutler many years since, but similar bodies appear to be commonly borne by the exotic C. adspersa, on my specimens of which species I can find no other fruit. They bear a striking resemblance to the silicular fruit of Edocaqnis, and perhaps are organs of a similar nature. Eour species of Cutleria are described, with three of which oidy am I acquainted. Our C. vtudtifida is found on all the coasts of southern Europe; C. laciniata (which I only know by name), on the French coasts; and C. adspersa and partialis in the Mediterranean. The two latter arc very like each other, if they be really more than varieties of one species, but both are abundantly distinct from C. nmUifida, though evidently belonging to the same natural genus. Fie. 1. Cutleria multifida : — natural size. 8. A sorm of utricles attached °' to a fragment of the frond. 3. Utricles, separated. I. Apex of a lacima. 5. Antheridia. 6. Transverse section of the frond. 7. Longitudinal section : —all more or lea highly magnified. IlaleLXXil. Ser. Chwhospbbmm. Fan. Oaeillatoriea. Plate LXXYI. CALOTHRIX PANNOSA, A g . Gen. Char. Filaments destitute of a mucous layer, erect, tufted or aggre- gated, fixed at the base, somewhat rigid, not oscillating. Tube con- tinuous ; endochrome green, densely -annulated, at length dissolving into lenticular sporidia. Calothrix [Ag.),— from xoXAr, beautiful, and 8p\£, hair. Calothrix pannosa ; filaments elongate, rigid, very much curled and twisted, obtuse, densely interwoven together into lamellated tufts or honey-combed strata; endochrome blackish green, densely annulated. Calothrix pamiosa, Aij. in Bot. Zeit. vol. x. p. 635. no. 42. End!. 3rd Stippl. p. 13. Calothrix lamellata, Han-, in Herb. 1842. Has. Near high-water mark, growing either on rocks, on Fucus eanaUcu- latus, or on Corallina officinalis, &c. Perennial. Kilkee, W.H.H. Roundstone Bay, Mr. Mc' Calla. Sidmouth, Rev. R. Cresswell. Geogr. Distr. Adriatic Sea, at Trieste, C.Agardh. Descr. Filaments rigid, from a quarter to half an inch in length, very much curled, equal in diameter throughout, obtuse, very densely and intricately woven together, forming thi nlaniinae, which are either packed together in an irregular stratum with a bristling surface, or arranged with some regularity in a manner resembling honey-comb, small roundish or angular spaces being left between the lamina?, which unite at the edges in a sort of net-work. According to the object on which it grows, the plant varies ; that on the rock being more regularly honey-combed, and also more luxuriant than that which grows on Alga;. Endochrome dark green, closely annulated with strongly marked striae. I first observed this species at Kilkee, in the spring of 1S42, growing on Corallina officinalis, in rock pools near high water mark, a situation occasionally selected by the Coralline, but where it seldom reaches perfection. Believing at the time that my specimens belonged to an undescribed species, I communicated them to several friends under the manuscript name, C. lamellata. More recently I was pleased at receiving the same plant from the Itev. Mr. Cresswell, of Sidmouth ; and last summer, when at Roundstone, Mr. Mc' Calla pointed out to me a locality in winch it <*rows in great abundance and perfection, spreading over every v 2 JK Scr. EnoDOSPERMEiE. tfam. Ceramiea. Plate LXXVII. CALLITHAMNION TMPINNATUM, Ag. Gen. Char. Frond rosy or brownish red, filamentous ; stem either opake and cellular, or translucent and jointed ; branches jointed, one tubed, mostly pinnate (rarely dichotomous or irregular) ; dissepiments hya- line. Fruit of two kinds, on distinct plants ; 1, external tetraspores, scattered along the ultimate branchlets or borne on little pedicels ; 2, roundish or lobed, berry-like receptacles (favella) seated on the main branches and containing numerous angular spores. Callithamnion {Lynbg.), — from koXKk, beautiful, and 6apviov, a little shrub. Callithamnion trlphinatum; frond distichously branched, capillary, decomposito-pinnate ; plumules elongate, obovate, tripinnate above ; upper pinnae elongate, and pinnulate, lower short or abortive, each pinna having at its axil a minute pinnule ; pinnules long, setaceous ; joints of the stem 3-4 times, of the pinnse about twice as long as broad ; tetraspores oval, lateral on the axillary, and occasionally on the other pinnules. Callithamnion tripinnatum, Ag. Sp. Jig. vol. ii. p. 168. /. Ag! Alg. Medit. p. 72. Endl. 3rd Suppl. p. 34. no. 23 (but not of Harv. in Hook. Br. II. vol. \i.p. 346. nor of Wyatt, Alg. Damn. p. 186.). Mertensia tripinnata, Gratel. MS. sec. Ag. Hab. On marine rocks, at extreme low water mark. Annual. April, May. Very rare. Koundstone Bay, Mr. Me Calla. Geogr. Distr. Coast of Prance, Grateloitp. Mediterranean Sea, /. Agardhf West of Ireland, very rare. Descr. Fronds tufted, from one to two inches high, capillary, membranaceous, not gelatinous, perfectly distichous, having a circumscribed, somewhat fan- shaped outline, about triply pinnate; the primary pinnse, or plumules (one of which is represented at figure 2) having a narrow obovate outline, then- lower pinnae being very short, and simple, those approaching the middle of the rachis, gradually longer, those just beyond the middle longest, and those from thence to the apex gradually shorter. The upper and middle pinnae have their upper half furnished with slender, setaceous, elongate, patent, alternate pinnules ; their lower half naked, except the basal joint, which bears, almost invariably, at its upper side, or in the axil of the pinna, a solitary, and very frequently fertile, pinnule. Except for this basal pin- nule, the lower pinna; are quite naked, and generally very short or abortive. All the divisions are alternate. The joints of the stem and branches are pellucid, from three to four times longer than broad, cylindrical or some- what swollen at the nodes ; those of the pinnules are about twice as long as broad. Tetraspores oval, with wide borders, secund along the upper edge of the ultimate pinnules, very commonly on the axillary one. Favella unknown. Colour a full dark red. Substance delicate, and closely adhering to paper in drying. Having, in the ' British Flora ', committed the error of des- cribing a variety of C. thuyoideum under the name C. tripinnatum, an error unfortunately continued in Wyatt's admirable * Alga3 Danmonienses ", I have peculiar satisfaction in affording to the British botanist a figure of the true plant, of which I am the more certain, having compared our Irish specimens with one communicated to me from the Mediterranean, by my friend Professor J. Agardh. Notwithstanding some slight differences, I cannot but regard the Irish plant as belonging to the same species as that from Cette. The latter is more luxuriant, rather more robust, and has the ultimate ramuli rather longer, and perhaps it is more irregularly branched than ours. But the main character,— that by which the species is chiefly distin- guished, — of having a minute ramulus on the first joint of the pinnae, is common to both. Though the habit of C. tripinnatum is very like that of C. gra- cillimmn, it will be perceived that its microscopic characters have a greater resemblance to those of C. Borreri, from which the axillary ramulus, and the distichous growth chiefly separate it. Mr. Mc' Calla has, as yet, found very few specimens, and these accompanied C. thnjoideum, growing on the perpendicular sides of steep rocks at the extreme limit of low water. No other British station has yet been observed, but it can hardly be doubted that it will yet be added to the Flora of Devonshire or Cornwall. Grateloup's specimens were probably collected on the opposite shores of the channel. Fio- 1. Callithamnion tbipinnatum : — the natural she. 2. A plumule or ° pinnated-branch. 3. One of the smaller pinnse. 4. A pinnule, with tetraspores : — all more or less highly magnified. Ber. Melanosperme.e. Fam. Fucea. Plate LXXVIII. HDIANTHALIA LOREA, Lyngb. Gen. Char. Frond top-shaped. Receptacles very long, strap-shaped, re- peatedly forked, springing from the centre of the frond, filled with mucus traversed by jointed fibres, and pierced by numerous pores, winch communicate with immersed spherical conceptacles, containing either parietal spores, or (in distinct individuals) antheridia. Himan- thalia (Zyngb.) — from i/u*r> a strap, and Bakos, a branch (or S\s, the sea.) Himaxthalia hrea ; frond top-shaped, at length cup-shaped, stalked ; re- ceptacles repeatedly dichotomous, tapering more or less at the apex. Himaxthalia lorea, Lyngb. Hyd. Ban. p. 36. t. 8. Grec. 17. Edin. p. 285. Gaill. in Bid. 8c. Xat. vol. 53. p. 357. Grev. Alg. Brit. p. 20. t. 3. Hook. Br. Ft. vol. ii. p. 269. TJ'yatt, Jig. Banm. no. 3. Hare, in Mack. El. Hib. part 3. p. ]70. Hare. Man. p. 22. Kiitz. Phyc. Gen. p. 351. Endl. 3rd Suppl. p. 29. Feces loreus, Linn. Syst. Xat. vol. ii. p. 716. Gm. vol. ii. p. 1382. Huds. El. Ang. p. 583. Lightf. El. Scot. p. 920. Ft. Ban. t. 710. With. Ar. vol. iv. p. 96. Stack. Xer. Brit. p. 37. t. 10. E.Bot.X.569. Turn. Syn. Fuc. vol. ii. p. 246. Hist. t. 196. Lamour. Ess. p. 19. Ag. Sp. Alg. vol. i. p. 98. Ag. Syst. p. 280. Spreng. Syst. Feg. vol. iv. p. 316. Feces elongatus, Linn. Sp. PL vol. ii. p. 1627 (Arc/, syn. Moris). Syst. vol. ii. p. "7 16. Gm. vol. ii. p. 1381. Gm. Hid. Fue. p. 103. (excl. syn Ht'ds.). Poena longo ansrusto crassoque folio, Eaii. Syn. p. 43. n. 11. Feces fungis atfinis, Eaii. 1. c. p. 43. u. 15. Hab. On rocky sea shores, near low water mark. Annual? Winter and spring. Common. Geogr.Distr. Atlantic shores of Europe from Iceland {Mohr.) to Portugal {Brotero). Eastern coast of North America. Descr. Boot scutate Fronds tufted, when young narrow obconical, gradually becoming wider above, and finally being top-shaped, depressed in the centre, with an expanded circular rim, thus becoming slightly cup-shaped, or pezizaeform. Beceptacles springing from the centre (i.e. the* apex) of the cup-like frond, vaiying in length from two to ten, or according to some authors, to twenty feet; from a quarter to half an inch in width, compressed, linear, repeatedly dichotomous, tapering at the apices into more or less acute points. Internally these receptacles are filled with a watery gelatine traversed by confervoid filaments. Their outer coat is firmly cellular, and pierced by numerous pores beneath each of which is formed a small sphe- rical chamber or conceptacle. The fructification is dioecious. In some individuals the conceptacles contain tufts of antheridia, attached to branching filaments, similar to those of Fucus. In others they contain, immersed among confervoid filaments, three or four large, roundish, olive-coloured spores, which divide internally at maturity into four sporules. Colour, a dark olive, occasionally pale yellowish. Substance coriaceous. This well-known plant, which, with some schooling, we have contrived to bring within the narrow compass of our plate, is very common on most of the rocky Atlantic coasts of Europe and North America, but is not found in the Mediterranean. Authors are at variance as to its duration ; Turner and Car- michael asserting that it is a perennial ; Greville and Mrs. Grif- fiths that it is annual. Certain it is that the plant appears to reach to its full growth within the year, and that vast multitudes of fronds then decay ; whde their receptacles are detached, and drift ashore in tangled strata. Possibly some survive to a second season, and throw out new receptacles ; for I am unwilling to set aside the evidence of so close an observer as the late Captain Carmichael, who declares that he has seen old fronds which had shed their first receptacles, throw out others, which latter fre- quently spring, according to the same authority, from some ex- centric point of the disc. I have, I must add, repeatedly and in vain sought for instances of this second growth, and am therefore disposed to regard the species as being, under common circum- stance, an annual, — granting that it may occasionally be biennial, from the influence of local causes. The common name is Sea Thongs, of which the lengthy Greek by which it is known to botanists is nearly a literal translation. It is used in the manufacture of Kelp, in which salt it is said to be rich, though inferior in this respect to some of the true Fuel. Fiff. 1. Himanthalia lohea, a small specimen: — the natural she. 2. Cross section of the receptacle. 3. Enlarged view of a conceptacle : — in situ. 4. A spore, containing four sporules, and surrounded by hyaline filaments. Ber. MBLANOSPBBMas. Pam. bmmariea. Plate LXXIX. ALARIA ESCULENTA, Grev. Gen. Char. Root fibrous. Frond stipitate, membranaceous, furnished with a percurrent, cartilaginous midrib ; the stipes pinnated with ribless leaflets. Fructification, an oblong sorus, formed of pyriform, vertical tetraspores, and situate in the accessory leaflets. Alaria (Grev.), — from ala, a icing ; in allusion to the winged frond. AiABiA esculenta; frond elongated, lanceolate, entire; rib narrow, cylin- drical; leaflets linear-oblong or cuneate. Alaria esculenta, Grev. Ala. Brit. p. 25. t. 4. Hook. Brit. Ft. vol. ii. p. 271. Hart, in Mack. Ft. Hih. part 3. p. 171. Wyatt, Alg. Damn. no. 203. Han. Man. p. 23. Fust, and Bupp. p. 1 1. t. 17. Endl. 3rd Suppl. p. 28. Kite. Phyc. Gen. p. 347. t. 32. f. 1. Laminaria esculenta, Lyngb. Hyd. Ban. p. 23. Ag. Sp. Alg. vol. i. p. 110. Syst. p. 269. Hook. Ft. Scot, part 2. p. 98. Grev. Fl. Edin. p. 282. La Py/aie, Ann. Sc. Nat. vol. iv. p. 178. t. 9. f. D-F. Spreng. Syst. Feg. vol. iv. p. 326. Agarum esculentum, Bory. Diet. Class. Nat. Hist. vol. ix. p. 194. Fccus esculentus, Finn. Mtad. p. 135. Fl. Dan. p. 364. Syst. Nat. vol. ii. p. 718. Gmel. Syst. Nat. vol. ii. p. 1389. Fl. Dan. t. 417. Light/. Fl. Scot. vol. ii. p. 938. t. 28. Huds. Fl. Aug. p. 578. With. vol. iv. p. 93. Turn. S V n. Fue. vol. i. p. 104. Turn. Hist. t. 117. Eng. Bot. t. 1759. Esper. Lc. Fue. vol. ii. p. 30. t. 126. Fccus fimbriates, Gm. Hist. Fue. p. 200. t. 29. f. 1. Fucus tetragonus, Good, and Woodic. in Linn. Trans, vol. iii. p. 140. Fccus teres, Good, and Woodic. in Linn. Trans, vol. iii. p. 140. Fuel's phuiatus, Fl. Nort. vol. i. p. 96. Fucus scoticus latissinius edulis dulcis, Rail. Syn. p. 46. n. 30. IIab. Fringing precipitous rocks, at low-water mark. Perennial. \\ inter and spring. Abundant on the shores of Scotland, and of the north and west of Ireland. Cumberland, Hudson. Anglesea and Isle of Man, Rev. H. Bootes. Durham and Northumberland, Winch. Corn- wall, Turner. North coast of Devonshire, Mrs. Griffith. Weymouth, Stackhome. Orkney, Bee. Mr. (Houston. Geogr.Distr. Abundant in the Arctic Ocean aud Northern Atlantic. Iceland, Lyngbye. Northern Pacific. Sitka. Kanitsehatka. Atlantic shores of France, Lenormand. Descr. Root consisting of several radiating, cylindrical, branching and grasping fibres. Stem as thick as a small goose-cpiill, naked in its lower part for the length of 2-4 inches ; then pinnated with leaflets for 1-3 inches more, and finally terminating in the midrib of the frond. Leaflets numerous, 2-4 inches in length, and from a quarter to half an inch in breadth, rib-less, filiform at the base, gradually widening upwards, geuerally obtuse Frond, when fully grown, from 3-20 feet in length, and from 2-8 inches in breadth, mem- branaceous, entire, splitting obliquely towards the midrib, linear or lanceo- late, tapering to each extremity, the surface perforated with minute pores, producing tufts of fibres. Fructification forming an oblong, reddish brown, X tluckened sorus, on both surfaces of the leaflets, consisting of a vast number of narrow-pyriform, stipitate, vertical spores, closely packed together, and each separating at maturity into four sporules, in a cruciate manner. Colour a transparent yellowish olive. This beautiful plant, which is scarcely known on the southern coasts of England, abounds on all the Atlantic shores of the British Islands, and extends throughout the whole of the north- ern Atlantic and Pacific Oceans. The roughest water seems to be most favourable to its existence, and I observe that it reaches its greatest size and most luxuriant growth on some of the most exposed parts of our western coasts. Yet the delicate membrane of its leaf is easily torn, and in large specimens is very rarely found free from laceration. It appears to be perennial ; the new growth being produced at the base of the leafy-frond, as observed by Mrs. Griffiths in all the Laminariece. This portion is always of a much paler colour than the old, and soon after the commencement of the growing season, the line of demarcation becomes distinctly visible : and when it has progressed for some time, a contraction takes place at the base of the old leaf, which gradually increases till the latter falls, and a new frond is formed. The renewal of the leaflets appears to be conducted in a similar manner. The fructification commonly to be met with on full grown specimens, consists of innumerable slender spores, closely packed together, which according to Dr. Joseph Hooker, are compounded of four sporules, divided by two lines, crossing at right angles. The same close observer has discovered similar tctraspores in many others of the Laminariece, in which, previously, the spores were supposed to be simple. Maria esculenta is eaten in some parts of Scotland, and Ireland, as well as in Iceland, and the Fceroe Islands. For this purpose the midrib, stripped of its membrane, only is used. It has a sweetish taste, but is rather insipid. In Scotland it is called Badderlocks or Hen- Ware ; and in Ireland, according to Dr. Drummond, Murlins. Four other species, all nearly allied to this, are known to botanists. They are natives of the northern shores of North America, and of Asia. Fig. 1. Alaria esculenta; a srnall specimen: — of the natural size, 2. A leaflet with a sorus: — slightly magnified. 3. Section of the sorus. 4. Some of the spores removed : — highly magnified . Ser. Rhodospekme^e. Fain. Ceramics. Plate LXXX. PTILOTA PLUMOSA, Ag. (Jen. Char. Frond inarticulate, linear, compressed or flat, distichous, pec- tmato-pinnate ; the pinnules sometimes articulate. Fructification, of two kinds, on distinct individuals; 1, tefraspores attached to, or immersed in the ultimate pinnules ; 2, roundish, clustered, receptacles (favella) surrounded by an involucre of short ramuli. Ptilota {Ag.) — from TrnXwTos, pinnated. Ptilota plumosa ; frond cartilaginous, decompound ; secondary branches bi-tripinnate, elongate; pinnae and pinnules exactly opposite, the latter subulate, cellular, traversed by a narrow, immersed, jointed filament ; tetraspores on short pedicels, fi-inging the margin of the pinnules; flavellse pedunculate, with an involucre of 6-8 subulate ramuli. Ptilota plumosa, Ag. Sp. Alg. vol. i. p. 385. {excl. var. /3.) Ag. Syst. p. 195. Lyngb. Hyd. Ban. p. 38. t. 9. Grev. Ft. Mm. p. 297. Spreng. Syst. Veg. vol. iv. p. 34-1. Hook. Ft. Scot, part 2. p. 106. Grev. Alg. Brit. p. 155. 1. 16. Hook. Br. Ft. vol. ii. p. 84. Ilarv. in Mack. Ft. Rib. part 3. p. 204. Harv. Man. p. 84. Endl. 3rd Suppl. p. 36. Post, and Rupp. p. 16. Kilts. Phyc. Gen. p. 378. t. 46. f. 6. Ceramium plumosum, Roth. Cat. Bot. vol. iii. p. 133. Ag. List, p.' 17. Plocamium plumosum, Lamour. Ess. p. 50. Pucus plumosus, Linn. Mant. p. 134. Syst. Nat. vol. ii. p. 718. Huds. Ft. Angl. p. 587. Gm. Hist. Fuc. p. 152. Ft. Dan. t. 350. Light/. Fl. Scot. vol. ii. p. 955. With. vol. iv. p. 120. Esper. Lc. Fuc. vol. i. p. 92. t. 45. Fl. Norv. vol. ii. p. 91. Linn. Trans, vol. iii. p. 18S. Turn. Syn. Fuc. vol. ii. p. 296. Turn. Hist. Fuc. t. 60 {excl. var. £.). Eng. Bot. 1. 1308. Hab. Parasitical on the stems of Laminaria digitata. Perennial. Sum- mer and autumn. Frequent on the shores of Scotland, and of the north and west of Ireland. Holyhead, Mr. Ralfs. Scarborough, . Geogr. Distr. Distributed throughout the Arctic, the North Atlantic and North Pacific Oceans. Davis's Strait, Turner. Iceland, (Eder. White Sea, Greenland, Sitka, Unalaska, Posteh and Rupprecht. Arctic America, Richardson. Kanitschatka, Bongard. Norway and Sweden. Descr. Root scutate. Fronds tufted, 4-12 inches in length, compressed, linear, from the thickness of a hog's bristle to nearly a line in diameter, irregularly divided. Secondary branches distichous, 1-3 inches in length, patent, linear- oblong or obovate in circumscription, bi-tripinnate, the pinna; and pinnules very patent, scarcely a hue asunder, gradually increasing in length toward the middle of the branch, and diminishing to the apex. Ultimate pi/itiu/rs closely pectinate, awl-shaped, acute, cartilaginous, sub-opake, their outer coat formed of numerous angular cellules, through which is visible a jointed 2 x axis or string of lanre cells, which runs through the pinnule as well as (wnh some modification) through every part of the frond. Fructification: 1. roundish, tripartite, external tetraspores seated on minute pedicels, which fringe the margin of slightly abbreviated pinnules : 2, on distinct plants, clustered faxetta:, surrounded by an involucre of several subulate ranvuli, and borne on the apex of abbreviated pinnules. Colour a da*, fidl red, occasionally with a brownish tinge. SMa»ce cartilaginous, rather rigid, more or less perfectly adhering to paper in drying. Our figure and description apply solely to the var. a. of Turner, which, though abundant on the shores of Scotland and the north and west of Ireland, is rare in England, and quite unknown on our southern shores. As far as my experience goes it invariably grows on the stems of Laminaria digiiata, which it often clothes with a rich feathery fringe. The var. j3. of Turner, which is the common plant of the south of England, as invariably grows on rocks ; and preserves its characters so constantly that I cannot help regarding it, with Kiitzing, as a distinct species. In doing so I am reluctantly compelled to dissent from the opinion of Mr. Turner, who says, " that no Foots whatever exhibits more regular gradations between the most narrow and delicate, and the broadest and most cartilaginous individuals ; in consequence of which no attempt was ever previously made to separate it into different varieties." I cannot observe this gradation ; to me the two forms appear to be easily distinguishable by the naked eye in every case ; and present very distinct microscopic characters. Besides this, their geographical range and habitat are different ; for though on our northern shores both are found, yet further north the var. a. alone is met with ; and further south, as on the southern shores of England and the shores of France and Spain, the var. /3. is exclusively seen. Add to this, that the first is never found on rocks, and the last always is ; that the parasites which commonly infest them are different ; that one is a far stouter and more cartilaginous plant than the other ; that the microscopic appearance of their pinnules is very dissimilar ; and we shall, I thinlc, have sufficient specific characters to separate them. Fie 1 Ptilota ploiosa:— of the natural ste. 2. A pectinated pinnule. 3. One of the ultimate laciniae. 4. An involucre. 5. Favells, removed from the same. 6. A lacinia bearing tetraspores. 7. One of the tetraspores :— mart or lens highly magnified. fc Ser. Khodosperme/E. ram. Ceramiece. Plate LXXXI. CALLITHAMNION FLOCCOSUM, A g . Gen. Char. Frond rosy or brownish red, filamentous ; stem either opake and cellular, or translucent and jointed ; branches jointed, one-tubed, mostly pinnate (rarely dichotomous or irregular); dissepiments hya- line. Fruit of two kinds, on distinct plants; 1, external tetraspores, scattered along the ultimate branchlets or borne on little pedicels ; 2, roundish or lobed, berry-like receptacles (favellce) seated on the main branches, and containing numerous, angular spores. Callithamion (Lyugb.) — from koXKis, beautiful, and dapviov, a little shrub. Catjjthajtnion floccosum ; frond capillary, very flaccid, remotely much branched; branches alternate, erecto-patent, articulated; every joint producing a pair of opposite, simple, subulate, erecto-patent, minute ramuli ; tetraspores elliptical, pedicellate, produced on the ramuli, near their base. Callithamnion floccosum, Ag. Sp. Alg. vol. ii. p. 158. (excl. Syu. Dillw.) Endl. 3rd Suppl. p. 34. Callithamnion plumula, Lyngb. Hyd. Dan. p. 127. (excl. var. /3.) Callithamxion Pollexfenii, Harv. in Ann. Nat. Hist. vol. xiv. p. 186. t. 5. f. 5—7. Conferva floccosa, Ft. Ban. t. 828. Hab. On submarine rocks, near low-water mark. Annual. Spring. Very rare. Orkney Islands, Rev. J. H. Polle.rfen. Aberdeen.^. Dickie. Geogr. Distr. Coast of Norway. North of Scotland. Descr. Fronds densely tufted, from one to four inches in length, capillary, very flaccid, irregularly divided into several principal branches, in an alternate or subdichotonious manner, the furcations rather distant ; main branches either naked or furnished at intervals with short, closely branched or multifid lateral secondary branches, having an obovate outline ; all the divisions alternate, the axils acute, and the branches and their secondaries erecto- patent or erect. Filaments pellueidly articulate throughout, the articula- tions from two to four times as long as broad, each having a pair of oppo- site, subulate, simple, minute ramub, not half a hue in length, springing from a short distance above the middle of the articulation. Tetraspores elliptical, borne on short, accessory processes of the ramuh, issuing either on the inner or outer face. Fai-ella unknown in this country. In the year 1S40, I received, from the Rev. J. H. Pollexfen, a specimen of this plant, gathered by him, in the previous summer, in one of the bays of the Orkney Islands, and not find- ing it to agree with the specific character of any species published by Agardh, I published it as new, in the ' Annals of Nat. History for 1844, under the name of C. Pollexfenii, as a just tribute to its acute discoverer. At that time I had no suspicion that it could be the C.floccosum of Agardh, because the character he gives " ramellis oppositis ascendenti-patentibus sursum pecti- nato-pinnatis, pinnis simpliciusculis," by no means answers to the present individual, and agrees very well with a common variety of C. Plumula. Forming my judgment on the words " sursum pectinato-pinnalis ;" as well as on Agardh's reference to Dillwyn's Plate 50. f. A, and on the note appended to his description, " Hinc hsec icon semper nobis dubia fuit, usque dum Hookerus specimen Conferva Plumula, Dillw. misit, quod omnia explicavit, et nobis persuasit, dua individua diversse speciei picta esse ;" I could not believe otherwise than that his C.floccosum was founded on a bad specimen of C. Plumula, for I knew that Sir W. J. Hooker could never have sent Agardh a specimen of my C. Pol- lexfenii, which did not exist in his Herbarium, until Dr. Dickie communicated it in 1844 ; and still less could it have been the plant intended by Dillwyn's figure. Were there no other grounds, therefore, for upholding Agardh's C.floccosum, than the description he has given of it, that species must be erased, and its synonymes transferred to C Plumula. But the real founda- tion of C. floccosum rests, on the figure in ' Flora Danica,' and the description given by Lyngbye, in his excellent work, above quoted. My error consisted in having omitted to refer to that figure and description ; for though the figure is not very accurate, yet it certainly is more characteristic of our plant than of C. Plumula; while the description given by Lyngbye, and which was taken from an authentic specimen of the plant figured in ' Flora Danica,' answers in all respects to my C Pollexfenii. I am compelled, therefore, to restore the specific name, under which this species was first published. C.floccosum would appear to be peculiarly a northern plant, confined, so far as we know, to the coasts of Norway, and the north of Scotland, — in both which countries it is of extreme rarity. Fig. 1. Callithamnion floccosum; — of tin- natural si:t\' 2. A branch : — magnified. 3. Portion of the same. 4. Hamuli with tetraspores. 5. A tetraspore : — highly magnified. Ser. Melaxosperme.e. Fam. Chordariea. Plate LXXXII. MESOGLOIA VIRESCENS, Cam. Gen. Char. Frond filiform, muck branched, gelatinous. Axis composed of loosely packed, longitudinal, interlaced filaments, invested with gelatine; the periphery of radiating, dickotomous filaments wkose apices produce clusters of club-skaped, moniliform fibres. Fructijica- iion, obovate spores, seated among the apical fibres. Mesogloia (Ag.) from mej,esseria alata, /3. angustifoba, Lyngb. Hyd. Ban. p. 8. (?) Rhodomenia rostrata, J. Ag. MSS. Gigartina purpurascens, y. rostrata, Lyngb. Hyd. Ban. p. 46. t. 12. fide J. Ag. (but. the figure is not characteristic) . Gelidium? rostratum, Griff, in Han. Man. p. 82. Fucus alatus, y. angustissitnus, Tarn. Syn. Fuc. vol. i. p. 145. Turn. Hist. 1. 160. fig. k-l. Fucus alatus, junior, Gm. Hist. t. 25. f. 2. Hab. Parasitical on the stems of Laminaria digitata, often accompanying Del. alata. Perennial. Winter and Spring. Scarborough, Mr. l'llrhford. Lossiemouth, Morayshire, Mr. Brodie. Aberdeen, Dr. Dickie. Orkney, Rev. J. H. Poltexfen. Galway, Mr. Beilly. Corn- wall, Mr. Raffs. Kingstown, Mr.' And ran. Geogr. Distr. Arctic Sea, and Northern Atlantic Ocean. Greenland. Norway ? Descr. Root, a small disc. Fronds tufted, 4-8 inches long, nearly cylin- drical below, compressed and two-edged above, not half a line in diameter, becoming gradually more slender towards the tips, much and irregularly branched. Branches distichous, irregular, alternate or subdichotomous, frequently bare of ramuli in their lower part ; above more or less amply furnished with patent, once or twice forked, ramuli from a quarter to half an inch in length. Apices acute. Colour a very dark red. Substance car- tilaginous, rather flaccid. Fructification ; 1, tubercles mostly immersed in small accessory ramuli, springing from the axils of the upper branches, spherical, containing a moderately dense mass of spores, sometimes immersed in the apices of the frond. 2, 'tetraspores contained iu the inflated tips of the branches, or in small, simple or forked, spindle-formed, accessory ramuli, seated in the axils of the upper branches. * In this species the membrane is obsolete, the frond consisting altogether, or very nearly, of midrib. It is nearly forty years since Mr. Brodie first noticed the plant here figured, and sent specimens to Mr. Turner, by whom they were then considered to be a variety, which he called anyustissima, of Detesseria alata ; and in this judgment he was generally followed till the year 1840, when, in deference to the repeated protests of Mrs. Griffiths, I ventured, in the ' Manual,' to separate and describe Mr. Brodie's plant under the temporary name of Gelidium ? rostratum, recommending it to the notice of observers, and adding that "my own opinion on this puzzling matter was not very decided." Were all the specimens now before me equally characteristic as the one I have figured, I should have no hesitation in adding mine to the other opinions in favour of this plant ; but unfortu- nately I possess some, in which I can clearly trace the compressed edge of the frond passing into a very narrow membrane ; and others which seem to be exactly intermediate between very narrow alata, and true anyustissima. I am therefore now persuaded that Mr. Turner's judgment was strictly correct ; and Dr. Dickie, who has had the best opportunities., of studying it in its living state, writes, " Both plants grow together upon Lam. diyitata ; both are in fruit at the same time ; and in making up packets of duplicates I have often been puzzled whether to call my speci- mens G. rostratum or D. alata." Mrs. Griffiths, however, adheres to her already recorded opinion. " I have always ", she says, "acted on the maxim of my first instructor, Bishop Goodenough, who in one of his early letters wrote, « never let what I or any one else may say weigh against the evidence of your oton senses '; therefore, when I see the young, tender and perfect shoots of one plant furnished with a membrane, however bare the rest of the plant may be, and the equally young and tender shoots of another perfectly naked, though some of the branches are compressed, I must decide that they are not the same species, particularly as the difference has been constant for so many years." Whichever opinion be eventually adopted, it, must at least be acknowledged that I), anyustissima is a very remarkable form, and as such deserving of a place in this work. Fie 1. Delessekia ahgustissima .—of the natural size. 2. Portion of a branch with tetraspores. 3. An axillary ramulus, with the same. 4. Portion of a branch with tubercles. 5. An axillary ramulus containing a tubercle. 6. Portion of a branch with the commencement oi a winged margin -.—all magnified. 7. Fragment of the surface of the frond. 8, y. Transverse sections 'of different specimens -.—highly Magnified. Ser. Chlorosperme.s. Fam. Camfe/roea. Plate LXXXIV. CLADOPHORA MACALLANA, Haw. Gen. Char. Filaments green, jointed, attached, uniform, branched. Fruit, aggregated granules or zoospores, contained in the joints, having, at some period, a proper ciliary motion. Cladophora (Kiitz.) — from ka°P*°, to dear. Cladophora MaeaUanA; filaments setaceous, rigid, full green, very flexuous, loosely bundled together, excessively branched ; branches alternate or rarely opposite, zigzag, very patent ; raniuli short, recurved, simple, or pectinated, obtuse; articulations twice or thrice as long as broad; endochrome rather dense. Hab. On the saudy bottom of the sea, in 4-10 fathom water. Annual. Summer. Dredged in Roundstone Bay, abundantly, Mr. Mc'Calla. Geogr. Distr. West of Ireland. Descr. Root not exactly known. Filaments forming crisped subcylindrical bundles from six to twenty inches in length, rigid, bristling (not collapsing) when removed from the water, of a rich, shining, grass-green colour, much branched, and inextricably tangled together, rather brittle. Brandies very flexuous or bent in a zigzag manner, irregular in length and disposition, some- times opposite, more usually alternate or secund ; sometimes divided in a sub-dichotomous manner, very patent, with wide axils ; furnished with a second and third series of smaller branches, and these clothed at short in- tervals with short ramuli. Raniuli alternate or secund, very patent or re- flexed, short, cylindrical, obtuse, either simple or more usually pectinated on their upper side with short, one- or two-jointed processes. Apices all very blunt. Endochrome rather dense, recovering its form, in a degree, when moistened after having been dried. In drying it very imperfectly adheres to paper. This handsome Cladophora was, in 1840, communicated to me by Mr. Mc'Calla, as a new species, but it was not until last summer that I had an opportunity of seeing it in its place of growth, and examining it in a fresh state. At Roundstone, in August, I dredged it in considerable plenty, and convinced myself that it was quite distinct from any described British species ; and as I have reason to believe it to be new to botanists, it gives me great pleasure to give it the name of its discoverer, who has well earned such a tribute by the many additions he has made both to the Fauna and Flora of the west of Ireland ; and who is now engaged in the preparation of an excellent work containing dried specimens of Irish Algae, one volume of which has already appeared.* Professor Kutzing, who has studied this puzzling genus with much care, and to whom I sent a specimen, writes me that it is quite new to him, and that he considers it to be a good species, allied indeed to C. alyssoidea, Menegh., " but more rigid, less thick, with longer joints, and a different ramification." Mrs. Griffiths has also expressed a similar opinion. When growing, it has very much the appearance, at first sight, of C. rectangularis, so much so, indeed, that until the ramifica- tion be closely looked to, and the alternate or secund ramuli be observed, it might be mistaken for that species. It grows in the same locality, and occurs in similar loosely-bundled masses, and often accompanies C. rectangularis in the same dredge. It possesses the same rigid substance as that species, and the same glossy, bright green colour, except when it is, as most of my specimens are, infected with Cocconeis aggregata, which as Dr. Kutzing remarks, not only change its colour, but prevent its adhering to paper. * " Alga; Hibemicee," by William Mc'Calla, Associate of the Edinburgh Bo- tanical Society. S. B, Oldham, Dublin. 1845. Imp. 4to. Pig. 1. Cladophora Macallana : — of the natural she. 2. Part of a filament ; °— magnified. 3. Ramulus : — more highly magnified. Ser. Rhodosperme./k. Fam. lihodomeka. Plate LXXXV. RYTIPHLtEA PINASTROIDES, [A 3 .) Gen. QiKau.* Frond, filiform or compressed, pinnate, transversely striate, reticulated: the axis articulated, composed of a circle of large, tubular, elongated cells (siphons) surrounding a central cell ; the periphery of several rows of minute, irregular, coloured cellules. Fructification of two kinds, on distinct individuals ; 1, ovate capsules {ceramidia) con- taining a tuft of pear-shaped spores ; 2, tetraspores, contained in minute lanceolate receptacles (stichidia), in a double row. RytiphljEA (Ag.) — from pvrls, a wrinkle, and #Xoioj, the bark; because the surface is transversely wrinkled or striate. RmmLEA pinastroides ; frond terete, irregularly branched ; lesser branches pectinato-pinnate ; the pinnae secund, with their apices more or less hooked inwards. Rytiphl/EA pinastroides, Ag. Syn. p. 25. /. Ag. Alg. Medit. p. 145. Emit. 3rd Suppl. p. 48. Rhodomela pinastroides, Ag. Sp. Alg. 1. p. 381. Ag. Syst. p. 200. Sprenq Syst. Veg. 4. p. 343. Grev. Alg. Brit. p. 104. t. 13. Hook. Br. Ft. vol. ii. p. 294. Wyatt, Alg. Damn. no. 112. Harv. Man. p. 68. Halopithts pinastroides, Kiitz. Pliyc. Gen. p. 433. t. 52. f. 2. GrlGARTlNA pinastroides, Lyngb. Hyd. Dan. p. 45. Ceramium incurvum, Dec. Ft. Fran. vol. ii. p. 33. Fucus pinastroides, Gm. Hist. Fuc. p. 127. t. 11. f. 1. Good, and Woodic. in Linn. Trans, vol. iii. p. 222. Turn. Syn. vol. ii. p. 346. Turn. Hist. 1. 11. Stack. Ner. Brit. p. 74. t. 13. Eng. Bot. t. 1042. Fucus incurvus, Huds. M. Aug. p. 590. With. vol. iv. p. 115. Hab. On sub-marine rocks, near low-water mark. Perennial. Winter. On the shores of the south of England, in several places. Jersey, Miss White, and Miss Turner. Geogr. Distk. Atlantic shores of Prance and Spain. Mediterranean Sea. "Freroe Islands," Lyngbye (very doubtful). New Zealand, Sir J. Banks. Ceylon, Sir J. E. Smith. Descr. Root an expanded, disc. Fronds tufted, 4-10 inches in height, cylin- drical, about as thick as whip-cord below, much and irregularly branched and bushy, somewhat fastigiate : the main branches alternate or subdichotomous, densely clothed in their lower part with short, subulate, simple, erecto-patent ramuli, which occasionally give a shaggy character to the bases of old fronds; ; and in then upper, set with elongate, patent or recurved, pectinato-pinnate branches, whose apices are, especially in young fronds, very generally rolled inwards or hooked. These lesser branches are pectinate along their upper side with a double set of subulate ramuli, secundly disposed, generally in pairs, at short intervals, but occasionally somewhat irregularly inserted; all very erect, with straight or hooked apices, and somewhat narrowed at the base. Both branchlets and ramuli are marked with dark, transverse lines, or spurious articulations, at short intervals, an appearance caused by the arti- culated, polysiphonous axis of the frond being seen through the subtrans- parent cells of the periphery. Fructification ; 1, ceramidia ovate, on longish pedicels, borne along the inner faces of the secund ramuli. 2, Stiehidia, which occupy a similar position on distinct plants, and are shortly stalked, lanceo- late, and uncinate. Tetraspores triangularly parted. Substance cartilaginous and' tough ; very rigid when dry, and not adhering to paper. Colour a dark, dull red, becoming black in dying. This is one of those plants which, abundant along the shores of southern Europe, reaches its northern limit on the south coast of England ; for the report of its having been gathered in the Eceroe Islands, as well as the station " near Dublin," given by Dr. Scott, are, I fear, founded in error. It is assuredly a southern species in its affinities and distribution. We have the high authority of Turner, that it occurs in Ceylon and in New Zealand ; otherwise I should have suspected some mistake in these stations also. The genera Rytiphlaa, Bhodomela and Poli/siphonia have so many points of structure in common, and differ by characters of such secondary importance, that it is sometimes a question to which a plant should be referred. The articulated PolysiphonicB indeed, are readily enough distinguished from the species of the two former genera; but it is by an artificial character. For species otherwise closely related, as P. subuli/era and P.fruti- culosa, would, were the genus divided on this character, be placed in opposite groups. This would hardly be considered natural. But then it becomes a question how the inarticulate Polysiphoneas are to be separated from the Bhodomela; and Bytiphlaa. Natural habit generally decides it, for there is little structural difference. In the true Bhodomela, indeed, as B. subfusca, and B. lycopodioides, the absence of a jointed axis, composed of a circle of elongated cells, affords a ready character. But some of the exotic species have more or less evident traces of such a structure. In Bytiphlaa, as here defined, this struc- ture exists ; and there is nothing to distinguish the group from the inarticulate Polysiphonia, except the position of the tetra- spores, and some difference of habit. Fi". 1. Eytiphl.ea Pinastroides : — of the natural she. 2. A branch with ° stiehidia. 3. A stichidium. 4. A tvtraspore. 5. A branch with a 6. A ceramidium. 1. Spores, from the same 8. A Longitudinal section of the frond. 9. A transverse semi-section of the same : — all more or less magnified. \ ^ \ \ \ \ w \ w \\ \ 4. ■ \v \ \ \. V \ / 7- t Ser. Chlorosperme.k. Fain. Confervem. PLATE LXXXVI. CLADOPHORA RUDOLPHIANA, mtz. Gen. Char. Filaments green, jointed, attached, uniform, branched. Fruit. aggregated granules or zoospores, contained in the joints, having, at some period, a proper ciliary motion. Cladophora (Kiitz.) — from xXaSof, a branch, and fope'o, to bear. Cladophora RudolpAiana; filaments very long, exceedingly slender, flex- uous, subgelatinoso-mcmbranaceous, much branched, brilliant, yellow- green, inextricable ; branches, di-trichotomous, or irregular ; ultimate ramuli pectinate, secund, very long and much attenuated ; articula- tions of the main filaments many times longer than broad, here and there swollen, their granular endochrome somewhat spiral; those of the ramuli 6-10 times as long as broad. Cladophora Rudolphiana, Kiitz. Pltyc. Gen. p. 268. Conferva Kudolphiana, Ag. in Bot. Zeit. vol.x. p. 636. /. Ag.Alg. Medit. p.12. Conferva Kaneana, Mc'Calla. Alg. Rib. no. 29. Hab. Parasitical on Zostera, the various Zaminarice and other sea plants, in 2-6 fathom water. Annual. Summer. Very abundant in Kound- stoue Bay, Cunnemara, Mr. Mc'Calla. Falmouth, Miss Warren. Geogr. Distr. Adriatic Sea, Agardh ! (v. in Herb. Hook.) Descr. Filaments exceedingly slender, forming very flaccid, subgelatinous tufts from six to twenty inches in length, excessively branched, and in most cases inextricably entangled. The branching appears to be an irregular combination of dichotomous, and alternate, with here and there some oppo- site branches ; and all the main divisions are either very flexuous or angu- larly bent. The ultimate ramuli are very long, attenuated to a fine point, and disposed in secund, subpectinate groups. Frequently one of the joints swells into an elliptical or spindle form, but without much apparent altera- tion in its nature. All the joints are of great length, as compared with their diameter, those of the main filaments being upwards of ten times longer than broad ; those of the ramuli from six to ten times. Their endo- chrome is lax, pellucid, and its granules are attached in subspiral lines to the walls of the cells. The colour is a rich glossy green ; the substance very soft ; and the whole plant adheres closely to paper in drying, and pre- serves its colour. One of the commonest sea plants in Roundstone Bay, Cunne- mara, where it infects every object on which it can lay hold, at a depth of from two to six fathoms, or perhaps more. It is very frequently found on the Laminar'ur, on Zostera, &c. Whilst young, and freely waving in the water, it is a very beautiful object ; but in age its tufts become drawn out to a great length, and its filaments twisted into green, mucous ropes, which stick to any object which comes near them. The botanist who dredges where this plant grows, however much he may admire it on the first few hauls, will soon wish that it was not quite so affec- tionate. In this country it was first noticed by Mr. Mc' Calla, who, observing that it was different from any British species, and believing it to be new, published specimens in his ' Algae Hiber- nicse,' under the name Conferva Kaneana, dedicating the species to Lady Kane, authoress of ' The Irish Flora,' who happened to be in the boat when the plant was discovered. I should have adopted this name had I not found, in Sir W. J. Hooker's rich Herbarium, a specimen of the C. BudolpMana, of Agardh, communicated by that author, which agrees in all essential par- ticulars with our Irish plant ; as does also the short description given by Agardh, in the ' Bot. Zeitung.'* Professor Kutzing, however, informs me that what he has received under the name C. BudolpMana, from Biassoletto, is a different plant, and that Agardh has distributed several different species under this name. This may possibly be so, yet I can hardly set aside the authority of the original specimen above mentioned; supported by the character — a very unusual one — of the occasional swelling of the joints, which I observed before I had seen Agardk's, C. Budol- pMana, or was aware what character he had assigned to it. Among British species, the nearest affinity of C. BodolpMana, is with C. gracilis, with which it agrees in the ramification, and in the great length of the alternate ramuli. But its filaments are very much more slender, its substance softer, and more flaccid, and its joints very much longer. The great length of the joints will also distinguish it from C. albida, which it likewise resembles. * C. Rudolphiana ; filis di-trichotomis ramosissiniis attenuatis mucosis, arti- culis diamctmm pluries superantibus, hie illic in globos elipticos inflatis. Ag. in Bot. Zeii. vol. x. p. 636. Eg. 1. Cladaphora Rudolphiana : — of the natural sice. 2. A portion of a branch. 3. A joint from the filaments. 4. One of the swollen joints : — all more or less magnified. Set. Melanosperji b e. P™- Sphaeelariea. Plate LXXXVII. SPHACELARIA PLUMOSA, Lpgb. Gen. Char. Filaments jointed, rigid, distichously branched, pinnated; rarely simple, or subdichotomous. Apices of the branches distended, membranous, containing a dark, granular mass. Fructification ; ellip- tical utricles, furnished with a limbus, borne on the ramuli. Spha- celaria {Li/ngb.),— from a^d«Xo S> gangrene, alluding to the withered tips of the branches. SpHACELARiAjotafwa: filaments naked at the base, elongated, irregularly branched, inarticulate ; branches pectinate-pinnate ; pinnae opposite, simple, very long and closely set. Sphacelaria plumosa, Lyngb. Fl. Ban. p. 103. t. 30. Ag. Syst. Alg. p. 166. Ag. Sp. Alg. vol. ii. p. 24. Grev. Fl. Edin. p. 313. Harv. in Hook. Brit. Fl. vol. ii. p. 324. Harv. in Mack. Fl. Hib. part Hi. p. 180. Harv. Man. p. 38. Wyatt, Alg. Banrn. no. 300. Endl. %rd Suppl. p. 23. Ch^etopteris plumosus, Kiitz. P/iyc. Gen. p. 293. Ceramium pennatura, Fl. Ban. t. 1481. Roth. Cat. Bot. vol. iii. p. 133. Ag. Syn. p. 68. Conferva pennata, Sm. E. Bot. t. 2330 {the left hand figure). Hab. On rocks, near low-water mark, and at a greater depth. Perennial. Beachy Head, Mr. Borrer. Frith of Forth, Sir J. Richardson and Dr. Greville. Wicklow, W.H.H. Belfast Bay, Mr. W. Thompson. Near Caernarvon, also at Dfracombe, and Land s end, Mr. Rolfs. Howth and Balbriggan, Miss Gower. Orkney, Rev. J. H. ~PoUexfi n. Kilbride, Major Martin. Geogr. Distr. German Ocean, along the shores of Denmark and Norway. Baltic Sea. Greenland, Fabrkius (see Lyngb.). Desck. Root minute, scutate. Fronds tufted, from two to four or six inches in length, setaceous, naked below, irregularly much branched above. Branches alternate or secund, or frequently fasciculate, several growing from the wounded apex of an older branch, one or two inches long, simple, erecto- patent, closely pectinate throughout their whole length with slender articu- lated ramuli. Ramuli patent, from one to three lines in length, opposite, issuing from every joint of the branches, parallel to each other, and of equal length, either quite simple or occasionally pectinato-pinnate in then- upper half. Apices of the branches frequently sphacelate. Main stem opake, not obviously jointed ; branches more translucent, jointed, the joints shorter than their breadth, longitudinally striate, and marked with a dark-coloured spot ; joints of the ramuli about once and a half as long as broad, similarly marked. Colour olivaceous, or occasionally rusty. Substance rigid, not adhering to paper in drying. By earlier writers this beautiful species was confounded with S. cirrhosa, of which it was considered to be a luxuriant variety, and in ' English Botany ' both are represented on the same plate. Mr. Borrer was, I believe, its first detector in this country, and I am indebted to him for one of the original specimens, gathered at Beachy head. From S. cirrhosa it may always be known, by the different structure of the stem, the closer and more regularly pectinated ramuli, and the greater size. S.plumosa appears to be peculiarly a northern plant, for though first observed on the south coast of England, it is by no means common there, nor are the specimens more than half the size of that represented in our plate. Further north, it is much more frequently met with, and becomes much more luxuriant. Our figure is taken from a Welsh specimen, and those collected by Sir. J. Richardson, at Colvend, in Dumfrieshire, are still more beautifully feathered with long ramuli. The Continental stations are all, it will be observed, from the north of Europe. I am not aware of its being found on the French coast. In substance and general habit, S. plumosa has very much the appearance of a Sertularia, and is almost as rigid. By Professor Kiitzing it is made the type of a separate genus, on account of the structure of its stem being a little different from that of the typical species ; but the difference does not appear to me to be sufficiently great to warrant the dismemberment of so natural a group, unless it were further borne out by a difference in fructi- fication. But the fructification of this, as well as of several others of the Sphacelaria, is unknown. Fucus rudis of Esper (Ic. Fuc. t. 27), which is said to be a native of the shores of England and France, is referred by Lyngbye to Sphacelaria plumosa, but if intended for this plant it is indeed a very rude representation of it. Esper's figure much more nearly resembles a faded piece of BalUa Brunonis, a native of the Southern Ocean ; but is said to have been drawn from a specimen received from Normandy. Fig. 1. Spiiacelakia plumosa : — of the natural size. 2. Segment of a branch. 3. Portion of one of the pectinate ramuli. 4. A cross section of the stem: — all more or leu highly magnified. i n * f « Ser. Rhodospekue.e. Fam. Nemastomea. PLATE LXXXVIII. CATENELLA OPUNTIA, Grev. Gen. Char. Frond dull-purple, membranaceous, filiform, constricted at intervals ; its axis composed of a lax net-work of anastomosing, lon- gitudinal filaments ; its periphery of densely compacted, dichotomous, inoniliform filaments. Fructification of two kinds, on distinct indivi- duals; 1, spherical masses of spores (favellldia) , contained in external capsular bodies (abortive ramuli, resembling ceramidla) ; 2, solitary oblong, transversely parted tetraspores, surrounded with a Kmbus, and formed from the filaments of the periphery, in which they are im- mersed. Catenella (Grev.), — a little chain, "in allusion to the chain, or necklace-like form of the frond." Catenella opuntia ; fronds rising from a mass of creeping fibres, vaguely branched ; pseudo-articulations lanceolate or elliptical, about four times as long as broad. Catenella opuntia, Grev. Alg. Brit. p. 166. t. 17. Rook. Br. Ft. vol. ii. p. 309. Han. in Mack. Ft. Hib. part 3. p. 188. Han. Man. p. 51. U'yatt, Alg. Damn. no. 126. /. Ag. Alg. Medit. p. 89. Endl. 3rd Suppl. p. 37. Kiitz. Phyc. Gen. p. 39-1. t. 76. f. 4. Chordaria opuntia, Spreng. Syst. Veg. vol. iv. p. 330. Lomextaria opuntia, Gaill. Diet. Hist. Nat. v. 53. p. 367. Halymenia ? opuntia, Ag. Sp. Alg. vol. i. p. 217. Syst. p. 245. Choxdria opuntia, Hook. Fl. Scot, part 2. p. 106. Grev. Fl. Edin. p. 292. Gigartixa opuntia, Laviour. Ess. p. 49. Gigartina pilosa, Lamour. 1. c. p. 49 (see Ag.). Rivularia opuutia, Gm. Eng. Bot. t. 1868. FUCDS opuntia, Good, and Woodw. in Linn. Trans, vol. iii. p. 219. Stack. Ner. Brit. p. 104. t. 16. Turn. Syn. Fuc. vol. ii. p. 387. Turn. Hist. t. 107. Fuccs repens, Light/. Fl. Scot. vol. ii. p. 961. With. vol. iv. p. 91. Flcus crespitosus, Stack. Ner. Brit. p. 59. t. 12. Ulva articulata /3. Huds. Fl. Angl. p. 569. Hab. On submarine rocks, piles, &:c, near high-water mark. Perennial. Not uncommon on the shores of England, Ireland, Scotland, and the Orkney Islands. Rarely found in fruit. Geogr. Distr. Atlantic shores of France and Spain. Mediterranean Sea. New Zealand, Dr. Hooker. Descr. Root, a mass of creeping, irregularly branched fibres. Fronds springing from the creeping fibres, erect, densely tufted, and forming patches two or more inches in diameter, spreading over any substance which they en- counter, half an inch to nearly an inch in height, sparingly branched, con- stricted at intervals into a string of oblong or lanceolate pseudo-articulations. Branches similar to the main stem, alternate or opposite, simple or forked, their terminal joints acute. Substanco membranaceous. Structure; the 2 Y central portion of the frond is filled with a watery mucus through which run longitudinal jointed fibres, with a narrow, coloured endrochrome and a wide pellucid limbus, anastomosing together into a lax net-work, with large, oblong subhexagonal meshes ; these constitute the axis : the periphery or outer wall of the frond is formed of very delicate, closely packed, horizontal dichotomous, momliform filaments, which spring from the most exterior of the fibres of the net-work, and their apices, closely glued together, unite into the membranous coat of the frond. Fructification j 1, spherical masses of spores or faeellidia contained in ovate capsules, furnished with a terminal pore, their walls formed of niouiliform filaments. The mass of spores appears to be formed bv a transformation of the internal net-work. 2. Oblong tetratpores divided at maturity by three transverse Hues, formed from the filaments of the periphery, and scattered at intervals among them. Colour a dull purple. This curious little plant appears to have been first noticed by Dillenius, in whose Herbarium specimens are preserved, ac- cording to Mr. Turner ; and was next excellently described by Lightfoot, who remarks that its branches resemble " the jointed leaves of the Cactus opuntia" a resemblance which has suggested the specific name, by which it has since been universally distin- guished. Lightfoot's trivial name " repens " has, however, the priority : though no one has adopted it. Its generic relations were, as appears by the numerous syno- uymes, long imperfectly understood, and few Algae have been more tossed about from one group to another, until, in 1830, Dr. Greville proposed it as the type of a new genus, in which step he has since been gladly followed by every succeeding author. His judgment was formed solely from consideration of the struc- ture of the frond ; the fructification being unknown to him. The tetraspores were first described, so far as I am aware, by Prof. .1 . Agardh, m his ' Algae 'Mcditerraneae,' his specimens having been received from Professor Meneghini, and they have been excellently figured by Kiitzing, in his great work. In this country both kinds of fruit were discovered by Mrs. Griffiths, to whose kindness I am indebted for all the specimens I have seen. C. opuntia can only be confounded with a dwarf state of Chylocladia articvlata, which is about the same size. But, not to speak of difference of structure, the brighter colour, cylindrical joints, delicate substance, acute angles, and forked fronds of the latter, sufficiently distinguish it. Pig, i. (' vhaki. la opuntia : — qf the natural size. Z.Fronds. 8. A joint bearing & ceraviidwm. I. Ceramidium cut open. 5. Spores, from the same. 6. Longitudinal section of the Frond. 7. Transverse semi-section, with tetras- pores in titu. B A tetraspore: — all mare or less highly magnified. Scr. MelanospermejE. Fain. Facea. Plate LXXXIX. . PYCNOPHYCUS TUBERCULATUS, Est*. Gen. Char. Boot composed of branching fibres. Frond cylindrical, diclio- tomous. Air-vessels, when present, innate, simple. Receptacles ter- minal, cellular, pierced by numerous pores, which, communicate with immersed, spherical conceptacles, containing, in the lower part of the receptacles, parietal, simple spores, and in the upper, tufted antheridia. Pycnophycus (Kilt;.), — from ttvkvos, thick, and vvf}os,j)urjj/r. Porphyra laciniata; frond deeply and irregularly cleft into several broad segments. Porphyra laciniata, Ag. Syst. p. 190. Ag. Ic. Alg. Eur. t. 26, 27. Grev A/,/. Brit. p. 16S. Hook. Br. Ft. vol. ii. p. 310. Hurt, in Mack. Fl. Mb. part 3. p. 241. Han. Man. p. 169. Wyatt, Atg. Damn. no. 32. F.mtl. 3rd Suppt. p. 19. Kiitz. Phyc. Gen. p. 383. Porphyra umbilicatis, Kiitz. Phyc. Gen. p. 383. Ulva laciniata, Light/. Fl. Scot. p. 974.. t. 33. Roth, Fl. Germ., p. 585. Ag. Sp. Alg. vol. i. p. 404. Ulva umbiliealis, E. Bot. t. 2286. Lyngb. Hyd. Dan. p. 28. Hab. On marine rocks, within the range of the tide. Annual. Spring to autumn. Abundant on all our shores. Geogr. Distr. Throughout the Atlantic Ocean, from the Fceroe Islands to the Cape of Good Hope. Descr. Root, a minute disc. Fronds two to eight inches long, clustered toge- ther, expanded, delicately membranaceous, pellucid, very irregularly divided into several lobes ; the point of attachment frequently within the frond, which is then peltate. Margin wavy, entire or irregularly cut ; apices often truncate. Under the microscope the whole frond appears to be divided mto squares, in the manner of a tessellated pavement, and within each square are four purple granules, or spores, which constitute the fructification and the whole colouring matter of the frond. When not in a state of perfect fructification the colour is much less bright, tending to a livid olive. Besides the usual fructification, Dr. Greville describes a second, consisting of " sori of smaller ovate granules scattered without order chiefly towards the mar- gins of the frond." These I am not acquainted with. In drying, the colour becomes much brighter ; but the glossy and delicate fronds do not adhere closely to paper, and shrink very much. This very common plant is found in most parts of the Ocean throughout the tropics, and exists nearly as far as vegetation extends towards the poles. It varies in different places, some- thing in substance, being thicker or thinner; something in colour, being sometimes of a bright purple, and sometimes much tinged with olivaceous green ; and something in form, some indi- 2a2 viduals having a flat lobed frond, and others a cup -shaped frond fixed by a central point. But all its forms are easily recognized, and may be traced by insensible gradations, one into the other. The genus Porphjra is anomalous among the Chlorosperms, having the colour of the more perfectly organized Bhodosperms. From these latter it differs in its diffused fructification, and in this respect perfectly agrees with the TJlvacea, among which it is placed. This species, together with the closely allied P. vulgaris, is sometimes brought to table in England under the name of Laver ; and in Scotland and Ireland under that of Sloke, Slov.fr, or Sloukawn. After many hours boiling the frond is reduced to a somewhat slimy pulp, of a dark brown colour, which is eaten with pepper and lemon-juice or vinegar, and has an agreeable flavour to those who have once conquered the repugnance to taste it, which its great ugliness induces, and many persons are very fond of it. It might become a valuable article of diet, in the absence of other vegetables, to the crews of our whaling vessels cruising in high latitudes, where every marine rock, at half-tide, abundantly produces it. In its prepared state it may be pre- served for an indefinite time in closed tin-vessels. Fig. 1. Porphyra laciniata : — of the natural size. 2. Small portion of the frond, showing the quaternate granules : — magnified. y— ^ * ' Ser. Chlorospeume*. Pam. SipAonetz. PLATE XCIII. CODIUM TOMENTOSUM, Stack. Gen. Char. Frond green, sponge-like (globular, cylindrical or flat ; simple or branched), composed of tubular, interwoven, inarticulate filaments (elongated, branching cells). Fructification; opake vesicles [conio- cystce) attached to the filaments. Codium {Stack.), — from k&jSioi/, t/ie skin of an animal. Codium tomentosum ; frond linear, dichotomous, cylindrical or compressed. Codium tomentosum, Stack. Ag. Sp. Jiff. vol. i. p. 452, Ag. Syst. p. 177. Spreng. Syst. Veg. vol. iv. p. 365. Grev. Alg. Brit. p. 185. t. 19. Hook. Brit. Fl, vol. ii. p. 318. Han. in Mack. Fl. Hib. part 3. p. 232. Han. Man. p. 145. Wyatt, Alg. Damn. no. 35. /. Ag. Alg. Medit. p. 23. Midi. 3rd Suppl. p. 21. Kiitz. P/tyc. Gen. p. 309. t. 42. f. 1. Monty. Canar. Crypt, p. 182. Pol. Leed. p. 35, Alger, p. 48. Codium elongatum, Ag. Sp. Alg. vol. i. p. 454. Ag. Syst. p. 177. Endl. Zrd Suppl. p. 21. Montg. Alger, p. 50. 1. 13. f. 1. Codium lineare ? Ag. I. c. Codium filiforme? Montg. Alger, p. 50. t. 10. f. 2. Spongodium tomentosum, Lamour. Ess. p. 73. Spongodium commune, Bory, Ditp. Voy. Bot. p. 210. Fucus tomentosus, Huds. Fl. Aug. p. 514. Slack. Ner. Brit. t. 7. Good. and Woodio. in Linn. Trans, vol. iii. p. 195. E. Bot. t. 712. Esper, Fuc. t. 112. Turn. Syn. vol. ii. p. 300. Hist. t. 135. Agakdhia diehotoma, areolata, et rameutacea, Cabrera, in Phys. Sdlhk. Arsber. Hab. On rocks in the sea, within the range of the tide; generally near low -water mark. Perennial. Summer. Common on the rocky shores of the British Islands. Geogr. Distr. Common on all the shores of Europe, both Mediterranean and Atlantic. Dispersed also throughout the temperate and torrid portions of the Atlantic, Pacific, and Indian Oceans. New Holland and Tasmania. Auckland Islands. Descr. Fronds rising from an expanded velvety incrustation, which forms wide patches on the surface of rocks, solitary, or gregarious, from six inches to two feet in length, from two to four lines in diameter at the base, erect, more or less regularly dichotomous, with or without lateral ramuli. Branches cylindrical or frequently compressed, linear, obtuse, often expanded, sometimes greatly so, beneath the forkings. Axils rounded. The whole frond is coated with delicate, hyaline, horizontal filaments, one or two hues in length, and of a very soft and gelatinous substance. Structure ; the axis is composed of innumerable, interwoven, irregularly branched, slender filaments, from which issue radiating, horizontal, somewhat clavate ramuli, whose apices constitute the surface of the frond. To the sides of these ramuli are attached the ovato-lanceolate subsessile coniocystte, which contain at maturity, an oval, transversely striate, dark green mass, which is even- tually discharged through a terminal pore. At plate XXXV, I figured two of the more minute species of Codium ■* I here present one which is of larger size, more gene- rally known, and the most widely dispersed of the genus. It occurs throughout the Pacific Ocean from the shores of Arctic America and Asia, to the southern extremity of America ; and is equally dispersed throughout the Atlantic. In general features, specimens from most countries agree, but there are slight points of difference, on which authors have founded species, which I can- not but regard as mere varieties of a common type. Such is the C. elongatwm of Agardh, an admirable figure of which is given in the splendid 'History of Algiers,' now publishing under the auspices of the French Government. This form, which accom- panies the common C. tomentosum on the West coast of Ireland, is chiefly remarkable for a great dilatation of the frond imme- diately under the forking of the branches. This enlargement certainly gives the specimens a distinct look, but traces of it may be found in various degrees of development, inseparably con- necting the most dissimilar looking individuals of C. elongatwm., with the common dichotomous, filiform C. tomentosum. Were G. elongatum admitted as a species, several other forms might be enobled on grounds as valid. There is, for instance, a common state of this plant, which is very irregularly divided, having the branches set with numerous lateral branchlets half an inch to an inch long, which is as abnormal as C. elongatum. Codium tomentosum has to the naked eye quite the appearance, though not the substance or structure, of a sponge ; and, indeed very closely resembles in form and colour the Spongia hisjnda, Mont., offering a beautiful instance of analog g between organisms whose affinity is widely separated. * To the habitats given under PL XXXY. for C. adherens add Kathlin Island, Antrim, Mr. B. Moore, aud Tory Island, Mr. G. Jlyndman. Mr. Moore's spe- cimens were gathered in 1834, and to him, therefore, the credit of being the discoverer of this plant in Ireland belongs. Fig. 1. Codium tomentosum :—of the natural size. 2. Filaments of the periphery, with fruit : — highly magnified. Ser. Rhodospermeje. Fain. Plate XCIV. FURCELLARIA FASTIGIATA, Lamour. Gen. Char. Root brandling. Frond cylindrical, dichotomous, cartilagi- nous, solid; the axis consisting of densely packed, longitudinal, interlacing and anastomosing filaments; the periphery of coloured, horizontal, dichotomous filaments, issuing from those of the axis, whose lower half is composed of large, elliptical cells j their apices of much smaller cylindrical cellules. Fructification, " terminal, elon- gated, pod-like receptacles, containing a stratum of dark, oblong, pear-shaped spores in the circumference" (Grev.). Furcellaria {Lamour.), — from furcula or furcilla, a little fork; alluding to the forked frond. Furcellaria y*?;%2ate. Furcellaria fastigiata, Lamour. Ess. p. 26. Ag. Sp. Alg. vol. i. p. 103. Ag. Sgst. p. 274. Grev. Fl. Edin. p. 286. Grev. Alg. Brit. p. 67. t. 11. Hook. Brit. Fl. vol. ii. p. 283. Wyatt, Alg. Damn. no. 100. Ban. in Mack. Fl. Hib. part 3. p. 190. Harv. Man. p. 54. End/. 3rd Suppl. p. 38. Kiitz. Fliyc. Gen. p. 402. t. 71. Furcellaria lumbricalis, Lamour. Ess. p. 26. Lyngb. Hyd. Dan. r>. 48. t. 40. Hook. Fl. Scot, part 2. p. 97. Spreng. Syst. Veg. vol. iv. p. 3*15. Fucus fastigiatus, Euds. Fl. Aug. p. 588. Light/. Fl. Scot. p. 930. Gm. Hist. p. 108. t. 6. f. 1. Good, and Woodw. in Linn. Trans, vol. iii. p. 199. Stack. Ner. Brit. t. 6 and 14. Fl. Dan. t. 393. Fucus lumbricalis, Gm. Hist. p. 108. t. 6. f. 2. Good, and Woodw. in Linn. Trans, vol. iii. p. 204. Turn. Syn. p. 317. Hist. t. 6. E. Bot. t. 824. Fucus furcellatus, Linn. Sp. PI. p. 1631. Huds. Fl. Aug. p. 589. Hab. On submarine rocks, within tide marks, generally growing in tidal pools. Perennial. Winter. Common on the shores of the British Islands. Geogr. Distr. Northern Ocean. Atlantic shores of Em-ope, and of North America. Descr. Moot composed of entangled, branching fibres. Fronds densely tufted, from four to eight inches in height, half a Hue to a fine in diameter,' filiform, cybndrical, rising with a simple stem for two to three inches, forked, and afterwards repeatedly dichotomous, with acute angles ; all the tops of equal length. The tips of the branches are either much lengthened into what appear like lanceolate receptacles or pods, simple or forked, one to two inches long, and tapering to a fine point, which fall away at maturity ; or, on different individuals, the truncated apices produce by a second orowth, slender, forked ramuli, terminating in ovate, pale-coloured pod-like bodies, half an inch in length, and either simple or forked. The elongated pod-like apices are usually regarded as the fructification, and their falling away at stated periods favours the conjecture ; but their structure is similar to that of other parts of the frond, except that the stratum of elongated con- centric dark-coloured cells, which are usually regarded as the spores, and which exist in all parts of the frond, are rather more developed. These are, however, very unlike tetraspores. Colour dark brownish red. Substance There is such a strong external resemblance between the sub- ject of this plate, and that of the following one {Polpdes rotun- dus), that they are often mistaken one for the other, and without contrasting the fibrous root of the former, with the large scutate base of the latter, it might, in some instances, be difficult to discriminate between them. There is, indeed, some difference in the structure of the frond, but not of a very striking character, and though easily observed when slices of both are seen together under the microscope, most difficult of being defined in intel- ligible words. And yet, with this resemblance in general ap- pearance, all modern authors, with the exception of Kiitzing, place them in different genera ; and, until very lately, even in different families. This opinion of botanists is grounded on a great difference observed between the fructification of these plants ; and is probably correct. But the fructification of Fur- cellaria is very imperfectly known, or if known, is of such an anomalous character that it is difficult to build upon it, The pod-like elongations of the branches, which are produced in winter, and drop off as the season advances, do indeed appear like fructification, and are so described by authors. But their structure is widely different from that of the fruit of other R/to- dosperms ; and if they be entitled to the name of fruit, it must be of the conceptacular kind, for the spores which they contain in no respect resemble tetraspores. If my dissections be correct, they differ from other cellules only by being of a darker colour. They occupy no isolated portion of the frond, but are found, though of smaller size, in all its parts, extending in a stratum between the external and internal filaments of the periphery, between which they are the connecting links ; being attached to both by one or other extremity. I shall be very glad of further information on the fructification of this plant, should any observer have detected tetraspores. Yi". 1. Furcellaria fastigiata. 2. Portion of a frond with inflated tips: ° —both of the natural she. 3. A transverse, and 4, a longitudinal section of a "receptacle " : — both highly magnified. % t*« v I ; s w * Ser. Khodospermfje. Fam. .Spo/igioearpea. Plate XCV. POLYIDES ROTUNDUS, Oreo. Gen. Char. Root an expanded disc. Frond cylindrical, dichotomous, car- tilaginous, solid, the axis consisting of densely packed, longitudinal, interlacing and anastomosing nlaments; the periphery of coloured, horizontal, dichotomous nlaments, whose lower half is composed of large, elliptical cells; their upper of much smaller, submoniliform cellules. Fructijieation, of two kinds, on distinct individuals ; 1, oblong, irregularly formed, external warts, composed of dichotomous filaments, through which are scattered elliptical favella, having a broad pellucid limbus. 2, cruciate tetraspores immersed, at intervals, among the filaments of the periphery. Polyides (Ag.), — from vdKv, many, and ISea, form or appearance ; a name ill applied to the present genus. Polyides rotundus. Polyides rotundus, Grev. Alg. Brit. p. 70. 1. 11. Hook. Brit. Fl. vol. ii. p. 884. Wyatt, Alg. Banm. no. 161. Earn, in Mack. Fl. Hii>. part 3. p. 190. Han. Man. p. 43. Polyides lumbricalis, Ag. Sp. Alg. vol. ii. p. 392. Ag. Syst. Alg. p. 194. Spreng. Syst. Feg. vol. iv. p. 344. Endl. 3rd Suppl. p. 38. Spoxgiocarpus rotundus, Grev. Fl. Edin. p. 286. Fcrcellaria rotunda, Lyngb. Hyd. Ban. p. 49. Flrcellaria lumbricalis, Kid;. P/tyc. Gen. p. 402. t. 72. Chordaria rotunda, Hook. Fl. Scot, part 2. p. 97. Gigartisa rotunda, Lamonr. Ess. p. 49. Fucus rotundus, Gm. Hist. p. 110. t. 6. f. 3. (excl. syn. Huds. and Rail.) Linn. Syst. Nat. Gm. p. 1383. With. vol. iv. p. 110. Turn. Syn. Fuc. vol. ii. p. 309. Turn. Hist. t. 5. E. Bot. t. 1738. Fuccs radiatus, Good, and Woodw. in Linn. Trans, vol. iii. p. 202. Stack. Ner. Brit. p. 89. 1. 14. Fucus caprinus, Gunn. Fl. Xorv. vol. i. p. 96. Fccus fastigiatus, Herb. Linn. (sec. Turn.) Esper, t. 16 (excl. syn.). Hab. On rocks in pools, within the tide range. Perennial. Whiter. Frequent on the shores of England and Ireland. Jersey, Miss White and Miss Turner. Pare in Scotland? Appin, Capt. Carmiehael. Dumfries, Sir J. Richardson. Frith of Forth, Mr. Maughan, Mr. Stewart, Dr. GreriUe. Aberdeen, Dr. Dickie. Orkney, Rev. Mr. Clouston, Rev. Mr. Follexfen, Lieut. Thomas, Dr. Mc'Bain. Ardros- san, Major Martin, and Rev. D. Landsborough. Geogr. Distr. Atlantic shores of Europe from Iceland to France (and Spain?). Atlantic shores of North America. Boston, Mr. Emerson. New York, Prof. Bailey. Adriatic Sea, IF, id/en (omitted by J. Agardh). Descr. Root a fleshy, flattened, circular disc, half an inch or more in diameter. Fronds densely tufted, from four to eight inches high, as thick as a crow s quill, cylindrical, rising with a simple stem from one to three inches in length, then forked, and afterwards repeatedly and closely dichotomous ; the axils rounded. Apices of equal length Fructification, of two kinds on distinct plants ; 1, fleshy warts of a pale pinky colour, from a quarter to half an inch in length, bursting out irregularly from various parts of the branches, composed of vertical, dichotomous, moniliform, slender filaments, among which are thickly scattered large, oval faveUa, containing a densely compacted cluster of conical spores. 2, oblong tetraspores, divided cross- wise, scattered at intervals among the filaments of the periphery of the frond, through all the upper branches of plants which produce them, vertical, deeply sunk. Colour a dark brownish red. Substance cartilaginous. The genus Polyides is remarkable for its singular fructification, which strikingly differs both in appearance and structure from that of any other of the Bhodospermece. In appearance the con- ceptacular fruit most nearly resembles what are called nemathecia, but the distinct and isolated favellm which it contains are very different from the contents of those imperfectly organized excres- cences. Here, in what look like irregular warts, we have most perfectly formed and symmetrically arranged spores. The tetra- spores, which are now, I believe, described for the first time, were . discovered by Mrs. Griffiths, whose researches into the fructifi- cation of the Algae are beyond all praise, and to her I am in- debted for specimens, producing this description of fruit. It is found in winter, but on plants which do not form warts. Poli/ides rotundus has a wide range in the northern hemi- sphere, being found through most of the cold and temperate lati- tudes of the Atlantic. It is perhaps the only species of the genus ; the P. D' Urvillai of Bory being a doubtful species, very possibly not a congener. I follow Greville in retaining the specific name adopted in the great work of Turner, the foundation of modem Phycology, in place of that selected by Agardh from Bauhin's ' Pinax ', though to the latter the mere priority may belong. The truth is, that the strong resemblance between Polyides rotundus and Furcellaria fastigiata {Fucus hmbricalis, Gm.), has caused their synonymy to be so confused in the works of early writers, that it is a ques- tion to which of them Bauhin applied the name hmbricalis. Even Linnaeus confounded one with the other. 1 POLYIDES rotundus :— qf the natural nee. 2. Transverse section ol the frond, and of a wart. 3. A favella. i. A spore from the same. 5. One (.1 the filaments of which the wart is composed. 6. Transverse section of a frond, with tetraspores. 1. Tetraspores :— all wore or less highly magnified. mil' Hill' I'.li Hill. E , a:,; Si;; v. •■in Jllji K I •K? W'V > s III.*" ifti 1 "III Hi III •••*' % »•■•■ 111 'i'."'.' f Eg I sc Kv.v p "hi. § I %■■*■•' ;> v.v. life ll * £ it ••'ill ,Jtr •,. - #4 Ser. Chlorospekme^. Fam. Ulvacea ? Plate XCVI. BANG I A FUSCO-PURPUREA, L m b. Gen.Cii.u;. Frond filiform, tubular, composed of numerous radiating cel- lules, disposed in transverse rows, and enclosed within a liyaline conti- nuous sheath. Spores purple or green, formed within each of the cells of the frond. Bangia {Lyngb.),—m honour of Eofmann Bang, a Danish botanist, and friend of Lyngbye. Bangia fiusco-pitrpwea ; filaments elongated, simple, decumbent, nearly straight, here and there constricted, forming a brownish-purple, glossy stratum ; granules several in each transverse band, dark purple. Bangia fusco-purpurea, Lyngb. Hyd. Dan. p. 83. t. 2-1. Grev. Fl. Edin. p. 302. Spreng. Sy*l. Veg. vol. iv. p. 361. Grev. Alg. Brit. p. 177. Hook. Brit. 11. vol. ii. p. 316. Wyatt, Alg. Damn, no. 167. Hare, in Mack. Fl. Hib. part iii. p. 341. Man. Man. p. 172. /. Ag. Alg. Medit. p. 14. Kiitz. Fhyc. Gen. p. 249. Cliauv. Mem. sur Bangia, Reckerches, p. 35. Bangia utro-purpurea, Ag. Sysl. p. 76. Ag. Ic. Alg. Eur. t. 25. Endl. Zrd Suppl. p. IS. KM:. Phyc. Gen. p. 250. Bangia versicolor, Kiitz. 1. c. p. 250. t. 45. f. 3. Conferva fusco-purpurea, Billw. Con/, t. 92. E. Bot. t. 2055. Conferva atro-purpurea, Roth. Cat. Bot. vol. iii. p. 20S. t. 6. Billw. Conf. 1. 103. E.Bot. t. 2085. Hab. On rocks and planks in the sea, within the tide range (also in fresh- water rivers and canals). Common on the shores tf England and Ireland, in many places. Rare in Scotland ? Frith of Forth, Prof. Arnott. Jersey, Mm White. Geogr. Distr. Atlantic Shores of Europe, from the Foeroe Islands to France. Mediterranean Sea. Descr. Fronds fixed by their base, aggregated into widely spreading patches, several inches in diameter, capillary, from one to three or four inches in length, decumbent, or floating hi the water, very flaccid, glossy and lubri- cous, some of the threads of much greater thickness than others. Threads cylindrical, composed of radiating, obconieal cellules disposed in circles round a narrow central tube, and contained within a pellucid sheath ; these circles of cells, closely piled on each other, constitute the frond. Each cell contains a dark purple mass of endrochome, which finally is compacted into a spore, and discharged, on the rupture of the parent cell, into the tube. The genus Bangia, founded by Lyngbye, in honour of his friend and preceptor in Phycological studies, has, owing to its originally vague definition, been more than usually unfortunate in having intrusive species placed in it ; as well as having a great 9 w 9 A a r~ variety of characters assigned to it by the several authors who have taken it up. Even those who agree iu making B. fusco- purpurea the typical species, describe its structure very diffe- rently ; some asserting that this plant is flat, others tubular but piano-compressed, and others cylindrical. That the latter is its true character becomes at once evident, by making a transverse section of a filament, or, as is much more easily done, by cutting a half dry bundle of filaments into short frustules, which, when moistened, will immediately exhibit the circular wheel-like ap- pearance, represented at our fig. 3. M. Chauvin, in his excellent ' Recherches '*, has entered at great length into the history of this genus, proposed a reformed character, and limited the species to B.fHsco-purpurea (the type), B. crispa, B. ciliaris, and B. elegans, Chauv., the last-mentioned differing from the others in having a branching frond. B. LaminaricB of Lyngbye, is, he assures us, identical with the young state Jsperococcus ? pmilli/s, Cann., its affinity with which was long since pointed out by Mr. D. Moore. While I admit the near proximity of these plants, I am not yet prepared to unite them. B ? Icetevirens, on the same authority, is only the rudimentary state of an Enteromorpha ; and this I am disposed to allow. A curious point in the history of Ban/jia fusco-purpurea is, that it is found equally in the sea, and in fresh-water rivers and canals, reaching an equal degree of development and coloration in either situation. Such an indifference is very unusual among the Algae ; but I can perceive no sufficient distinctions between the fresh-water and marine specimens to found a separate species upon. Prof. Kiitzing, however, describes the fresh-water form under two names, B. coccineo-purpurea and B. roseo-purpurea ; relying chiefly on the habitat, and some slight difference of colour. I fear these species cannot stand. * Recherches sur reorganization, la fructification et la classification dc plusicurs genres d'algues, &c. : Caen, 1842. Fig. 1. Bangia fusco-pukpurea : — of the natural size. 2. Portions of fila- ments : — magnified. 3. A transverse section of a filament : — highly magnified. Scr. Riiodosferme.«. Fain. Nemastomece. Plate XCVII. IRID^A EDULIS, Bory. Gen. Char. Frond flat, camoso-cartiraginous, dull red; the central sub- stance composed of densely interwoven, longitudinal fibres ; the peri- phery of closely packed, horizontal, moniliform filaments. Fructifica- tion of two kinds, on distinct individuals; 1, spherical masses of spores (favellidia) immersed in the frond ; 2, tetraspores forming a stratum at the base of the filaments of the periphery. Irid^a {Bory), — from iris, the rainbow; because some species reflect rainbow colours when growing imder water. Irid.ea edulis ; frond undivided, obovate, rounded at the apex, wedge- shaped at the base ; with a short stem. Irid/F.a edulis, Bory, in Diet. Class. d'Rist. Nat. vol. ix. p. IB. Grev. Alg. Brit. p. 158. 1. 17. Hook. Brit. Fl. vol. ii. p. 308. Wyatt, Jig. Danm. no. 78. Harv. in Mack. Fl. Hib. part. 3. p. 189. Earv. Man. p. 53. Midi. Zrd Suppl. p. 37. Kith. Phyc. Gen. p. 396. Halymenia edulis, Ay. Sp. Alg. vol. i. p. 202. Ag. Syst. p. 242. Hook. Fl. Scot, part 2. p. 107. Spreng. Syst. Veg. vol. iv. p. 333. Delesseria edulis, Lamour. Ess. p. 38. Ulva edulis, Decani. Fl. Fr. vol. ii. p. 12. Grev. Fl. Edin. p. 298. Fucus edulis, Stack. Ner. Brit. p. 57. t. 12. With. vol. iv. p. 101. Turn. Syn. vol. i. p. 180. Turn. Hist. 1. 114. E. Bot. 1. 1307. Hook, in Fl. Lond. cum icone. Fucus dulcis, Gm. Hist. Fucp. 189. t. 26 (the figure only ; tlte description belongs to F. palmata). Fucus lactuca, Esper, Ic. Fuc. vol. i. p. 129. t. 64. Fucus carnosus, Schmidel, It. p. 76. Esp. 1. c. p. 150. t. 76. Fucus palmatus, jS. Light/. Fl. Scot. p. 935. Hab. On marine rocks, near low-water mark. Perennial. Fruiting in winter. Frequent on the shores of the British Islands, from Orkney to Jersey. Geogr. Distr. Atlantic shores of Europe, from the shores of Iceland (Esper) to Spain (Ag.). Baltic Sea, Agardh, Aresch ! Mediterranean at Malaga,^/. Cape of Good Hope, according to a specimen in Herb. Paris, Ag. Descr. Root, an expanded callus. Fronds numerous from the same base, from six inches to a foot or more in length, and from two to sLx inches in breadth at the widest part, rising with a short, cylindrical stem, of a few lines in length, which becomes first compressed, then quite flat, and gra- dually expands into the cuneate base of a perfectly simple, obovate frond, which is very obtuse and rounded at the apex. It is subject to very little natural variation in form, except in being occasionally oblique, one side ex- panding more rapidly than the other ; but no plant is more subject to injury either from the attacks of marine animals, or laceration by the waves, and its froiids are usually much perforated, or split longitudinally ; the apices erose or laciniated. Fructification; 1, favellidia immersed beneath the periphery, densely scattered in the upper portion of the frond, appearing to the eye like minute dark red dots, composed of very densely packed, angular spores ; 2, tetraspores either triparted or cruciate, disposed in very dense band-like sori, the sorus lying beneath the filaments of the periphery, and extending across the upper portion of the frond. Colour a full dark blood-red ; becoming much darker in drying. Substance firmly cartilaginous, or somewhat fleshy. It is a singular, and almost an unaccountable fact, that this plant, than which none are more invariable in character, or more distinct in general appearance, should have been long confounded with Mhoclymenia palmata, a plant of a very different form, diffe- rent structure, and different substance. Withering was the first author who clearly defined the present ; but it is to be regretted that he assigned the specific name edulis to it, for though a favourite, certainly, with marine worms, it rarely constitutes a part of human food ; the B. palmata being the true eatable Fucus or Dulse of the Scotch and Irish. I have never seen I. edulis eaten, but Stackhouse tells us that in Cornwall it is some- times eaten by fishermen, who crisp it over the fire. The same author speaks of a fine ruby-coloured dye being extracted from it by simple maceration. Similar dyes exist in a great number of Algse, but I should fear that they would not prove of a very permanent character. The genus Iridcea is widely dispersed over the world, the maximum of the species being in the Pacific and Southern Oceans. Many of them are of very large size, and almost all, are exces- sively variable in form. Several of Bory's species have now been properly moved by Prof. J. Agardh, to the genus Gigartina, namely, /. radula, striata, papillora, and their alhes. Fig. 1. Ikicea edulis: — of the natural size. 2. Section of a frond producing favellidia. 3. Section of a frond producing tetraspores. i. Tetraspores separated : — all magnified. I Ser. Melanosperjie.e. Fam. Chordariea ? Plate XCVIII. RALFSIA DEUSTA, Berk. Gen. Chaji. Frond coriaceo-crustaceous, fixed by its inferior surface, orbi- cular, concentrically zoned; composed of densely packed, vertical, simple filaments. Fructification ; depressed warts, scattered over the upper surface, containing obovate spores fixed to the bases of vertical filaments. Ealfsia {Berk.), — in honour of John Ralfs, Esq., of Penzance, a most acute and accurate botanist, whose discoveries among the minute Algae, especially the Diatomacece , have thrown great light on that little known branch of botany. Ealfsia deusta. in-FSiA deusta, Berk, in Eng. Bot. Suppl. t. 2866. Hildenbrandtia rubra, Endl. 3rd Suppl. p. 26 {nee. syn. Berk.; nee. Menegh.). Cruoeia verrucosa, Aresch. Padina? deusta, Hook. Br. Tl. vol. ii. p. 281. Ran. in Mack. Fl. Hid. part 3. p. 178. Han. Man. p. 31. Zonaria? deusta, Ag. Syn. p. 40. Ag. Sp. Alg. vol. i. p. 132. Ag. Syst. p. 265. Lyngb. Hyd. Ban. p. 19. t. 5. Fucus fungularis, Oeder. Fl. Norv. vol. ii. p. 107. Fl. Ban. t. 420 (excl. mmTlmperati.). Hab. Common on the rocky shores of the British Islands, between high- water mark, and half-tide level ; from Orkney to Devonshire. Peren- nial. Winter. Geogr. Distr. Atlantic shores of Europe from Iceland to France. Baltic Sea, Aresch. Kamtschatka and Unalasclia, Tilesius. Descr. Fronds spreading over the surface of rocks in crustaceous, lichenoid patches, from one to sis or more inches in diameter ; when young, orbicular, but becoming very irregular in outline when old, marked, more or less evi- dently, especially towards the margin, with concentric striae or bands, about a lin e asunder. The surface of the frond in young specimens is nearly flat and even, but in full grown individuals it is much corrugated, and covered more or less with wart-like prominences ; and very old plants present an exceedingly rugged surface, in which all traces of concentric striae are lost. The structure of the frond is very dense and opake, but thin, vertical slices exhibit an arrangement of the cellules into vertical closly packed filaments, strongly glued together. The fructification consists of scattered warts, com- posed of vertical, easily separable filaments, to whose bases are attached obovate, simple spores. Colour a dark, coffee-brown, becoming darker in drying. Substance between leather}' and crustaceous, flexible. This singular production more nearly resembles, to the naked eye, a crastaceous Lichen, than an Alga, but its structure and fructification prove it to be widely different from any Lichen. There is a curiously close resemblance, both in the habit, the structure of the frond, and the outward character of its fruit, between Ralfsia and Pcysonellia ; yet, according to the received notions of arrangement, these plants must be referred to opposite parts of the system. They are, however, closely analogical forms, in the families to which they respectively belong. Except for the colour, and the different formation of the spores, there would be little to distinguished them. Ralfsia deusta is a very common species throughout the Northern Atlantic Ocean, and probably extends along most of the shores of Europe, North Asia, and North America ; though not yet recorded from the latter. Its crastaceous habit may often cause it to be over-looked. Endlicher has confounded it with the very different Hilden- brandiia rubra (which is also common on the British coast); and Areschoug has, still more unhappily, put it into the same genus as Cruoria pellita, with which, in structure, it has very little connection. The resemblance between these is purely external. The fructification of Ralfsia is either very rarely produced, or so difficult to find, owing to its obscurity, that it is rarely seen. It was first observed, I believe, by Dr. Johnston, who commu- nicated the specimens to Mr. Berkeley, by whom they were des- cribed. Though myself familiar with this plant for many years, I had never seen the fruit, until I received fertile specimens from Dr. Dickie of Aberdeen, and from these I have made my analysis. On the west coast of Scotland and of Ireland this plant is exces- sively abundant, and its patches reach a large size. Devonshire specimens, communicated by the Rev. Mr. Cresswell, are much inferior. Fig. 1. Ralfsia deusta, young and old fronds : — of the natural size. 2. Ver- tical section of the frond. 8. Filaments of which the frond is composed. 4. Spores, among the filaments of a wart. 5. A spore and its filaments, separated : — all more or less highly magnified. i l\ I I I \ w ! ! -**fe Ser. Chlorosperme.e. Fam. Confervem. Plate XCIX. A. CONFERVA MELAGONIUM, Web.etMohr. Gen. Char. Filaments green, jointed, attached or floating, unbranched. Fruit, aggregated granules or zoospores, contained in the joints, having at some period, a proper ciliary motion. Conferva (Plin.) — from conferruminare, to consolidate ; because some of the species were used bv the ancients in cases of fractured bones. Conferva Melagonium ; root scutate, filaments elongated, robust, scattered or slightly tufted, erect, stiff and wiry, dark-green ; joints twice as long as broad. Conferva Melagonium, JJ'eb. el Mohr. It. Suec. p. 194. t. 3. f. 2. a, b. Roth, Oat. Bot. vol. iii. p. 254. Dillic. hit. p. 48. Suppl. t. B. Ag. Syn. p. i t. Lyngb. Hyd. Dun. p. 148. t. 51. Ag. Syst. p. 99. Han. in Hook. Br. Ft. vol. ii. p. 354. Han. in Mack. Fl, Hib. part 3. p. 226. Han. Man. p. 130. Wyatt, Alg. Damn. no. 221. Kiitz. Phyc. Gen. p. 260. Hab. On the rocky bottoms of deep tide pools, near low-water mark. Perennial. Pound on many parts of the British coasts, from Orkney to Cornwall, and on all the coasts of Ireland ; but nowhere very abun- dant. Jersey, Miss White. Geogr. Distr. Throughout the Northern and German Ocean. Iceland. Green- land. Shores of North America ; Boston Bay, Dr. A. Gray. Descu. Boot scutate. Filaments five to twelve inches long or more, twice or thrice as thick as hog's bristles, erect, stiff, and very tough, straight, ot equal diameter throughout, rarely tufted, generally growing in a scattered manner, or in small clusters of four or five, of a very dark green colour. Articulations, except the basal one, which is short, about twice as long as broad, filled with a dark green mass, which at length separates into two portions. Dissepiments contracted, very narrow, pellucid. This species is widely dispersed throughout the Northern Atlantic, from the shores of Greenland to those of Britain, and extends along the shores of North America, as far as Boston, and perhaps farther southward. It is abundantly distinguished from all British species by the great diameter and rigidity of its nla- ments, which stand erect, if the water be removed from them ; but it seldom grows in places where it is left exposed on the recess of the tide. Its nearest affinity is with C. area, which I have therefore represented on the same plate ; but it is a much more rigid plant. A. Fig. 1. Conferva Melagonium ; some filaments: — of the natural size. 2. Portion of a filament : — magnified. Plate XCIX. B. CONFERVA ^REA, Mlw. Conferva area; root scutate, filaments elongated, setaceous, tufted, straight, harsh, brittle, yellow-green; articulations about as long as broad. Conferva area, Dillw. Conf. t. 80. E. Bot. t. 1929. Lyngb. Hyd. Ban. p. 147. t. 51. Ag. Syst. p. 100. Harv. in Hook. Br. Fl. vol. ii. p. 354. Ham. in Mack. Fl. Hib. part 3. p. 226. Harv. Man. p. 130. Wyatt, Alg. Bantu, no. 191. Mont. Canar. p. 184. /. Ag. Alg. Medit. p. 12. Kiitz. Phyc. Gen. p. 258. Conferva antennina. Bory, Bid. Class, t. 4. p. 392. Has. On sand-covered rocks, between tide marks. Frequent in many places. Geogr. Distr. Found on all the Atlantic coasts of Europe ; also in the Medi- terranean. Canary Islands. Descr. Filaments attached by a scutate base, three to twelve inches in length, as thick as bristles, harsh to the touch, but much less rigid than C. Melagonium, straight, densely tufted, of a beautiful yellow-green colour, which fades, in the Herbarium, to a greenish-white. Articulations about as loug as broad, or a little longer, their contents at length separating into two portions. Dissepiments sbghtly contracted. This is one of the many species of Conferva first brought to the notice of botanists in the excellent monograph of Dilhvyn, where a correct figure is given of it. It appears to be generally diffused throughout the Atlantic, extending even within the tropics. It is always a more tufted plant than C. Melagonium, paler in colour, of scarcely half the diameter, and, though harsh, far less rigid and quite unable to support itself when removed from the water. B. Fig. 1. Conferva ^rea j a tuft -.—of Ute natural she. 2. Portion of diffe- rent filaments : — magnified. Ser. BHODOsPBKJiBiE. Pam. Coccocarpea. Plate C. GRATELOUPIA FILICINA, 4- Gen.Chab. Frond fiat, more or less pinnate, membranaceous, flexible, solid, composed of densely interwoven, anastomosing, b ranching fila- ments ; those of the periphery moniliform, short and very strongly compacted together. Fructification; 1, globular masses of spores ( favelRdia) immersed beneath the peripheric stratum, and communi- cating with the surface by a pore ; 2, cruciate tetraspores vertically placed among the filaments of the periphery, in sub-defined sori. — Grateloupia {Ag.) t in honour of Dr. Grrateloup, a French Algologist. Gkatelouma filicina; frond linear, narrow, tapering to either extremity, irregularly once or twice pinnated ; pinnte flexuous, patent, contracted at the base and attenuated towards the apex. Grateloupia filicina, Jg. Sp. Jig. vol. i. p. 224. Syst. p. 241. Spray. Syst. Feg. vol. iv. p. 334. Grev. Jig. Brit. p. 151. 1. 16. Hook. Br. Fl. vol. n. p 306 Wyatt, Jig. Damn. no. 123. Harv. Mart. p. 83. J. Jg. Med it. p. 103. Endl. 3rd Suppl. p. 41. Kid:. Phyc. Gen. p. 397. Mont. Fl. Jlger. Grateloupia porracea, Kiitz. Phyc. Gen. p. 397. Delesseria filicina, Lamour. Ess. p. 38. Gelidium neglectum, Bory, Fl. Pelop. p. Fucus filicinus, Wulf. inJacq. Coll. vol.iii. p. 157. t. 15. f. 2. Turn. Hist. Fuc. 1. 150. Esper, Ic. Fuc. vol. i. p. 134. t. 67. Hab. On submarine rocks at half-tide level, frequently where small stream- lets run into the sea. Very rare. Perennial. Winter. Sidmouth and Efracombe, Miss Cutler. Barrowcane and Hagington, Mrs. Griffiths. Mount's Bay, Cornwall, plentiful, and at Aberystwith, Mr. Ralfs. Gboge. DlSTB. Atlantic shores of France and Spain. Abundant in the Medi- terranean. Cape of Good Hope. Indian Ocean. Descii. Fronds rising from a scutate base, tufted, seldom (in British specimens) more than two inches high, but, in warmer countries, reaching 8-10 inches in length, from half a line to a line in breadth, flexuous, flat, undivided or once or twice irregularly forked, sometimes nearly bare or with a few lateral branches, but more frequently closely pinnated with more or less regularity. Pinna opposite or alternate, "patent, distichous, flexuous, tapering to a fine point, narrowed at the base, simple, often pinnulated toward the apex, the pinnule sometimes irregularly forked. Tubercles (favellidia) crowded toward the base of the piuna;, in whose substance they are deeply imbedded,_ communicating with the surface by means of a pore, containing a mass of densely compacted spores. Tetraspores thickly scattered among the surface cells of accessory leaflets or pinnules, vertical, cruciately divided. Substance cartilagmeo-membranaceous, soft, but very tough. Colour a dull brownish red. _ 2b 2 The genus Gratelmpia contains several species, all of which are natives of the warmer parts of the temperate zone, about lat. 34° to 40°. G.Jilicina is the only one which has a very wide distribution, and it extends from the tropical ocean to the southern shores of Britain, where it becomes very mucb dwarfed in size, but where, nevertheless, it frequently produces fruit of both kinds. In the Mediterranean Sea, where it is common, the fronds are six or eight inches in expansion, and regularly and closely bipinnate, the pinnules an inch or more in length. Speci- mens from the Indian Ocean are very similar. Those from the Cape of Good Hope, while they are quite as long, have a much narrower outline, with shorter pinnae and pinnulae. The only British plant with which this is likely to be confounded, is Gelidium corneum, to some varieties of which, especially that which I have called jfe«os«w (PI. LIU. Fig. 2), it bears a very strong external resemblance. Its softer and more membranous substance will generally distinguish it to the feel ; and the microscope will point out a difference of structure, when closely examined. If in a state of fruit, there can be no difficulty in discriminating between them. The discoverer of G. filicina in Britain was Miss Cutler of Sidmouth, and the earliest notice of its occurrence appeared in Dr. Greville's ' Algae Britannicae'. It is still a desideratum in the flora of Ireland and of Scotland, but the chances of its being met with in the latter country are very feeble. Fig. 1. Grateloupia filicina : — the natural size. 2. A pinna with tetraspores in the accessory leaflets. 3. Vertical section of the same, showing the position of the tetraspores. 4. Tetraspores. 5. A pinna with tubercles. 6. Transverse section of the same : — all more or kss highly magnified. Ser. Melaxospermk.k. Fam. Ectocarpea. Plate CI. MYRIOTRICHIA CLAV^FORMIS, Harv. Gen. Chae. Filaments capillary, flaccid, jointed (simple), beset with quadri- farious, simple, spine-like ramuli, clothed with byssoid fibres. Fruc- tification, elliptical utricles (or spores?) containing a dark-coloured sporaceous mass. Myeiotrichia (Harv.), — from pip™, a thousand, and 6pi£, a hair. Myriotrichia clavqformis ; stem densely beset with quadrifarious ramuli, which gradually increase in length from the base upwards, giving the frond a club-shaped figure. Myrioteichia elavaeformis, Harv. hiHook.Journ.Bot. vol. i. p. 300. t. 138. Harv, in Mack. Fl. Hib. part 3. p. 182. TFyatl, Alg. Banrn. no. 131. Harv. Man. p. 44. Endl. 3rd Suppl. p. 24. Hab. Parasitical on Chorda lomentaria. Annual. Summer. Bantry Bay, Miss Hide/tins. Torquay, Mrs. Griffiths. Cable Island, near Youghal, Miss BaU. Korth of Ireland and Ballantrse, Ayrshire, Mr. W. Thomp- son. Howth and Balbriggan, Miss Gower. Mount's Bay, Cornwall, Mr. Ralfs. Falmouth, Miss Warren. Jersey, Miss While. Geogr. Distr. British Islands. Desce. Fronds tufted, half an inch or rather more in length, flaccid, subgela- tinous, simple, linear-clavate, dark olive brown, surrounded by colourless fibres. Primary thread articulated, bare of ramuli below for a short dis- tance above the'base, upwards densely beset with patent simple quadrifarious ramuli, the lowermost of which are very short or merely rudimentary, the uppermost gradually longer and those toward the apex frequently producing, in old specimens, a second series near their tips. From the apices and sides of the ramuli, and from the lower part of the stem, spring innumerable slender, byssoid, colourless, long-jointed fibres, which greatly increase the bulk of the plant, and impart to it the peculiar softness. Articulations of the stem and ramuli shorter than their breadth. Utricles elliptical, or somewhat ovate, sessile on the main threads, occupying the position of a ramulus, having a pellucid limbus and containing a dark-coloured sporaceous mass. Colour dark olivaceous brown. This curious little parasite, which, in some seasons, is not uncommon on the fronds of Chorda lomentaria, though far less common than the closely-allied M. fl if or mis, was discovered by Miss Hutchins about the year 1808, a circumstance unknown to me when, in 1S34, I published it as a novelty in the ' Journal of Botany. To the majority of botanists it was then indeed new, for no notice had been taken of Miss Hutchins's specimens in ' Eng. Bot.'; and no other observer had collected the plant until Mrs. Griffiths, in 1833, gathered the specimens which were described by me. In the account which I first published respecting it, I regarded it as more nearly allied to Ectocarpus than to any other genus, an opinion to which I still adhere, although Endlicher has placed it nearer to Cladostephus, to which its quadrifarious ramuli bear some resemblance. In the long hyaline fibres which plentifully cloth it in every state, it is distinct from both. These fibres I formerly described as being forked ; on a more careful examina- tion I cannot detect this character. They appear to issue indis- criminately from the apices, and the lateral sides of the ramuli. In the outline of the frond there is much resemblance to Dasy- cladus clavesformis, a curious Mediterranean Alga belonging to Siphonea ; but the structure is very widely different. Fig. 1. A frond of Chorda lomentaria infected with tufts of Mymotkichia clav.£formis : — the natural size. 2. A tuft of Myriotrichia clavajormis. 3. Two fronds, of different ages. 4. A section showing a utricle, subtended by a ramulus, and some of the hairs which clothe the latter : — all more or less magnified. Ser. Rhodospermeje. Fam. Iihodomelea. Plate CII. A. POLYSIPHONIA OBSCURA, J. a,,. Gen. Char. Frond filamentous, partially or generally articulate ; joints lon- gitudinally striate, composed of numerous radiating cells or tubes disposed round a central canty. Fructification two-fold, on different individuals ; 1, ovate capsules (ceramidia), furnished with a terminal pore, and containing a mass of pear-shaped spores. 2, tetraspores imbedded in swollen branchlets. Polysiphoni a [Grev.), from 7roXi>s, many, and aipav, a tube. Polysiphonia obscura ; densely matted together, filaments creeping, tin-ow- ing up erect, simple, secund branches, which are either naked or fur- nished with a few secund ramuli ; articulations as long as broad, many- tubed. Polysiphonia obscura, /. Ag. Alg. Medit. p. 123. Endl. 3rd Suppl. p. -i-f. Hutchinsia obscura, Ag. Sp. vol. ii. p. 108. Conferva intertexta, Roth, Cat. Bot. vol. i. p. 1S8. t. 3. f. 5. vol. ii. p. 814. Hab. Spreading over marine rocks, at half -tide level; also parasitical on Fuci, and on some of the smaller Alga;. Jersey, Miss White. On the sheltered side of a lofty rock, near Sidmouth/ifei;. Mr. Cresswell. Geogr.Distb. Coast of Spain, at Cadiz, Ag. Adriatic Sea. Descr. Plant spreading over the surface of rocks, in patches of six inches to a foot in diameter, covering the roots of such Fuci as it may encounter. Fila- ments decumbent, attached by means of rooting processes, which issue at intervals from the lower surface, subsimple, throwing up from the upper surface erect, secund branches, from a quarter to half an inch in length, quite simple, and tapering to a fine point, naked, or furnished with three or four secund simple ramuli. Articulations visible in all parts of the frond, about as long as broad, or rather shorter, composed of twelve or thirteen radiating tubes. The fruit I have not seen on British specimens. Colour, dark brown-red. Suistatice rigid, imperfectly adhering to paper. This interesting addition to the British Flora, was made by Miss White, who detected, in 1S46, a single specimen growing among the roots of P. fbrata, at Jersey. More recently it has been gathered in great abundance by the Rev. Mr. Cresswell, in a station near Sidmouth, and to his kindness I am indebted for numerous specimens, gathered at various seasons. I had, at first, confounded it with P. secitnda, Mont., a plant to which, outwardly, it bears a strong resemblance, but from which it differs in the length, and composition of the articulations. I have now minutely compared the British specimens with one of P. obscura, received from Prof. J. Agardh, and find them to agree in all essential particulars ; ours are, however, rather more robust than the Adriatic plant, and the joints slightly shorter. A. Fig. 1. PolysiphoNIA obscuka j part of a patch : — of the natural size. 2. Portion of a creeping filament -.—moderately magnified. 3. Portion of a branch. 4. Cross section of the same : — both highly magnified. Plate CII. B. POLYSIPHONIA PULVINATA, Spreng. Polysiphonia pulvinata ; filaments rising from a mass of creeping fibres, tufted and interwoven, short, very slender, flexuous, sparingly and irregularly dichotomous, more or less furnished with very patent or re- curved, simple ramuli ; articulations of the main branches three or four times as long as broad, of the ramuli very short, four-tubed ; capsules urn-shaped, stalked. Polysiphonia pulvinata, Spreng. Syst. Veg. vol. iv. p. 350. /. Ag. Alg. Medit. p. 124. Mont. Fl. Conor, p. 172. Endl. 3rd Suppl. p. 44. Earv. Man. p. 94. Wyatt, Alg. Damn. no. 215. Polysiphonia macrocarpa, Earn, in Mack. Fl. Eib. part 3. p. 296. Hutchinsia pulvinata, Ag. Sp. Alg. vol. ii. p. 109. Confeeva pulvinata, Roth. Cat. vol. i. p. 187. t. 3. f. 4. vol. ii. p. 214. Hab. On rocks in the sea, between tide marks. Annual. Not uncommon. Miltown Malbay, W. H. H. Port Stewart, Mr. D. Moore. Ilira- combe and Torbav, Mrs. Griffith. Salcombe, Lands-End and Mount's Bay, Mr. Ralfs. "Balbriggan, Miss Gower. Saltcoats, Mr. B. Lands- borough, Jun. Ardrossan, Major Martin. Geogr. Distr. Atlantic and Mediterranean coasts of Europe. Canary Islands. Descr. Filaments rising from creeping fibres, densely aggregated in roundish, fastigiate tufts, about an inch in height, very slender and flaccid, flexu- ous, irregularly branched ; branches more or less dichotomous, furnished irregularly with scattered, alternate or now and then secund, very patent. or "divaricating, short ramuli, which are mostly simple, occasionally subdivided. Articulations variable in length; those of the main divi- sions three to four times, of the lesser branches twice or thrice, and of the ramuli half as long as broad, all marked with two broad, coloured bands, and composed of four tubes radiating round a central canty. Cap- sules large in proportion to the diameter of the filaments from which tin \ spring, urn-shaped, with a contracted orifice, borne on short lateral stalks. Tetraspores imbedded in the rainuli in a single row. Colour a dark red- brown. Substance soft and somewhat gelatinous, closely adhering to paper. This resembles P. vrceolata in miniature, but has the soft substance of P.fibrata, and is a much more slender plant. B. Kg. 1. PoLYSirnoNiA pulvinata; a tuft : — of the natural si:e. 2. Por- tion of a filament -.—moderately magnified. 3. A ramulus with tetraspores. 4. Portion of a branch, with capsule". 5. Transverse section of a branch : all highly magnified. Ser. Mblasospbeme.*. Fam. Dktyoteo: Plate CIII. DICTYOTA DICHOTOMA, Lemour. Gen. Chak. Boot coated with woolly fibres. Frond flat, membranaceous, ribless, reticulate, dichotomous or irregularly cleft. Fructiji 'cation, scattered clusters of spores formed beneath the cuticle, through which they finally burst ; or, on distinct plants, solitary spores irregularly dispersed over the surface. Dictyota {Lama-.)— from St*™,*, a net; because the surface is reticulated. Dicttota dicltotoma ; frond regularly dichotomous, linear; segments cu- neate at the base, erect or erecto-patent, gradually narrower towards the apices, axils rounded. Dictyota dichotoma, Lamour. Ess. p. 58. Grev. Alg. Brit. p. 57. 1. 10. Hook. Br. Fl. vol. ii. p. 280. Earn, in Mack. Fl. Eib. part 3. p. 177. JTyatt. Alg. Banm. No. 10. Han. Man. p. 32. Buby. Bot. Gall. p. 954. Menegh. Alg. Hal. and Balm. p. 224. Endl. 3rd. Suppl. p. 24. Mont. Fl. Alg. p. 30. Zonaria dichotoma, Ag. Sp. Alg. vol. i. p. 133. Ag. Syst. p. 266. Hook. Fl. Scot. vol. ii. p. 90. Grev. Fl. Edin. p. 297. Dichophyllium vulgare, Kutz. Bhyc. Gen. p. 337. t. 22. II. f. 1-4. Dichophtllium dichotomum, Kiitz. I. c. p. 338. Haliseris dichotoma, Spreng. Syst. Veg. vol. 4. p. 328. Ulva dichotoma, Hitds. Fl. Aug. Ed. vol. ii. p. 568. (ed. vol. i. p. 476.), Light/. Fl. Scot. p. 975. t. 34. With. vol. iv. p. 124. Eng. Bot. t. 774* Lyngb. Hyd. Ban. p. 31. t. 6. C. Var. £. intricate: ; frond very narrow, much branched, twisted and entan- gled, Grev. Dictyota dichotoma, /9. intricata, Grev. Alg. Brit. p. 58. Menegh. Alg. Hal. and Balm. p. 227. Dictyota implexa, Lama: I. c. J. Ag. Alg. Medit. p. 37. Mont. Fl. Alg. p. 30. Dichophyllium iinplexum, KiH:. Phyc. Gen. p. 338. Hab. Parasitical on various Algae ; also growing on rocks and stones in tide-pools near low-water mark, and at a greater depth. Annual. Summer. Both varieties common on the British Coasts. Geogr. Distr. Abundant throughout the Atlantic Ocean, extending from the shores of Norway to the tropic. Southern Ocean, Western Shores of South America ; Cape of good Hope ; New Zealand. Descr. Root small, coated with fibres. Fronds several from the same base, from three to twelve inches in length, from \ to i an inch in breadth, cuneate at base, afterwards nearly linear, very many times divided in a regularly dichotomous manner ; segments generally very erect, with narrow interstices, occasionally more or less spreading. Substance delicately membranaceous, Colour olivaceous towards the tips. Fructification ; oval clusters of spores 2 c covered at an early age with a vesicular membrane formed by a blistering of the cuticle, fixed^ by their bases, obovate, with a wide limbus, and finally parted into four sporules. 2. (on distinct plants) solitary, roundish spores (?) scattered among the cells of the surface.— Var. /3. is very much narrower, about a line in diameter at the base, and not a fourth of a line above, dark brown, coarser in substance, with more patent axils, and frequently spirally twisted. A very common plant, the most widely dispersed of the gemis to which it belongs, being found along the shores of the greater part of the temperate ocean, and also in many intertropical localities. As might be expected, it varies considerably according to the circumstances under which it grows, though without any respect to climate, the most opposite varieties being frequently found on the same shore. The variations appear to result merely from the depth of water at which the plant grows, and the degree of exposure to waves and currents to which it is subjected. In rock-pools near high-water mark and to half-tide level the narrow variety, which sometimes is much narrower and greatly more intricate than our figure represents, is the commoner. Near low- water mark in rock-pools, and among the Laminaria in sheltered bays, the broad variety occurs, of which the average size is represented in the figure ; but some specimens in my Herbarium, gathered by Miss Hincks, at Ballycastle, on the coast of Antrim, are very much wider and proportionably less compound, and bear a considerable resemblance to the tropical D. Sc/iroderi. The narrow variety, especially when spirally twisted as it commonly is, looks very like a different species, and is regarded by several continental authors as such. But it is merely distinct in its extreme forms. Intermediate specimens connect it abso- lutely with the broader individuals, and differences in relative breadth are the most uncertain of all characters, especially among the leafy marine plants. The diameter of cylindrical kinds is more constant. Fig. 1. Dictyota dichotoma, var. a. 2. The same, var. fi: — both of the natu- ral she. 3. Portion of the frond with a vertical view of a sorus. 4. A ver- tical section of a sorus. 5. A spore. 6. Portion of the frond, with scattered spores : — all magnified. J K-VJV ' x Ser. Rhodosperme.e. Fain. Coccocarpea. Plate CIV. GIGARTINA ACICULARIS, Lamm. Gen. Char. Frond cartilaginous, either filiform, compressed or flat, irregu- larly divided ; purplish-red ; the axis or central substance composed of branching and anastomosing longitudinal filaments ; the periphery of dichotomous filaments laxly set in pellucid jelly; their apices moniliform, strongly united together. Fructification double, on dis- tinct plants ; 1 . external tubercles containing, on a central placenta, dense clusters of spores (favellidia) held together by a net- work of fibres ; 2, tetraspores scattered among the filaments of the periphery. — Gigartina (Lamour.), from yiyaprov, a grape-stone ; winch the tuber- cles resemble. Gigartina acicularis; frond cylindrical, filiform, irregularly branched, between pinnated and dichotomous; branches divaricating, curved; ramuli few, very patent or recurved, subulate, often secund ; tubercles spherical, scattered on the branches. Gigartina acicularis, Lamx. Ess. p. 49. Gaill. Diet. Sc. Nat. 53. p. 365. Duby. Bot. Gall. p. 953. Grev. Jiff. Brit. p. 147. 1. 16. Hook. Br. Ft. vol. 2. p. 300. Wyait, Jig. Damn. No. 26. Han. Man. p. 75. /. Jg. Jig. Medit. p. 105. Mont. Fl. Jlger. p. 100. Kictz. Phgc. Gen. p. 403. Sph.erococcus acicularis, Jg. Sp. Jig. 1. p. 322. Jg. Syst. p. 237. Fccus acicularis. Wulf. Crypt. Jquat. No. 50. Turn. Hist. t. 120. Sin. Eng Bot. t. 2190. Hab. On submarine rocks, near low-water mark. Annual. Winter. Rare. Cornwall, Mr. W. Rasldeigh. Ilfracombe, Lupton Cove and Torquay. Mrs. Griffiths. Sidmouth, Miss Cutler. Jersey, Miss White and Miss Turner. Belfast Bay, Mr. Templeton. Valentia, abundant ; Kilkee, very rare, W. H. H. Geogr. Distr. Abundant on the shores of France and Spain. Mediterranean Sea. Indian ocean, JFighl. Tasmania, Dr. Hooker. Descr. Root discoid, accompanied by decumbent, branching fibres. Fronds two to four inches high, as thick as small twine, densely tufted, and often matted together, very irregularly branched ; sometimes the main divisions of the frond are tolerably regularly chchotomous, four or five times divided, with very patent axils, and long naked segments, forked at the tips, and bare of ramuli ; sometimes and more frequently, they are more or less regularly pin- nate, the main stem angularly flexuous, furnished with several, opposite or alternate, divaricating, or frequently recurved, elongated sub-simple, and nearly distichous branches, which are naked below, and more or less fur- nished in their upper part with very patent ramidi Ramuli various in length, sometimes short and spine-like, sometimes elongate and furnished with a second series, all tapering to an acute point. Substance firmly car- tilaginous, when first gathered long resisting the action of fresh water; 2 c -: but if once dried, and again moistened, it soon decomposes. Tubercles very rare, as large as poppy-seed, irregularly scattered over the branches and ramuli. Tetraspores I have not seen. Colour a dull purple red, becoming pink in fresh water. The genus Gigartina has been peculiarly unfortunate in the revolutions which it has undergone according to the views of different authors, or of the same authors at different times. As originally established by Lamouroivx, its limits were very uncer- tain indeed, and it included a heterogeneous assemblage of species among which Laurencia dasyphylla, Rhodomela mbfmca, C/wr- daria flagettiformis, and the Chylocladice, with several others were associated together. Lyngbye, while he weeded out several false species added to the confusion by introducing Desmarestia viridis. The first real reformation of the genus was that proposed by Dr. Greville in 1830, though he has admitted some species of an opposite structure to that of his type, and excluded others which coincide with it. I was myself accessory to a step being made in the wrong direction in Sir W. J. Hooker's ' British Flora', where the Gracilaria are erroneously combined with the Gigartina. That the combination is unnatural wUl be evident by a comparison of the magnified sections of our present plate, with those given of Gr. confervoides at PI. LXV. ; the structures are widely different. The last revision of the genus, by Professor J. Agardh, has at length fixed structural limits, more natural than those ascertained by mere outward habit, and from this results the rather startling fact, that Iridcea radula, Bory, is a true species of Gigartina. Separated from its affinities such a connexion would hardly be supposed, but the passage through Iridcea stiriata, to Gigartina livida, and from that to the subject of our present plate is easy and natural. Besides G. acicularis, we have two other British species, G. pistillata and Teedii, both plants of extreme rarity in this country, though abundant in the South of Europe. G. plicata and G. Griffithsiee, of ' British Flora' have been formed into a separate genus ; and the remaining species restored to Gracilaria. Fig. 1. Gigartina acicularis, a barren specimen. 2. A specimen in fruit ; both of the natural size. 3. A nunulus with tubercles. 4. A section of a tubercle. 5. Spores. 6. Tart of a transverse section of the frond. 7. Fart of a longitudinal section : — all magnified, the lino latter figures highly to. Sear. ChlorospermejE. Fain. Oscillaloriea. Plate CV. A. OSCILLATORIA LITTORALTS, Carm. Gen. Char. Filaments lying in a mucous matrix, rigid, simple, acicular, vividly oscillating. Tube continuous ; endocrome green, densely annu- lated with close, parallel, transverse striae. — Oscillatoria, (Fauci.), from the motion observed hi the filaments, which resembles the oscil- lations of a pendulum. Oscillatoria littoralis, Carm. Stratum of a vividly seruginous green colour ; filaments thick, dark green, variously curved ; striae conspi- cuous, close-set. Oscillatoria littoralis, Carm. Jig. Appin. wed. Han. in Hook. Brit. Ft. vol. ii. p. 375. Hare. Man. p. 165. Hab. In pools, along the muddy sea shore, flooded by Spring tides. Appin, Capt. Carmiciael. Desce. Stratum exceedingly thin, slimy, bullated by the extrication of air bubbles, of a dark green colour, spreading to an indefinite extent over the muddy bottom of the pool. Filaments 1-2 fines long, much thicker than those of 0. nigra, straight or slightly curved, radiating very irregularly, and gene- rally in twisted bundles. StrUe strongly marked, at intervals of about one third the diameter of the filament ". Carm. I. c. Of this I have only seen Capt. Carniichael's specimens, from one of which the figure is taken. I find the filaments curved and twining together; the striae very dense, and the mass of endochrome divided at uncertain intervals into portions, which probably break off eventually and become new filaments. ./. Fig. 1. Oscillatoria littoralis, part of a stratum-.— of the natural size. 2. Filaments : — highly magnified. Plate CV. B. OSCILLATORIA SPIRALIS, Carm. Oscillatoria spiralis; stratum membranaceous, or coriaceous, feruginous or blackish-green ; without much lubricity ; filaments slender, spirally twisted, densely interwoven, radiating in all directions. Oscillatoria spiralis, Carm. Jig. Appin. ined. Han. in Hook. Br. Fl vol 2 p. 377. Hare. Man. p. 167. Oscillatoria subsalsa, Hare. I.e. p. 376. Hare. Man. p. 165. Spirillum rupestrc, Hass Freshw. Jig. p. 277. t. 75. f. 6. IIab. On rocks by the sea-side, above and between tide marks. At Appin by rocks where birds are in the habit of resting, Capt. Carmiciael. Brighton, on a plank between high and low water mark, Mr. Borrer ; Rocks by the Sea, Penzance, Mr. Ralfs. Georg. Distr. Coast of France. Descr. Stratum of indefinite extent, firm, membranaceous or coriaceous, peeling off in large flakes, without much lubricity, and without gloss when dry, of a dark green when growing above high-water mark, and a blueish green when submerged. Filaments slender, densely interwoven together, twisted like the letter S, or like a corkscrew, radiating in all directions. The specimens from the South of England are of a much brighter colour, and the stratum thinner than in the original Scotch specimens, but the microscopic character is very similar. Whether the 0. subsalsa of Agardh be different, 1 am unable to say. B. Fig. I. Oscillatoria spiralis; part of a stratum: — of the natural rise. 2. Filaments : — highly magnified. Plate CV. C. SPIRULINA TENUISSIMA, Kutz. Gen. Char. Filaments lying in a mucous layer, rigid, simple, spirally twisted, vividly oscillating. Tube continuous; endochrome green, more or less distinctly annulated. — Spirulina (Turp.). a diminutive of spira, a twist or curl. Spiruldja tenuissima ; "stratum very lubricous, seruginous, subradiant; filaments densely spiral, very blender, parallel, flexuous ". Spirulina tenuissima, Kutz. Phyc. Gen. p. 183. Ralfs, in Ann. Nat. Hist. vol. xvi. p. 309. PI. 10. Hab. On decaying Alga in a brackish pool near the Menai Bridge, and on sticks in brackish pools at Penman Pool near Dolgelly, Mr. Ralfs. Aberdeen, Dr. Dickie. Geogr. Distr. Europe. Descr. " It forms at first a thin pellicle of a rich green colour, but in an ad- vanced state becomes somewhat skin-like and tinged with brown; the filaments are extremely slender, of a pale blueish green colour, elongated, straight when free, equal, not attenuated at the extremities, vividly oscillating. Spires very close, like the volutions of some shells, broader than long. There is no appearance of granular matter, aud the filaments are so fine that I cannot ascertain whether they are jointed ". Ralfs. I. c. Having never seen this plant in a living state, I prefer giving Mr. Ralfs' excellent description in his own words. I am indebted to Dr. Dickie for beautiful dried specimens, from one of which my figure has been taken. C Kg. I SeiuruNA tenvissima. iiari of t hr -t rat uiu .— »/' He natural m, 2. Filaments,; — Monty 'nagniji<idl. 3rd Suppl. p. 37. Mesogloia divaricata, Ag. Sgst. Alg. p. 51.' Kith. P/igc. Gen. p. 332. Mesogloia Hudsoni, Hare, in Hook. Br. Fl. vol. ii. p. 3S6 (not of Ag.). Hon. in Mack. Fl. Hib. part 3. p. 1S6. TFyatt, Alg. Damn. no. 99. Harv. Man. p. 47. Ulva rubens, Huds. Fl. Ang. p. 571. Hab. On stones, and the smaller Algae, near low-water mark, and at a greater depth. Annual. Summer and autumn. Generally distri- buted round the British shores ; more abundantly in the north. Los- siemouth, Mr. Brodie. Appin, Copt. Canmehael. Arran and Salt- Coats, Tier. It. Xiandsborowrh. Orkney, Bev. J. H. Pidlexfen, Lieirf. Thomas, and Dr. Me' Bain. Sidmouth and Torbay, Mrs. Griffiths. Falmouth, Miss Warren. Jersey, Misx WMte. Abcrfaw, Mr. Raffs. Killiney and Kilkee, W. II. II. Howth, Miss Gower. North of Ireland, Mr. Thompson. Roundstone Bay, Mr. Me' Gil In. Geogr.Distr. Northern Atlantic, as far south as the French shores of the British Channel. Baltic Sea. Descr. Root minute. Fronds densely tufted, 6-8 inches long, or more, about half a line in diameter, preserving an equal thickness throughout, with a simple or forked main stem, densely clothed with lateral branches. Lowest branches longest, the rest gradually shorter towards the apex, so that the outline is pretty regularly ovate, all very patent, horizontal or divaricate, in some specimens pretty regularly alternate, in others generally opposite, flexuous, pinnate or bi-pinnate, with divaricating lesser branchlets. Ramuli numerous, filiform, squarrose. Substance firmly gelatinous and elastic. Colour a pale red, or red-brown, becoming darker in the herbarium. Favdhe very commonly produced, imbedded in the whorled filaments of the periphery, to which they are attached. Tetraspores I have never seen. This species is well known to British botanists as the Meso- gMa Htidsoni, of the ' British Flora ', and is, I have little donbt, the plant intended by Hudson, under the name JJlva rubens ; his description " U. gelatinosa filiformis ramosissima rubescens, ramis sparsis horizontalibus obtusis ", being strictly applicable. But it is not the plant called MesogMa Hudson i by Agardh, which it seems, is merely a variety of Hatymenia ligulata ; and it unques- tionably is the species long known on the Continent under the name MesogMa divaricata, and recently admitted into the genus Dudresnaia; a genus typified by Mesogloia coccinea and its allies. Though I consider it probable that Hudson was the ori- ginal observer, still, as a doubt rests on his synonyme, I here adopt the modern name, given by Agardh, because it is that in common use, except in Britain. It is still a question whether this plant really belongs to the genus Dudresnaia, and not rather to Newueleon. If we judge it by outward habit it will be placed in the former ; but there is certainly an approximation in structure to the latter, although the axis is less dense and somewhat differently constructed. The fructification is imperfectly known. I have sought in vain among a large number of specimens, from different localities, for tetraspores. Mrs. Griffiths has been equally unsuccessful. Nor has M. Chauvin, on the coast of Normandy, been more fortunate. All the specimens we have independently examined, produce favellidia, which appear' to be formed in abundance on every full-grown plant. As this is also the case with Nem&leon multi- fidum, it may be questioned whether it woidd not be more cor- rect to place D. divaricata in the same genus. Dudresnaia divaricata abounds throughout the Northern Atlantic, gradually diminishing to the south of the British Islands. It has not been found in the Mediterranean. Fig. 1. Dhdesnaia divaricata :—of /lie natural size. 2, Transverse section of a segment of the frond. 3. .Longitudinal section of the same: — both highly magnified. Set. Mui.A\<>spi<:i{,\rivi;. Fam. Chordariea. Plate CXI. CHORDARIA FLAGELLIFORMIS, Ag. Gen. Char. Frond filiform, mucli branched, cartilaginous, solid. Axis composed of densely packed, longitudinal, interlaced, cylindrical fila- ments ; the periphery, of simple, club-shaped, horizontal, whorled filaments, and long, byssoid, gelatinous fibres. Fructification, obovate spores, seated among the filaments of the periphery. Chordaria {Ag.), — from chorda, a cord. Chordaria flagelliformis; frond subsimple, furnished with closely-set, long, simple, filiform branches, ramuli very few or none ; filaments of the periphery club-shaped, the terminal cellule large or small. CHORDAEIA flagelliforrnis, Ag. Syn. p. 12. Lyngh. Hyd. Ban. p. 51. t. 13. Ag. Sp. Alg. vol. i. p. 166. Ag. Syst. p. 256. Hook. Fl. Scot, part 2. p. 98. Grev. Fl. Edin. p. 288. Grev. Alg. Brit. p. 44. t. 7. Hook. Fl. Brit. vol. ii. p. 275. Hare, in Mack. Ft. Ilib. part 3. p. 183. Harv. Man. p. 45. JFyatt, Alg. Banm. no. 57. Kiltz. Pliyc. Gen. p. 332. t. 27. f. 3. Ertdl. 3rd Sitppl. p. 23. Gigartina flagelliformis, Lamonr. Ess. p. 48. Fucus flagelliformis, Fl. Dan. t. 650. Turn. Syn. vol. ii. p. 335. Turn. Hist. t. 85. Sm. E.Bot. 1. 1222. Hab. On rocks and stones in the sea, between tide-marks. Annual. Summer. Common on the shores of the British Islands. Geogr. Distr. Abundant on the Atlantic shores of Europe, from Iceland to France. Eastern coast of North America. Cape of Good Hope. Descr. Root a minute disc. Fronds tufted, from six inches to two or three feet in length, preserving throughout an uniform thickness, of about half a line, furnished with a simple or sparingly forked stem, which is densely clothed from its base to its summit with lateral branches, which issue at distances varying from a tenth to half an inch. Branches from six to twenty inches long, cord-like, perfectly simple, and generally naked ; but now and then furnished with a few, filiform, often secund ramuli, widely distant from each other. In the young plant, the branches are very short, the stem often developing to its fidl extent, while the branches are rudimentary, in which state it may readily pass for a different species. Spores abundantly pro- duced in the full-grown plant, formed at the base of the peripheric fila- ments. The structure of the axis is very dense and firm, composed of closely combined interlacing filaments. The filaments of the periphery vary in form as the plant advances in age; when young, they are club-shaped, but in age more or less capitate. Colour verj dark brown. Substance cartilaginous, with a slimy coat. It closely adheres to paper, which it stains of a rusty colour. A very common plant in the North Atlantic, but strangely misunderstood by early writers, who confounded it with Gracila- ria confervoides ; a mistake which, with modern microscopes, it would be impossible to fall into. It was first clearly defined as a species, in the 'Flora Danica,' and was afterwards made the type of a distinct genus, which in modern systems, represents a separate family, widely parted from that to which G. confervoides belongs. The only resemblance between these plants is, that both have long, and often simple branches. Neither in structure, in substance, or in colour, is there any identity. The fructification, which was first described by Turner, has been overlooked by many authors, and yet it is not unfrequently produced. I have generally found an abundance of spores in full-grown plants, gathered in the months of July and August. They may most easily be elicited by compressing a small part of a branch between two pieces of glass, and appear to exist in equal numbers in all parts of the plant. At Plate XVII. we have represented the only other British species of Chordoma yet discovered. By comparing the figure now given, with that plate, the differences and resemblances will be readily appreciated. In younger plants of C. pigelliformis the filaments of the periphery are exactly club-shaped ; in more fully grown individuals, the terminal cellule is larger, and more resembles that of C. divaricata than I formerly supposed. But the difference in ramification is so great that there can be no difficulty in discriminating between these species. Fig. 1. ClIORDARIA FLAGELLIFORMIS : — of the natural »&. -'. Part of a cross section of the frond. 3. Longitudinal section of the same. -t. Filaments of the periphery and spore. 5. A spore removed. ( Iw V -> Ser. Rhodospeume.*. lam. Gaskrocarpe/t. Plate CXII. HALYMENIA LIGULATA, Ag. Gen. Char. Frond compressed or Hal, pinky red, gelatmoso-membranaceous, consisting of a delicate membrane, whose walls are separated by a very lax net-work of jointed fibres ; cells of the membrane minute, coloured. Fructification, spherical masses of spores (jfavellidia) immersed in the frond, attached to the inner surface of the membranous periphery. IIalymexia [Ag.), — from dAs, the sea, and hfapi, a membrane. Halymenia lignlata ; frond compressed or flat, irregularly dichotomous or palmate, the segments attenuated, often proliferous at the margin. Halymema lignlata, Ag. 8$. dig. vol. i. p. 210. Ag. Sgst. p. 244. Spreng. Sgst. Veg. vol. iv. p. 333. Oreo. Alg. Brit. p. 162. 1. 17. Hook. Br. Ft. vol. ii. p. 308. flora in Mack. M. llih. part 3. p. 188. Hare. Man. p. 52. Wgatt. Alg. Danm. no. 425. Endl. Zr& Suppl. p. 40. Haiamenia elongata, Ag. Sp. Jig. vol. i. p. 209. Ag. Sgst. p. 243. /. Ag. Medit. p. 98. Halarachmon ligulatum, Kite. Phjc. Gen. p. 394. t. 74. f. 1. Ulva ligulata, Woodw. in Linn. Trans, vol. iii. p. 54. E.Bot. t. 420. Ulva rubra, Hiuh. Fl. Ang. p. 571. E. Bot. 1. 1627. Mesogloia Hudsoni, Ay. Sgst. p. 50 (not of British authors). Hab. On rocks and stones near low-water mark, rare ; more usually dredged in 6-10 fathoms water. Annual. Summer. Frequent on the southern shores of England, in many places. Coast of Norfolk, Mr. L. W : iqg, Mr. Turner, &c. Anglesea, Rev. H. Buries. Mast, south and western shores of Ireland. Very common in Jersey, Miss White and Miss Turner. Rare in Scotland ; Orkney, Rev. J. H. Pollerfen. Geogr. Distr. Atlantic shores of Europe. Mediterranean Sea. Descr. Boot small, scutate. Frond extremely variable in ramification, and even in substance, but resolvable into three principal varieties, a.dichotoma ; frond six to eight inches long.from half a line to one or two lines broad, compressed, very •relafinous, many times divided in an irregularly dichotomous manner, the divisions nearly of equal breadth, becoming gradually narrower toward the extremities, which are acuminate. ji. ramentacea ; frond twelve to fourteen inches long, or more, half an inch in breadth, compressed, gelatinous, di- vided into three or four principal branches, from the sides of which issue very numerous, simple or occasionally forked ramenta constricted at base, tapering to an acute point, cylindrical or nearly so. Occasionally the ramenta are very thin, almost setaceous, and proportionality numerous and subdivided, y.' tatifolia; frond twelve to twenty inches long, two to four inches wide, perfectly Hat, stipitate, wedge-shaped, simple or forked, or irregularly palmate, of a darker colour, and less gelatinous substance than the two former varieties. Colour varying from a pale to a strong rose-red, or in the broad variety a deep red. Substance gelatinous and tender, very o ... o ii \\ .- soft, elastic, and adhering to paper, shrinking very much in drying. Fruc- tification, abundantly scattered through the whole substance of the frond, resembling minute dots. Though probably first noticed by Hudson, whose Ulva rubra we have quoted as a synonyme, this plant was first clearly des- cribed, and its characters defined by Woodward, in the ' Linn. Trans.' for the year 1797. Among British Algae few exhibit wilder variations in form, and yet I have never known it to be mistaken by any person who has once had the advantage of seeing it in a living state. The pinky colour, and peculiarly soft sub- stance, between gelatinous and membranaceous, and the innume- rable dots of fructification are found in every specimen, and sufficiently mark the species. In form and size, there is extra- ordinary variety. The specimens we have selected for illustration, unlike as they are, are only very moderately different, compared to some others which exist in our herbarium. And yet an ex- tensive suite of forms exhibits so perfect a gradation from the narrowest and most compound, to the broadest and most simple, that it is impossible to fix exactly the limits where one variety ends, and another begins. That all. therefore, belong to one species, is generally allowed. Possibly the H. elongata of Agardh, of which I have seen no authentic specimen, may be, as Prof. J. Agardh states, a distinct plant. But the specimens winch I possess under this name, are certainly only a narrow form of H. litptlata, such as is frequently found on the south coast of England. Our variety y, latifolia, in its typical form, has much more the characters of a species, distinguished by a thinner and more compact substance, and a darker colour. Pig. 1. Haiamkma i.Uiii.ATA, var.JS. and y.. small specimens: — of the natural me. '2. A. transverse section of the frond. 3. Portion of the membranous wall. I. A i'au'llidinm. .">. Spores. Ser. Chlorosper.me.e. Fam. Nbstoe&inea. Plate CXIII. A. SPHiEROZY GA CARMICH AELII, Haw. Gen. Char. " Filaments free, simple, rnomliform, consisting of a scries of ordinary cells interrupted here and there by a cell of a different kind [connecting-cell ), which is generally of a larger size, and often ciliated." Tlur. Spores formed from the ordinary cells. Sph^erozyga [Ag.), — aipa, a sphere, and £iyos, a yoke. The name Anabaina, applied to this genus by Bory, is pre-occupied for a genus of Euphorbiacem, by A. de Jussieu. Sph.erozyga Carmichaeli.i ; "spores large, oblong, twice or thrice as long as broad, commencing to be formed from the cells nearest the con- necting one." 27/10. in I'M. Belonia torulosa, Can//. Alg. Appin. iued. Hare, in Hook. Br. Fl. vol. ii. p. 379. Hare. Man. p. 1(57. Anabaina marina, Breb. in An. Sc. Nat. Hab. On decaying heaps of marine Alga;, also in ditches of brackish water. Appin, Copt. Carmichael. Near the Menai bridge; also at Barmouth, and Penman Pool, near Dolgelley, Mr. Half's. Shorehampton, near Bristol, Mr. G. H. K. T/nva'des. Geogr. Distr. Probably throughout Europe. Descr. " In the beginning of autumn, vast quantities of filamentous Alga; are detached from their places of growth, and deposited here and there along the shore in extensive fleeces. When these fleeces begin to decay, this plant makes its appearance in the form of a very thin gelatinous pellicle, of a vivid green colour, spreading over the surface of the decaying mass. The pellicle is made up of straight" (or slightly curved), "brittle, monili- form filaments, one fourth of a line in length, and tapering at both ends." Carm. Spores of considerable size, remaining green, or assuming a brownish colour, when mature. I have compared specimens of Anabaina marina, Breb., re- ceived from Messrs. Ralfs and Thwaites, with Carmichael's origi- nal Belonia torulosa; and find them to agree in every essential particular. This plant is unquestionably a Sphterozyga, to all the individuals of which genus the specific name " torulosa," which has the priority, is equally applicable. I have therefore dedicated this curious and beautiful parasite to the memory of its first discoverer, whose patient investigation of Cryptogainic plants has added so much to our knowledge of the more minute kinds. A. Fig. 1. Sph.erozyga Carmichaelii ; appearance of the mass. 2. Filaments: — magnified. Plate CXIII. B. SPH/EROZYGA THWA1TESII, Narv.(n.8p.) Sph.ekozyga TAwaitesii; " spore# elliptical, once and a half as long as broad, commencing to be formed from the cells most distant from the ciliated [connecting) one." TAio. in lilt. Anabaina Thwaitesii, Hurt. MS. Hab. On the muddy sides of ditches of brackish water, also floating. Bolgelly, Mr. Rolfs. Shorehampton, near Bristol, Mr. G. H. K. Thwaites. Porbury, Somerset, Mr. Broome. Geogr. Distr. Probably in similar situations throughout Em-ope. Descr. " Very gelatinous, deep green, sometimes almost black. Filaments pale oreen, curved, entangled ; connecting cells large, ciliated, subspherical, slightly oblong, of a lighter colour than the ordinary cells, which are some- what compressed. Spores of a deep brown, when mature." Thr. in lilt. My first acquaintance with this little plant was from a beau- tifully mounted specimen, communicated by G. H. K. Thwaites, Esq., of Bristol, to whom I am indebted for valuable notes and sketches of the three species now figured, without which assis- tance I should scarcely have ventured to publish them. I wish it therefore to bear the name of this gentleman, though I have since learned that it was originally detected by Mr. Ralfs, who has also, with his usual kindness, favoured me with notes and remarks. Mr. Thwaites observes that the connecting cell, which in this species is ciliated, is generally placed at or near the end of the filament, a peculiarity also noticed in Anabaina vekftina, Breb., and in some others of this genus. B. Fig. 1. Sph.£rozyga Thwaitesii ; appearance of the mass. 2. Filaments: magnified. Plate CX1II. C. SPERMOSIRA LITOREA, mtz. Gen. Char. "Filaments slightly mucous, free, simple, cylindrical, enclosed in a very delicate, membranous tube. Cells lenticular ; connecting cells larger, compressed." Thiv. Spores formed from the ordinary cells. Sperjiosira {Kiit;.), — from tnrippa, a seed, and golden, and 'vy-riv, a membrane ; because the species acquire golden tints if long steeped in fresh water. Chrysymenia clavellosa ; frond gelatino-membranaceous, very much branched in a repeatedly pinnate manner, branches of various lengths, mostly distichous ; ramuh distichous or quadrifarious, attenuated at base; capsules conical. Cheysymenia clavellosa, ./. Ag. Medit. p. 107. Endl. Zrd Suppl. p. 42. Chondrothamxion clavellosum, Kits. Phyc. Gen. p. 438. t. 53. f. 2. Chondrothammon coufertum, Be Not. Chylocladia clavellosa, Hook. Br. Ft. vol. ii. p. 297. Wyatt, Alg. Banm. no. 23. Earv. in Mack. Ft. Hib. part 3. p. 199. Han. Man. p. 71. Gastriditjm clavellosum, Li/ngb. Hyd. Ban. p. 70. t. 17. Grev. Alg. Brit. p. 115. Gastridium purpurascens, Lyngh. I. c. p. 69. t. 17. Chondria clavellosa, At/. Sp. Jig. vol. i. p. 353. Ag. Syst. p. 206. Hook. Fl. Scot, part 2. p. 105. Oreo. FL Edin. p. 291. Spreng. Syst. Feg. vol. iv. p. 342. Gigartina clavellosa, Lamour. Ess. p. 49. Fucrjs clavellosus, Turn, in Linn. Trans, vol. vi. p. 133. t. 9. Turn. Syn. p. 373. Turn. Hist. Fuc. t. 30. 8m. Eng. Bot. 1. 1203. Hab. On rocks, stones, and parasitical on the smaller Algae near low-water mark; also on the stems of Lammaria, at a greater depth. Annual. Spring and summer. Found on all the British coasts from Orkney to Cornwall. Jersey. Geogr. Distr. Atlantic shores of Europe, from Norway to Spain. Baltic Sea. Mediterranean Sea. Tasmania. Descr. Boot a minute conical disc. Fronds from three to twelve or fourteen inches long, from a quarter of a line to nearly two fines in diameter, with a generally undivided principal stem, which gradually widens from the base to the middle, and then tapers towards the apex. This stem is closely be- set from a short distance above its base to its extremity, with lateral, patent, opposite or alternate, generally distichous branches, of very various lengths, and having a lanceolate outline, which are in like manner pinnated with a second, third or evi-n fourth series of smaller branches or ramuli, the last of which are from one to two or three lines long, spindle-shaped, and sub- acute. Always when young, and very generally in all stages, the ramuli are, like the other parts of the frond, distichous ; but sometimes they are excessively crowded, much divided, and issuing from all sides of the branches. In some varieties the main stem is nearly naked, with a few very long virgate branches, much longer than itself, which are clothed with slightly compound ramuli, half an inch long; in. others the main branches and their divisions are so densely crowded, so excessively compound, and so frequently quadiifarious, that the whole frond becomes a matted ball, so dense that it is difficult to trace its branching. Substance tender, soon decomposing in fresh water. Colour a beautiful pinky red, which becomes rather darker in drying. Chrysymenia clavellosa was first described by Mr. Turner, in the sixth volume of the ' Linnaean Transactions ', where a figure is given, but was known, as this author informs us, to the excel- lent Lightfoot, who proposed to describe it under the specific name bestowed upon it by Mr. Turner. It also appears to have been in some respects known to Hudson, in whose herbarium specimens are preserved. But previously to the publication of Mr. Turner's memoir, it was very commonly regarded as a state of Cliylocladia haliformis, a plant of a different structure, and different ramification. By the younger Agardh it is made the type of a new genus, to which several exotic species are also referable, distinguished from Cliylocladia, under which Dr. Greville included this group, by the absence of internal diaphragms dividing the branches of the frond into distinct joints. This character is accompanied by some difference in habit, and some minor details of structure, and may be admitted as sufficient. But I cannot so readily concur with my friend Agardh in removing Chrysymenia from the Cliondriece to the Coccocarpcre. The nature of the fructifi- cation, and, as it appears to me, the whole structure of the frond are those of Choiidriecc. In Chrysymenia, indeed, the ceramidia are even more perfectly formed than in some species of Cliylocladia. A specimen of Chondrothamnion confertum, DeNot., communi- cated by M. Lenormand, is certainly nothing more than a young and densely branched individual of the present species, such as one commonly finds in spring or early summer. It is a pity that the founders of new species are not always sufficiently careful to observe the changes which these plants undergo at different seasons, and the modifications to which they are subject from circumstances attending then production. Fig. 1. Chrysymenia clavellosa : — of the natural size. i. A small branch, bearing capsules. 3. A section of a ramulus, witli its capsule. 4. A ramulus with tetraspore.s. 5. Tetraspores. . Longitudinal section of the stem. 6. Transverse semi-section of tin 1 same. 7. Longitudinal section of a ramulus, shownng the diaphragms : — all magnified. Ser. CHLORosPEinr .K. Fam. Siphonea. Plate CXIX. BRYOPSIS HYPNOIDES, Lamour. Gen. Char. Fmml membranaceous, filiform, tubular, cylindrical, glistening, branched ; the branches imbricated or distichous and pinnated, filled with a fine green, minutely granuliferous fluid. Bryopsis (Lamour.), — from fipiov, a moss, and ityi?, an appearance. Bryopsis hypnoides; frond slender, very much branched; branches long, repeatedly compound, densely clothed with capillary, elongate ramuli ramellose towards their tips; ultimate ramelli irregularly inserted, erect. Bryopsis hypnoides, Lamour. Jotmi. Bot. 1809. p. 135. t. 1. f. 2. Grev. Alg. Brit. p. 188. Hook. Br. Fl. vol. ii. p. 318. Wyatl, Alg. Damn. no. 81. Harv. Man. p. 146. Hare, in Mack. Fl. Sib. part 3. p. 233. Bryopsis Aibuscula, Ag. Sp. Alg. vol.i. p. 451. Ag.Syst. p. 179. Kate. Phjc. Gen. p. 307. Hab. On rocks, or parasitical on the smaller Alga in submarine tid- pools, in shaded situations, also on Laminaria saccharina, beyond tide marks. Annual. Summer. Not uncommon in many places from Orkney to Cornwall and Jersey. Particularly abundant in parts of the west of Ireland. Geogr. Distr. Atlantic shores of Europe. Mediterranean Sea. Descr. Root composed of branching fibres matted together. Fronds densely tufted, from two to six inches long or more, the principal stems as thick as hogs' bristles, repeatedly and excessively branched, the whole frond baring a broadly ovate or conical outline. Branches crowded, alternate, long and simple, very erect, naked below, above more or less densely clothed with similar irregularly placed lesser branches of much less diameter. These in their turn produce a third series of capillary ramuli, long simple hair-like and very slender, irregularly feathering the apex of the branch from which they spring. Larger specimens only differ from smaller ones in being more re- peatedly divided, the system of branching being the same in all. The sub- stance is very lubricous and flaccid, and soon decomposes in fresh water, the membranous wall of the cells bursting, and discharging a fine granular fluid. Colour when growing, a peculiarly deep, rich green, when dry, be- coming paler, and more yellow. The plant most closely adheres to paper, and the principal stems and branches retain a gloss, as if they had been varnished, but the ramuli are not glossy. This is a more slender plant than B.phnnom, and much more branched ; with more abundant, less regular, and longer ramuli, but specimens sometimes occur which show a very close con- nection between them. On the west of Ireland B. hypnoides is 2g the most abundant, and reaches a size much greater than it attains on the English coast. In sheltered bays, where the broad- leaved variety of Laminaria saccharine/, delights to grow, that plant is often seen covered with thick bunches of this Bryopsis, of an extraordinary size and luxuriance. These arc never ex- posed at low water, and can only be reached in a boat ; but in shady channels and pools between tide marks, even at some dis- tance above the low water limit, specimens of nearly equal size, attached to smaller Algae, are frequently met with. Professor J. Agardh in his excellent work on the Alga? of the Mediterranean, considers our B. hypnoides to be merely a more advanced state of B. plumosa. It is possible that he maybe correct in this conclusion, and I confess that I have sometimes been inclined to a similar opinion, though I do not consider that I have before me sufficient data to warrant my adopting this view of the subject, in opposition to the observations of able natu- ralists, who have decided in the opposite way. The question is, however, open to further enquiry, and I trust, before the con- clusion of this work to be able to speak more decidedly. At any rate the present figiue will be useful to contrast with that given at Plate III. of the B. plumosa of British writers. Fig. 1. Bryopsis hypnoides: — the natural «'.-(•. 2. Apex of a branch, with its lesser branches. 3. Part of one of the lesser branches, with ramuli : — both magnified. Efer. RlIODOSPKKMK.K. I' : ""- ' ' >' „lie(B. Plate CXX. ./. CALLITHAMNIO N FLORI DULUM, Ag. Gen. Ciiae. Frond rosy or brownish-red, filamentous; stem either opake and cellular, or translucent and jointed ; branches jointed, one-tubed, mostly pinnate (nuvh dichotomous or irregular) ; dissepiments hyaline. i plants; 1, external tetraspores, scat- tered along the ultimate brauchlets, or borne on lilt !e pedicels; 2, roundish or lobed, berry-] ) seated on the main branches, and containing numerous angular spores. Callithamxion (Lungb.), — from raAAir, beautiful, and Oafwiov, a little shrub. CiZLHfBAMmos Jloridulum ; tufts very dense, more or less globose, fasti- giate ; filaments slender, dichotomous or alternately branched, the branches few, very erect or appressed, long, simple, straight; articu- lations thrici broad, cylindrical; tetraspores oval, borne on very short, ei - ranged in a secund manner, along the upper branches. ( Ai.i.iTiiAMMON floridulum, Ag. Sp. Alg. vol. ii. p. 188. Han. in Hoot. Br. M. vol. ii. p. 348. Hair. Man. p. 116. Wyatt, Alg. Damn. no. 219. Phjc. Gen. p. 371. Trentepohlia floridula, Han-, i.i Mack. Fl. Hib. part 3. p. 218. Conferva floridula, Dillw. Conf. Suppl. t. f. Hab. On sand-covered rocks, near low-water mark, at all seasons. Peren- nial ? March and April. Abundant on the Galway coast, where it wa< first observed by Mr. J. T. Maekay. Also on the Clare and Kerry coasts, and on the east coast of Ireland. Antrim, Dr. Scott. Orkney. /,', v. J. II. Pollt ■■/■ n. Land's End, Mr. Ralfs. Geogr.Distr. Coast of France. Descs. Moments of equal diameter throughout, very slender, silky, closely packed together in dense, more or less fastigiate, roundish tufts, dichoto- mously or irregularly branched ; branches few, lc id very straight, the lower ones longest, the rest gradually shorter. Hamuli few or none, closely pressed to the branches. Tetraspores oval on short pedicels, secnndly disposed along the branches. Joints fully thrice as long as broad. dull pink, becoming more or less purple in drying, the bases fre- quently fading to a dull" green. Substance membranaceous imperfectly adhering to paper. An exceedingly abundant species on the west coast of Ireland, covering a large extent of rock with its hemispherical, densely matted and aggregated cushions. At the close of summer great quantities of these, which are called figs by the country people, are washed mi shore, and collected as manure,, though inferior in strength to many other marine plants. The fructification was discovered by Mr. Ralfs, in the year 1840. Fig. ./. Callitii amnion floridciam : — of the natural she. 2. Portion of a filament. 3. Apex of a branch in fruit, i Section of a branch, with tetraspores : — all More or less magnified. Plate CXX. B. CALLITHAMNION ROTHII, Lyngl. Callithamnion Rothii; widely spreading, densely tufted; filaments very slender, short, erect, diehotomous or irregularly branched; branches long, straight, appressed ; articulations twice as long as broad ; tetra- spores clustered, borne on short, subtenninaL corymbose ramuli. Callithamnion Rothii, Lyngl. Hyd. Ban. p. 129. t. 41. Ag. Syst. Jig. vol. ii. p. 185. Hare, in Hook. Br. Fl. vol. ii. p. 317. Han. Man. p. 116. (f'yatt, Jig. Danm. no. 188. Endl.Srd Supply .31. Kilt:. Pliyc. Gen. p.471. Ceeajiium Rothii, Berk. Gl. Br. Jig. t. 20. Trentepoiilia Rothii, Han. in Mack. Fl. Hib. part 3. p. 218. Conferva Rothii, Linn. Syst. Nat. vol. vi. p. 1806. Dillw. Conf. t. 73. E. Bot. t. 1702. Jurff. Jig. Dec. no. 10. Conferva violacea, Roth. Cat. Bot. vol. i. p. 190. 1. 1. f. 1. Fl. Germ. v. iii. part 1. p. 525. /3. purpurea; filaments very minute, forming continuous velvetty patches, slightly branched. Callithamnion purpureiun, Han. Man. p. 116. Trentepohlia purpurea, Jg. Syst. p. 36. Han-, in Hook. Br. Fl. vol. ii. p. 3S2. Han. in Mack. Fl. Hib. part 3. p. 218. Byssls purpurea, E. Bot. 1. 192. Conferva purpurea, Dilhc. t. 43. Hab. Spreading over the surface of rocks, about half-tide level. £. on maritime rocks, within the influence of the spray, but beyond the reach of ordinary tides. Perennial. Winter. Geogr. Distr. Atlantic shores of Europe. Baltic Sea. East coast of North America. Descr. Filaments from a line to half an inch in height, very slender, densely packed together in extensive velvetty patches, of a deep red or purplish red colour. Branches few, simple, and very erect, the lowest longest, gene- rally bare of ramuli. Tetraspores two to four, or frequently three together, on short pedicels, growing from the uppermost joints of the branches. Joints twice as long as broad. Substance membranaceous, more or less per- fectly adhering to paper. A smaller and more slender plant than the preceding, with shorter joints, and well characterized by the difference in fructi- fication. I have ventured, I trust not without sufficient warrant, to unite to C. Rothii the old Conferva or Byssus purpurea, which I have long regarded as a stunted form, whose characters depend on the situation in which it is found growing. In this opinion I tun supported by Mr. Rails, an accurate and close observer, who has had the best opportunities of investigating the subject. /;. Callithamnion Rothii: — of the natural size. 2. Portion of a filament. 3 \ju\ of a branch in fruit. 4. Section of a branch with clusters of tetraspores : — all more or less magnified . ALPHABETICAL INDEX VOL. I. {The synonyme* ft alios.) Plate Agardhia adherens, Cabrera ... 35 A. dichotoma, Cabrera 93 i tculi ntum, Rory 79 AglaiopJiyllttm Butiiiinwiviiti ,Ya\A\. . . 23 Alaria csculenta, Grev 79 Alcyonidium faillatum, Lamx 68 Ahidiiun scorpioides, J. Ag 48 Anabaina marina, Breb 113 A. Arthroeladia villosa, Duby 64 Asperococcus bn/losiis, Lamx 11 cornpressus, Griff. ... 72 rvffosm /3, Duby. ... 11 Turneri, Hook 11 Bangia atro-purpurea, Ag 96 fusco-purpurea, Lyngb 96 Johnstoni, Grev 54 B. versicolor, Kg 96 oiridis, Oed 54 B. Batraehospermum attettuatum^Bon. . . 106 Belonia torulosa, Cami 113 A. Bonuemaisonia asparagoides, Ag. . . 51 Bostrichia scorpioides, Mont 48 Bryopsis Arbuscula, Ag 119 hypuoides, Lamx 119 Lyngbycri, ~F\. Dan 3 plumosa, Ag 3 Byssus purpurea, Sm 120 B. Callitliamniou floccosum, Ag 81 lloridulum, Ag. . . . 120 A. gracillimum, Ag 5 niidtijiduhi, Kg 27 Plate Callitliamniou noduloaum, Kg 106 Plnmula, Lyngb 81 Pol/exfenii, Harv. ... 81 purpureum, Harv. . 120 B. Rothii, Lyngb 120 B. seirospermum, Griff. . . 21 Iripinnatiim, Ag 77 versicolor, Harv 21 Calothrix fascicidata, Ag 58 A. pannosa, Ag 76 scopnlorum, Ag 58 5. Carmichaelia attenuate, Grev 25 Carpoinitra Cabrera 1 , Kg 14 Catenella Opimtia, Grev SS Ceramium asparagoides, Both 51 I H ' \!7 diaphanum, 0, Wyatt. . . 90 equiselifolium, DC 67 filamentosum, Ag 16 Mum, Roth 107 incurvum, DC 85 nodosum, Griff. & Harv. . 90 oeeUatani, Ag 40 pennatum, Oed 87 Plocamium, Roth 41 phimosum, Both 80 rujidulum, Griff. & Harv. . 90 scopariuai, Roth 37 tidjercidosiini. Roth 69 verticittatum, DC 33 nerticiUatum, Duel 21 ALPHABETICAL INDEX Clurtoilrrma pelMtum, Kg 117 Chatophora multifida, Hook 36 pellita, Lyngb 117 vermiculata, Hook 31 Chatopteris pltmoms, Kg 87 Chatospora Wigghii, Ag 38 Chondria r/nrellosa, Ag 114 Op u a tin, Hook 88 uni'is, Ag 118 pinnatifida, Ag 55 purpurascens, Grev 59 Chondrothammon elaveUosum, Kg. . . 114 confertum, De Not. . 114 Chondrus Brodiai, Grev 20 eelHcus, K 1 />. intertexta, Roth 102 A. intricata, Grev 54 B. Kaneana, Me' Calla 86 lanosa, Roth 6 majuseula, Dillw 62 Melagomum,/r ( -M-J/o//>-. 99 A. multifida, ffuds 27 phyllum, Tioth 33 pennata, Sin 87 ata, Br '-i" pulvinata, Roth 120 B. purpurea, Dillw 120 B. is, Griff 12 refracta, Roth 21 rhizodes, Ehr 70 Rothii, Turn 120 B. Eudolphiana, Ag 80 scoparia, Linn 37 seopulorum, Web. 5*. Mohr. 58 B. Conferva sguarrosa, Oed 50 tortuosa, Dilltc 54 ./. ulothrix, Lyngb 54 B. verrucosa, Sm 70 verticillata, Lyngb 33 - Huds 64 ii a, Both. . ; . . .* 120 B. Oorallopm dichotoma, Suhr 69 Crouania attenuata, /. Ag 106 Oruoria deusta, Aiesch 98 pellita, Fries 117 Outleria multifida, Orev 75 rculata, Dne 89 Dystocia* eu.ru, Kg 117 Cystoseira foeniculacea, Grev 122 granulata, .l, v. Good. & Woodw 79 tetragonus, Good. & Woodw . . 79 mm, Buds 93 tuberviilalns, Huds 89 tuberculatus, Lightf. 116 "/■/■/ v, Gm US r, rrucomu, Buds 65 cer/ici/la/iis, \\ nil" 33 Fucus Wigghii, Turn 38 Furcellaria fastigiata, Lamx 94 tycopodioides, Ag 50 himbricoMs, Eg 96 lumbricalis, Lamx 91 rotunda, Lyngb 95 Gastridium clavellosum, Lyngb 114 filiforme, Lyngb 59 Opuntia, Lyngb 11 ovale, Grev 118 Gastridium purpurascens, Lyngb. ... Ill ovale, Kg 118 Gelidium corneum, Lamx 53 opifolium, Lamx. ... 61 neglectitm, Bory 100 pinnaMfidum, Lyngb 55 rostral u.m, Griff 83 Gigartina acicularis, Lamx 101 cupillaris, Lamx 57 clavellosa, Lamx Ill confervoides, Lamx 65 flagelliformis, Lamx Ill Crriffitlmce, Lamx 108 lubrica, Lyngb 57 lycopodioides, Lamx 50 Opuntia, Lamx 88 pedumcuUxta, Lamx 56 pilosa, Lamx 88 pinastroides, Lyngb 85 purpurascens, Lamx 116 rotunda, Lamx 95 vermicularis, Lamx 118 Ginannia fuicellata, Moni 69 Gloiosiphonia capillaris, Carm 57 [ hrai ilaria confervoides, Grev 65 multipartita, /. Ag 15 poh/carpa, J. Ag 16 purpurascens, Grev 116 ( hrateloupia tilieina, Ag 100 porracea, Kg 100 Griffithsia Devoniensis, IFarv 16 equisetifolia, Ag 67 'tifida, Ag 27 nodulosa, Ag 106 Grymnogongrus Griffitnsise, Mart. . . 10S Salarachnion Ugulatum, Kg 112 Halidiya siliquosa, lyngb 66 Haliseris dichotoma, Sprang 103 polypodioides, Ag 19 Haloglossum Griffithsianum, Ki;-. ... 72 HalopUhys pinastroides, Kg 85 Hdlurus equisetifolius, Kg 67 Ilalymenia edulis, Aj; 97 elongata, Ag 112 filiformis, Ag 59 furcellata, Ag '• . . 69 Ilalymenia ligulata, Ag 112 Opuntia, Ag 88 purpurascens, Grev 59 reniformis, Ag 13 Helicothamnwn scorpioides,Kg 48 Eelminthocladia vermicularis, Harv. 31 vireseens, Harv. ... 82 Hehninthora muliifida, Kg 36 Hildenbrandtia rubra, Menegh 98 Himanthalia lorea, Lyngb 78 Hormoceras nodosum, Kg 90 Wutchinsiafilamentosa, Ag 46 furcellata, Ag 7 obscura, Ag 102 A. ocellata, Ag 10 pulvinata, Ag 102 B. Hypnea confervoides, J. Ag 65 purpurascens, Harv 116 Sypoglossum rttscifolium, Kg 26 Woodwardii, Kg 2 Iridaea edulis, Bory 97 reniformis, Bory 13 Kalymenia reniformis, /. Ag 13 Laminaria cuneata, Suhr 45 debilis, Ag 45 esculenta, Lyngb 79 Fascia, Ag 45 ligulata, Hook 115 papyrina, Bory 15 Lamourouxia turgidula, Bonn 7 Laurencia pinnatifida, Lamx 55 puncttfbrmis, Lyngb 41 B. TAthophyllum decussatum, Phi] 73 mm, l'hil 73 ALPHABETICAL INDEX Lithothamnium crassmn, Phil 74 Lomt ntaria Opuntia, Gaill 88 ovalis, r.iidl - . . 118 ubo, Duby -12 reflexa, Chauv 42 Lophttra lycopodioides. Kir 50 Lyngbya crispa, Ag 62 majuscula, i/«>T 62 Melobesia agaricifonnis, Harv 73 decussata, End! 73 expansa, Eudl 73 fasciculata, 7/«/'t' 74 Mertemia tripinnata, Grat 77 Mesogloia affinis, Berk 82 attenuata, Ag 106 Baluui, Carat 36 capillar!*, Ag 57 divaricata, Kg 17 divaricata, Ag 110 gracilis, Carni 82 Hornemanni, Suhr 82 Hudsoni, Ag 112 Hudsoni, Harv 110 moniliformis, Griff 106 mullifida, Ag 36 vermicularis, ^'// 31 virescenSj C«w« 82 Zostera, Aresch 82 Microcladia glandulosa, G/vc 29 \fillepora agariciforvm, Pall 73 coriacea, L 73 decussata, F.llis 73 /; wiculata, Lam 74 torfuosa, Esp 73 Myclom : . _ 69 Myriactw pulvinata, Kg 28 ^/. Myrionema Leclancherii, fiarc. ... 41 .7. punctiforme, flare. ... 41 .B. velutmum, End] 28 5. Myriotricbia clavsformis, Hare. . . . 101 Nacearia Wigghii, £,«// 38 Nemahon lubrieum, Duby 36 niultitidum, ■/. .7jr 36 Nitophyllum Bonnemaisoni, Gyve. . 23 versicolor, //;/;■(• 9 Plate. Nullipara agariciformis, Blfrinv .... 73 fasciculata, Blainv 74 Odontbalia dentata, Lyngb 34 Oscillatoria wopulorwm, Ag 58 B. littoralis, Carm 105 A. spirabs, Carm 105 B. subsaha, Harv 105 B. Padina atomaria, Mont 1 deust a, Hook 98 Mediterranea, Bory 91 Pavonia, Lamx 91 phasiana, Bory 1 Peyssonelia Dubyi, Crouan 71 Phycolapathum debile, Kg 8 Phycoseris Lima, Kg 39 Pkyllacaiitbo Boryana, Kg 60 Phyllopbora Brodisei, •/. Ag 20 Physactis lobaia, Kg 68 Physocaulon Mackaii, Kg 52 Ploeamiiun amphibium, Lanix 48 »j Lamx 51 Binderianum, Kg 44 coccineurn, Lyugb 44 ft m ;>,■,■'>■„;. Kg 44 'byaniim, Kg 41 phimosum, Lamx 80 vulgare, Larnx 44 Plocaria multipartita, 'Efodl 15 polycarpa, Eudl 15 Pollicipora agariciformis, Ehr 73 Polyides Oriffitksia), Gaill 108 lumbricalis, Ag 95 rotundas, Grev 95 \\A\ aphonia furcellata, flora 7 arpa, Harv. . . 102 B. obsenra, /. Ag 102 A. pulvinata, Spreng. . . 102 B. Richardsoni, Moot. .. 10 Porpbyra laciniata, Ag 92 umtnlicalis, Ag 92 Ptilota pluraosa, Ag 80 Punctaria latifolia, Gree 8 Pycnopbycus tuberculatus, Kg 89 RalMa deusta, Berk 98 Rhodymenia bilida, Grec 32 Rhodymniia polycarpa, Grev 15 renifbrms, Hook 13 rodrata, .). Ag 83 Bhodomela dentata, \g 34 lycopodioides Ag 50 ■pi n a st rohhs, Ag 85 scorpioides, Ag 4S Wiynchococcm coronopifolim, Kg. . . 61 liiuilaria liiillu/u. lVrk 68 Leclancherii, Chauv. ... 41 A. multifidn, Web. & Mohr. . 36 nitida, Ag 68 Opuntia, Sm 88 rirmiciiliita, Sm 31 Zosterce, Mohr 82 Rytiphlsea pinastroides, Ag 85 Sarcop/iyllis lobata ?, Kg 13 Sargassum bacciferum, Ag 109 Scytocldoria nitida, Harv 6S Scylosiplwti crec/us, Lyngb 43 Filum, Ag 107 olivascem, Carm 25 Seirospora Griffithsiana, Harv 21 Solenia attenitata, Ag 25 clatkrata, var. Ag 43 erinita, Ag 25 Lin:a, Ag 39 Spermaiochnus rhizodes, Kg 70 Spermosira btorea, Kg 113 C. Sphacelaria disticha, Lyngb 37 plumosa, Lyngb 87 scoparia, Lyngb 37 scoparioides, Lyngb. ... 37 velutina, Grev 28 B. Spbarococcus acicularis, Ag 104 bifidus, Ag 32 Brod'uei, Ag 20 confervoides, Ag. '. . . 65 corneus, Ag 53 coronopifolius, Ag. . . 61 Crispin, Ag 63 GriffitAsiai, Ag 108 multipartitus Ag. ... 15 polycarpus, Ghrev. ... 15 p/'i/mrasceiis, Ag. . . . 116 Sphrerozyga Carmichaclii, Harv. . 113 A. rinte Sphncrozyga Thwaitcsii, Harv. .. 113 5. Spirillum rupexlri', I lass 105 B. Spirulina tcnuissima, Kg 105 C. S/iw/giortirpiix riilnnilux, (irev 95 Spongodium com inline, Bory 39 tomentosum, Lamx 93 Sporochuus aculeatus, Ag 49 Cabrera, Ag 14 lig ii la I iis, Ag 115 multifidus, Spreng 75 peduncidatus, Ag 56 rhizodes, Ag 70 villosus, Ag 64 Spyridia crassiuscula, Kg 46 filamentosa, Harv 46 nndiuscula, Kg 46 setacea, Kg 46 Stilophora erinita, Ag ; . . 25 rhizodes, J. Ag 70 Striaria attenuata, Grev 25 Stypocaidon scoparium, Kg 37 Stypopodium atomarium, Kg 1 TrentepoMia Jtoridula, Harv 120 A. purpurea, Ag 120 B. Bothii, Ag 120 B. Trichocladia ivrmicularis, Harv. ... 31 virescens, Harv '■ 82 Tylocarpus Griffithsiie, Kg 108 tmtaculatus, Kg 108 Ulva articulata, ft Huds 88 alomaria, Woodw 1 attenuata, Nac 25 eucidlata, Cav 91 dickotoma, Huds 103 edulis, DC 97 filiformu, Wahl 59 fnrcellata, Turn 69 in/ 1 rri'pta, Poir 69 laeiniata, Lyugb 92 ligii/a/a, Woodw 112 lingii/ata, DC 2 Linza, L 39 multifida, Sm 75 Pavonia, L 91 plumosa, Huds 3 polypodioides, DC 19 ALPHABETICAL INDEX TO VOL. I. Diva rubens, Iluds 110 rubra, Hiuls 112 serrata, DC 1 Turneri, Dillw 11 umbilicalis, Sni 92 WormskioMia Hypoghsmm, Spreng. 2 ruscifolia, Spreng. ... 26 Wrangelia multifida, /. Ag 27 Plate. Zonaria atomaria, ^.g 1 deusta, Ag 98 dichotoma, Ag 103 lineolata, Ag 25 multifida, Ag 75 Naccariana, Ag 25 Pavonia, Ag 91 A LIST OP THE BRITISH MARINE ALGyE ARRANGED SYSTEMATICALLY. Several changes having been recently made in the distribution of the Algffi into Families, the following List is given for the use of those to whom these alterations may be unknown, for the purpose of enabling them to arrange their collections in systematic order. Species in which the native locality is doubtful, are marked with an asterisk (*) ; those which are doubtful as species and require further examination, are marked with a cross (f). Series 1. Fam. 1. FUCE.E. I. Sargassum. * 1. vulgare, Ag. * 2. bacciferum, Ag. II. Cystoseira. 1. ericoides, Ag. 2. granulata, Ag. * 3. barbata, Ag. i. fa'niculacea, Grev. 5. fibrosa, Ag. III. Halidrys. 1. siliquosa, Lyngb. IV. Pycnophyctjs. 1. tubereulatus, Kg. V. Fucus. 1. vesiculosus, L. 2. ceranoides, L. 3. serratus, L. 4. nodosus, L. 5. Mackaii, Turn. 6. canaliculatus, L. VI. HlMANTIIALIA. 1. lorea, Lyngb. MELANOSPERMEjE. Fam. 2. LAMINARIE^. VII. Alaria. 1. esculenta, Grev. VIII. Laminaria. 1. digitata, Lx. 2. bulbosa, Lx. 3. saccharina, Lx. t 4. Phillitis, Lx. 5. fascia, Ag. Fam. 3. SPOROCHNOIDE.E. IX Desmarestia. 1. ligulata, Lx. 2. viridis, Lx. 3. aculeata, Lx. X. Sporochnus. 1. pedunculatus, Ag. XL Carpomitra. * 1 . Cabrera, Kg. XII. Arthrocladia. 1. villosa, Duby. SYSTEMATIC LIST OF Fam.4. DICTYOTEiE. XIII. CUTLEBIA. 1. multifida, Grev. XIV. IIaliseris. 1. polypodioides, Ag. XV. Padina. 1. Pavonia, Lx. XVI. Padinella. 1. parvula, Aresch. XVII. DlCTYOTA. 1. dichotoma, Lx. 2. atomaria, Grev. XVIII. Stilopiioea. 1 . rhizodes, /. Ag. 2. Lyngbysei, /. Ag. XIX. Dictyosiphon. 1. feiiiculaceus, Grev. XX. Striaria. 1. attenuata, Grev. XXI. PtJNCTARIA. 1. latifolia, GrTv. 2. plantaginea, Grev. 3. tenuissima, Grev. XXII. Asperococcus. 1 . compressus, Griff. 2. Turned, Hook. 3. echinatus, Grev. XXIIT. Chlorosiphon. 1. pusilius, Hurv. 2. LamiuaricC, Harv. XXrV. Chorda. 1. Filiun, Lx. 2. lomeutaria, Grev. Fam.5. ECTOCAEPE.E. XXV. Cladostephus. 1. verticillatus, Lyngb. 2. spongiosis, Ag. XXVI. Sphacelaria. 1. filicina, Ag. 2. Sertularia, Bonn. 3. seoparia, Lyngb. 4. plumosa, Lyngb. 5. cirrhosa, Ag. 6. fusca, Ag. 7. radieans, Harv. f 8. olivacea, yty. f 9. racemosa, Grev. XXVII. Ectocarpvs. 1. littoralis, Lyngb. 2 .dificulosus, Lyngb. 3. fasciculatus, Harv. 4. Hincksise, Harv. * 5. scorpioides, Harv. * 6. spinescens, Harv. * 7. longifructus, £arp. * 8. ampliibius, Harv. 9. tomentosus, Lyngb. 10. crinitus, Cam. 11. pusilius, Griff. 12. simplex, Ag. 13. villum, i/c/T. * 14. distortus, Carm. 15. granulosus, Ag. 16. spbaerophoras, Carm. 17. brachiatus, Han. 18. Mertensii, Jfy. XXVIII. Myriotrichia. 1. clavsefomiis, Harv. 2. filifonnis, LLarv. Fam. 6. CHORDARIE.E. XXIX. Myrionema, 1. strangularis, Grev. 2. Leclanelierii, Harv. 3. punctiforme, Harv. 4. clavatuui, Harv. XXX. Elachistea. 1. fucicola, Fr. 2. flaccida, Fr. 3. curta, Aresch. 4. pulvinata, .Harp. (attenuata.) 5. stellulata, //arc. 6. scutulata, J 1 / - . 7. velutina, Fr. XXXI. Ralfsia. 1. deusta, Berk. BRITISH MARINE ALG.E. XXXII. Leathbsia. 1. tuberifonnis, Gray. ra marina, kg.) 2. Berkleyi, lion-. XXXIII. Mesogloia. 1. vermicularis, Ag. 2. virescens, Carm. 3. Griflitlisiana, Grev. XXXIV r . Chordaria. 1 . flagelliformis, Ag. 2. divaricata, Ag. Series ;>. RHODOSPERVI EM. Fam. 7. CERAMIK .V. Callitiiammcn. 1. Plumula, Lyngb. 2. cruciatum, Ag. 3. floccosum, Ag. 4. Turneri, Ag. t, Ag.) 5. Pluma, Ag. 6. barbatum, /. Ag. (?) 7. Arbuscula, Lyngb. 8. Brodiaci, Han. 9. tetragonmn, Ag. 10. Harveyanum, J. Ag. 11. tetricuin, -4(7. 12. Hookeri, Ag. [apinomm, Harv.) 13. roseum, Ag. 14. byssoideum, Am. 1 5 . polyspenmrm, Ag. (Grevillii, Harv.) f 16. faseieulatum, Harv. 17. Borreri, Ag. 15. triphmatuin, Ag. * 19. aftine, Ban. 20. gracillimum, ^r. SI. thuyoideum, Ag. 22. corymbosum, -/y. (versicolor, Ag.) 23. spongiosum, 77art\ 2 1 . pediceflatum, Ag. 25. flaridumm, ./;/. 26. Rnthii, Lyngb. ( purjmreum, Harv.) ■y, . mesorarrpum, ' * 28. sparsuin, Harv. 29. Daviesii, Ag. (secundatum, Ag.) (lannginosum, Lyngb.) XXXVI. Seirospora. 1. Griffithsiana, Han. XXXVII. Wrangeha. I. multifida, /. Ag. XXXVIII. Griffithsia. 1. equisetifolia, Ag * 2. sinipucifilum, Ag. 3. barbata, Ag. 4. Devomensis, Han. 5. corallina, Ag. 6. secundiflora, /. Ag. 7. setacea, Ag. XXXIX. Spyrldia. 1. filamentosa, Han. XL. Ceramicm. 1. ciliatum, Duclu:. S. acanthonotum, Carm. 3. echionotum, /. Ag. 4. flabelligerum, .7. ./. cristata, ' 6. ciliata, Grev. BRITISH M.UU\r Mi. 1 7. jubata, Grev. 8. pahnata, Grev. (sobolifera, Grev.) Fam. 14. l»i:i,r.sSERIEj;. 1.XIW Plocamium. 1. coccineum, Lyngb. ].\X. Pei.esseria. 1. sanguinea, Lx. 2. sinuosa, Lx. 3. alata, /.'■. 4. angustissiina, Griff. 3. Hvpoglossum, Lx. 6. ruseifolia, Lx. LXXI. NlTOPIIYLLUM. 1. punctatum, Grev. 2. Hillia?, Grev. 3. Bonnemaisoni, Grev. 4. Gmelini, Grev. 5. laceratum, Grev. * 6. versicolor, Harv. Fam. 15. CHONDU1E.E. LXXII. BoNNEMAISOXIA. 1. asparagoides, Ag. LXXIII. Lalbexcia. 1. pirmatifida, Lx. * 2. hybrida, Lenorm. 3. obtusa, Lx. 4. dasyphylla, Lx. 5. termissima, Lx. LXXIV. Chkysimema. 1. clavellosa, /. Ag. LXXV. Chylocladia. 1. ovdis, ILook. 2. kalilbrmis, Hook. * 3. rcflexa, Lenorm. 4. parvnla, Hook. 5. articulata, LLook. Fam. Hi. COliALLIM'.h. LXXVT. Coram. ina. 1. officinalis, L. 2. elongata, Ml. §■ Sol. 3. squamata, Ml. $r Sol. LXXVII. Jama. 1 . rubens, Lx. 2. corniculata, Lx. LXXVIH. Melobesta. 1. polymorpba, L. 2. calcarca. ML. §• Sol. 3. fasciculata, Lam. 4. agariciformis, Lam. 5. Liclieiiil'oraiis, Due. 6. nierubranacea, Lx. 7. farinosa, Lx. 8. verrucata, Lx. 9. pustulata, Lx. Fain. 17. RHODOMELK I LXXTX. Odonthalia. 1. dentata, Lyngb. TAXX. Ehodojiela. 1. subfusca, Ag. 2. lycopodioides, Ag. LXXXI. Bostrichia. 1. scorpioides, Mont. LXXXII. Eytiphl.ea. 1. pinastroides, Ag. 2. complanata, Ag. 3. tbuyoides, Harv. 4. fruticulosa, Hare. LXXXIII. Polysipiioxia. 1. parasitica, Greo. 2. subulifcra, Harv. 3. spmulosa, Grev. 4. atro-rubescens, Grev. 5. nigresceus, Grev. (jmrpuratcens, Harv.) (atro-purpurea, Moore.) {affinis, Moore.) (5. furcellata. Harv, ] . Fastigiata, Greo. * 8. Richardsoni, Hook. 9. Griffithsiana, Hare. * 10. Carmichaeliana, Harv. 1 1. Brodisei, Grev. brillosa, Greo. SYSTEMATIC LIST OF 13. violacea, Grev. ? 14. variegata, Ag. 15. Grevillii, Harv. 16. fibrata, Harv. * 17. stricta, Grev. 18. pulvinata, Ag. 10. obscura, Ag. 30. formosa, Suhr. 21. urceolata, Grev. 22. elongata, Grev. 23. elongella, Harv. 24. byssoides, &ra>. LXXXIV. Dasya. 1. coccinea, Ag. 2. ocellata, Harv. 3. Arbuscula, Ag. Series 3. CHLOROSPEBME.E. Fain. 18. SIPHONED. LXXXV. Codium. 1. Bursa, Ag. 2. adherens, .^y. 3. tomentosurn, Stack. 4. amphibiuni, Moore. LXXXV L Bryopsis. 1. plumosa, las. 2. hypnoides, Z.r. LXXXYII. Yauchekia. 1. submarina, 2?«-&. 2. marina, Li/ngb. 3. velutina, ^y. Fam. 19. COXFERVEjE. I, XXXVIII. Cladophoea. 1. Brownii, Harv. 3. peUucida, Ay. 3. rectangularis, &W^". t. Macallana, Harv. 5. Ilutfliiiisiiu, //«rr. 6. diffusa, Ay. * 7. inula, ffarv. 8. rupestris, Ay. 9. ]ati\ irens, Ay in. flexuosa, Dttko. 11. gracilis. f.V;//" 12. Rudolphiana, Ay. 13. refracts, Ay. 1 I. albida, Huds. ].V lanosa. Ay. 16. unciabs, Harv. 1 7 . arcta, Kg. 18. glaucescens, GWy 7 '. * 19. faleata, Harv. LXXXIX. Rhizogonum. 1. riparium, Kg. XC. Conferva. 1. arenicola, Berk. 2. arenosa, Carm. * 3. litorea, Harv. 4. Linum, Roth. 5. sutoria, Berk. 6. tortuosa, Dillto. 7. implexa, Dilhc. 8. mclagdnum, 7F. §• M. 9. ;erea, ZW/V 10. ooUabens, Ag. 11. bangioides, Z/an\ 1 2. Youngana, Dillw. Fam. 2d. 1LYACE.E. XCI. FORPIIYUA. 1 . laciniata, Ag. 2. vulgaris, ^-iy. (linearis, Grev.) 3. miuiata, --/y. XCII. BANGIA. 1. fusco-purpurea, Lgngb. 2. ciliavis, ('arm. 3. elegans, CSoar. BRITISH MARIN K AI.C.K XC1II. Enteromorpha. 1. Cornucopia, Carm. i. intestinalis, Link. 3. compressa, Orev, * 4. Linkiana, Orev. 5. erecta, Hook. 6. clathrata. Greo. *7. Hapkirkii, M 'CaUa. * 8. ramiilosa, Uook. 9. percursa, Hook. XCIV. Ulva. 1. latissima, L. 2. Lactuea, Z. 3. Liiiza, L. Fam. 21. OSCILLATOR-IE.^. XCV. Rivularia. 1. nitida, Ag. 2. applanata, Carm. 3. atra, Roth. 4. plicata, Carm. XCVI. ScHlZOTHRIX. 1. Cresswellii, Harv. XCV1I. Oalothrix. 1. eonfervicola, Ag. 2. luteola, Grev. 3. scopulorum, Ag. 4. fasciculata, Ag. 5. pannosa, ^. 6. hydnoides, Harv. * 7. cnespitula, Harv. XCV III. MlOKOCOLEUS. 1. marinus, Harv. 2. aiiguiiius, Harv. XCIX. Lyngbya. 1. majuscula, Harv. 2. ferruginea, ^ty. 3. Carmichaelii, Harv. 4. flacca, /Zaro. 5. speciosa, Carm. C. Oscillatoria. 1. litt oralis, Carm. 2. spiralis, Carm. CI. Spirulina. 1. tenuissima, Kg. Fam. 22. NOSTOCHINEJL CII. Monormia. 1. intricata, Berk. CIII. Sph.erozyga. 1. Carmichaelii Harv. 2. Thwaitesii, Harv. 3. Broomei, Thw. 4. Berkeleyi, Tim. 5. Ealfsii, 2%w. CIV. Spermosira. 1. litorea, Kg. *7fC&