V ORGANIZED 1873 VOLUME XXXIX JULY 1920 INCORPORATED 1891 NO. 3 REPRINTED FROM THE TRANSACTIONS OF THE AMERICAN MICROSCOPICAL SOCIETY PROTOZOA OF DEVIL’S LAKE COMPLEX, NORTH DAKOTA C. H. EDMONDSON Pages 167-198 PUBLISHED QUARTERLY BY THE AMERICAN MICROSCOPICAL SOCIETY MENASHA, WISCONSIN ANNUAL SUBSCRIPTION $3.00 SINGLE COPY $1.00 DOUBLE NUMBERS $2.00 ■ - / ■;; i W' - ? V f" - - 3 , S- '. Fin\e; PROTOZOA OF THE DEVIL’S LAKE COMPLEX, NORTH DAKOTA BY Charles Howard Edmondson, Ph.D, University of Oregon^ CONTENTS Page 1. Introduction 167 2. Taxonomy 171 3. Experiments 190 4. Summary and Conclusions 193 5. Index 195 1. Introduction Several reports previously issued^ have described the physio- graphic and chemical characteristics of Devil’s Lake situated in Ramsey County, North Dakota. In a recent paper Dr. R. T. Young,* of the University of North Dakota, has indicated something of the possibilities and limitations of the lake from a biological point of view, as well as the general scope of the work already accomplished in that direction. It will only be necessary, therefore, to set forth a few of the specific features of this water area which may have some bearing on the report to follow. ^ The investigations included in this report were carried on at the State Biological Station of North Dakota. 2 Biennial Report of the State Biological Station of North Dakota, 1911-12. Pope, T. E. B. Devil’s Lake, North Dakota, a study of physical and biological conditions, with a view to the acclimatization of fish. U. S. Bureau of Fisheries Docu- ment 634, 1908. Simpson, H. E. The Physiography of the Devil’s-Stump Lake Region, North Dakota. Sixth Biennial Report of the State Geological Survey of North Dakota, 1912 . Upham, W. The Glacial Lake Agassiz, Mon. 25, U. S. Geological Survey, 1895. ® Young, R. T. The Work of the North Dakota Biological Station at Devil’s Lake. The Scientific Monthly, December, 1917. 168 CHARLES HOWARD EDMONDSON, PH.D. The origin of Devil’s Lake may be traced to glacial action and at an early period the united waters of this region must have covered a very large area. In 1883 the United States Geological Survey esti- mated the area of the lake at 125 square miles, and at that time it had a depth of 60 feet, while at the present time its area is about one-half and its maximum depth one-third that of thirty-seven years ago. By a gradual drying up of the lake and the establishment of certain roadways, it has been divided into four larger bodies of water and a number of smaller ones. These four divisions have been designated as the Western Section, Main Lake, East Lake and Lamoreau Bay. To the southwest of Lamoreau Bay is situated Stump Lake, in times past connected with the main body and included in the complex for purposes of this report. Within recent years Big and Little Mission Lakes have been entirely cut off from the main lake at its southeast border, and parallel with the southwest border of the main lake are a number of smaller lakes, which at one time were parts of the common body of water. The concentration of the water of these lakes ap- proaches or exceeds that of the main lake. Locally they are desig- nated as lakes “C,” “N,” and “O.” A limited survey of these lakes was made in connection with the preparation of this report. A general recession of the lake by evaporation has naturally re- sulted in an increased salinity which, although varying considerably with the seasons and localities, amounts to approximately 1% at the present time. The solids are, for the most part, sulphates of sodium and magnesium and sodium chloride. The following table represents the relative amounts of salts as determined by the United States Bureau of Chemistry from samples of water taken in June, 1906:^ Parts per Million Calcium bicarbonate 119.8 M agnesium bicarbonate 647 . 6 M agnesiu m carbonate 167.0 Magnesium sulphate 1,470.0 Sodium sulphate 4,758.9 Sodium chloride 1,354.0 Total 8,517.3 * Pope, T. E. B. Devil’s Lake, North Dakota, a study of physical and biological conditions, with a view to the acclimatization of fish. Bureau of Fisheries Document 634, 1908. PROTOZOA or THE DEVIL’S LAKE COMPLEX 169 The following analysis was made by the United States Bureau of Chemistry in 1907, from samples taken at Station 6, East Lake:^ Parts per Million Carbonic acid ion 154.9 Bicarbonic acid ion 555 . 6 Silica 44.0 Chlorin 1,122.0 Iron 16.4 Calcium 31.2 Magnesium 601 . 6 Sulphuric acid ion 6,254.4 Sodium 2,725.3 Potassium 250 . 0 The concentration of the water from East Lake was somewhat higher than that from any one of five other localities, the analyses of which were made at the same time. In the shallower parts and about the borders of the lake the ditch grass, Ruppia maritima^ forms luxuriant growths, while the greater portion of the bottom is covered with a thick layer of ooze. In 1901 Dr. Heath,^ then of the Department of Chemistry of the University of North Dakota, made the following analysis of the ooze from the bottom of Creel Bay, an arm of the main lake: Volatile (mostly organic matter) 28 . 80% SiOs 27.43% Insoluble sulphates 12 . 78% FejOa and AI 2 O 3 13.11% Calcium 8.97% Magnesium 0.47% Manganese 0 . 026% Moore (’17),® in concluding a list of algae from Devil’s Lake, says: “Excluding the diatoms, of which there seems to be a considerable number of species, the algal flora of Devil’s Lake can hardly be said to be recorded as a rich one.” This investigator attributes the almost total absence of certain groups of algae to the high content of salts in the water, but, in general, he finds the algal flora typically a fresh water one and showing little or no effect of the concentration of water. ® From unpublished notes. ® Moore, G. T. Preliminary list of algae in Devil’s Lake, North Dakota. Annals of the Missouri Botanical Garden 4; 293-303, November, 1917. 170 CHARLES HOWARD EDMONDSON, PH.D. Biological studies of Devil’s Lake made by the United States Bureau of Fisheries in 1908 indicate the presence of four vertebrate inhabitants of the lake, namely: a stickleback, Eucalia inconstans; a minnow, Pimephales promelas; the hellbender, Crytobranchus alleghaniensis ; and the leopard frog, Rana pipens. Among the metazoan invertebrates reported are crustaceans, rotifers, nematodes, a flat worm, an arachnid and a number of species of insects. One may collect the shells of at least fifteen molluscs from the water line on the shore, but no living forms have been taken from the lake. Sponges, coelenterates, polyzoans and annelids are apparently en- tirely absent. Investigations of the protozoan fauna of the Devil’s Lake complex were undertaken as a part of the general biological survey of that water area. Although, in many respects, this fauna was found to be such as one might expect in a fresh water lake of similar depth, yet some very pronounced differences were disclosed. The almost total absence of shell-bearing rhizopods may possibly find its explanation in the chemical analysis of the water. Arcella vulgaris Ehrenberg, a very constant and usually abundant form in fresh water, was rarely observed and two species of Dijiugia, which are among the most com- mon protozoa in lakes where there is considerable ooze, were taken only in situations where the salinity of the water must have been materially reduced by the in-seepage of surface water. A species of Euglypha was taken in the overflow of the lake water from the fish tank. The only other shelled rhizopod observed was a single speci- men of Cyhoderia ampulla Leidy, taken from the main lake. The fact that the ooze at the bottom of the lake at times has been found to be entirely free from oxygen might also be a contributing fac- tor to the scarcity of these usually common bottom-dwelling rhizopods of the shell-bearing type, although the presence of the larvae of a cer- tain midge in this ooze as well as the work of Birge and Juday in Wisconsin,^ where a considerable number of animals were found at the bottom of lakes in the absence of oxygen, would hardly seem to make this factor one of great importance. Experiments of a preliminary character, recorded at the end of the taxonomic part of this report, indicate that certain protozoa having ’ Birge and Juday, The Inland Waters of Wisconsin; Wisconsin Geological and Natural History Survey, 1911. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 171 adjusted themselves to fresh water conditions are not, in all cases at least, readily adaptable to the waters of Devil’s Lake. The writer wishes to acknowledge his indebtedness to Dr. R. T. Young, Director of the State Biological Station of North Dakota, whose co-operation made this report possible, and to Mr. E. G. Moberg for his valuable assistance in collecting material. 2. Taxonomy SUBPHYLUM SARCODINA CLASS RHIZOPODA SUBCLASS AMOEBAE ORDER GYMMAMOEBIDA Family Amoebic ae Genus Amoeba Ehrenberg, 1831 Amoeba proteus (Rbsel). Der kleine Proteus Rosel, Insecten Belustigung, 1755, tab. 101. Amoeba proteus Leidy, Pr. Ac. Nat. Sc., 1878. Occurrence. — Associated with Ruppia in Whipple Bay, Creel Bay, Minnewaukon Bay, Six-mile Bay, East Lake, and also taken from the east side of the main lake and from the overflow of lake water from the fish tank near the laboratory. Amoeba radiosa Ehrenberg. Amoeba radiosa Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — Rarely observed. Taken with Ruppia from Minne- waukon Bay, also from Big Mission Lake. Amoeba limax Dujardin. Amoeba limax Dujardin, Histoire Naturelle des Zoophytes In- fusoires, Paris, 1841. Occurrence. — Associated with Ruppia and algae at the head of Creel Bay, Big Mission Lake (numerous). Little Mission Lake (numerous), and the east side of the main lake (numerous). Amoeba verrucosa Ehrenberg. Amoeba verrucosa Ehrenberg, Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Observed but once, from material taken along the east side of Creel Bay. 172 CHARLES HOWARD EDMONDSON, PH.D. Amoeba guttula Dujardin, Amoeba guttula Dujardin, Histoire Naturelle des Zoophytes Infusoires, Paris, 1841. Occurrence. — Taken from algae near Brannon^s Island, from both ooze and floating algae in Creel Bay, from the east side of the main lake, and from sediment on rocks near, the Station. Amoeba striata P^nard. Amoeba striata Penard, fitudes sur les Rhizopodes d’eau douce. Mem. Soc. Phys. et Hist. Nat. Geneve, 1890. Occurrence. — One specimen only observed in plant infusion from Stump Lake. Amoeba vitraea (Hertwig and Lesser). Dactylosphaerium vitraem Hertwig and Lesser, Ueber Rhizopoden und denselben nahestehende Organismen. Arch. Mikr. Anat. Vol. 10, SuppL, 1874. Occurrence. — Taken from the east side of Creel Bay. ORDER TESTACEA Family Arcellidae Genus Difflugia Leclerc, 1815 Difflugia pyriformis Perty. Difflugia pyriformis Perty, Zur Kenntniss kleinster Lebensformen in der Schweiz, 1852. Occurrence. — Only observed from Big Mission Lake in a location where fresh water seeps into the lake. Difiiugia constricta Ehrenberg. Difflugia constricta Ehrenberg, Abh. Akad. Wiss. Berlin, 1841. Occurrence. — Taken from Big Mission Lake in the same situation as the preceding species, and also from the head of Creel Bay near the entrance of a sewer. Genus Arcclla Ehrenberg, 1830 Arcella vulgaris Ehrenberg. Arcella vulgaris Ehrenberg, Abh. Akad. Wiss. Berlin, 1830. Occurrence. — Taken in ooze from the head of Creel Bay and from near the station, also from Big Mission Lake near the in-seepage of fresh water; abundant in the latter locality. PROTOZOA OF THE DEVIL^S LAKE COMPLEX 173 Family Euglyphidae Genus Cyphoderia Schlumberger, 1845 C)^hoderia ampulla (Ehrenberg). Difflugia ampulla Ehrenberg, Bericht Preuss. Akad. Wiss., 1840. Occurrence. — One specimen only has been observed. Taken from Whipple Bay among Ruppia. Genus Euglypha Bujardin^ 1841 Euglypha alveolata Dujardin. Euglypha alveolata Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Taken from the overflow of lake water from the fish-tank near the Station. Observed but once. SUBCLASS HELIOZOA ORDER APHROTHORACIDA Genus Actinophrys Ehrenberg, 1830 Actinophrys sol Ehrenberg. Actinophrys sol Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — Rarely observed, taken from among Ruppia in Minnewaukon Bay. SUBPHYLUM MASTIGOPHORA CLASS ZOOMASTIGOPHORA SUBCLASS LISSOFLAGELLATA ORDER MONADIDA Family Rhizomastigidae Genus Cercomonas Dujardin, 1841 Cercomonas sp. Figures 1-3, Plate XVIII. Probably Cercomonas longicauda Dujardin. Very plastic with caudal filament often developed. Diameter, when spherical, 10^ Occurrence. — Observed in infusions from Stump Lake only. Family Heteromonadidae Genus Monas Muller, 1786 Monas sp. Figures 4, 5, Plate XVIII. Very plastic. Diameter, when spherical, 20/ii. May represent Monas fluida Dujardin. Occurrence. — In the ooze from Creel Bay. 174 CHARLES HOWARD EDMONDSON, PH.D. Monas sp. Figure 8, Plate XVIII. Length 9ju; body persistent in form, anterior region very granular. Corresponds in some degree to Monas irregularis Perty. Occurrence. — In the ooze from Creel Bay. From a stale culture of Ruppia, Creel Bay. Monas sp. Figure 7, Plate XVIII. Body moderately plastic. Length, when extended, 15-18/u. Possibly same as figures 4 and 5. Occurrence. — In the ooze from Creel Bay. ORDER HETEROMASTIGIDA Family Heteromitidae Genus Heteromita Dujardin, 1841 Heteromita globosa (Stein). Bodo glohosus Stein, Der Organismus des Infusionthiere, Abth. 3, 1878. Occurrence. — In dredged material from Creel Bay. Heteromita sp. Figure 6, Plate XVIII. But little of detail determined. Length 5/x. The form probably represents Heteromita ovata Du jar din. Occurrence. — Taken from ooze on rocks near the Station. ORDER POLYMASTIGIDA Family Polymastigidae Genus Trepomonas Dujardin, 1841 Trepomonas agilis Dujardin. Trepomonas agilis Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Taken from Big Mission Lake, Whipple Bay, from the ooze of the main lake and from the east side of the main lake. Abundant in the latter locality. ORDER EUGLENIDA Family Euglenidae Genus Euglena Ehrenbergy 1830 Euglena viridis Ehrenberg. Euglena viridis Ehrenberg Abh. Akad. Wiss., Berlin, 1830. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 175 Occurrence. — Observed from Minnewaukon Bay, Big Mission Lake, in the ooze from Creel Bay and from the east side of the main lake. Euglena desus Ehrenberg. Euglena desus Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — Minnewaukon Bay, Six-mile Bay, near Brannon^s Island, Big Mission Lake, Little Mission Lake, East Lake, and the ooze from the main lake. Genus Phacus Dujardin, 1841 Phacus pyrum (Ehrenberg). Euglena pyrum Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — Minnewaukon Bay, Creel Bay, Big Mission Lake (numerous), and the east side of the main lake. Genus Eutreptia Perty, 1852 Eutreptia viridis Perty. Eutreptia viridis Perty, Zur Kenntniss kleinster Lebensformen in der Schweiz, 1852. Occurrence. — From the surface among Ruppia^ Big Mission Lake. Family Astasiidae Genus Astasia Ehrenberg^ 1830 Astasia tricophora (Ehrenberg). Trachelius tricophorus Ehrenberg, Abh. Akad. Wiss., Berlin, 1830* Occurrence. — Among Ruppia from Whipple Bay, from Creel Bay, in the ooze from Big Mission Lake, and among algae near Brannon’s Island. Family Peranemiidae Genus Petalomonas Stein, 1859 Petalomonas mediocanellata Stein. Petalomonas mediocanellata Stein, Der Organismus der Infusions- thiere, 1878. Occurrence. — Taken from the surface of Big Mission Lake and from the ooze of the main lake. 176 CHARLES HOWARD EDMONDSON, PH.D. Petalomonas sp. Figure 10, Plate XVIII. Has some resemblance to Petalomonas ervilia Stein. Conspicuous groove entire length of the body. Length 36/i. Occurrence. — From the ooze of Creel Bay. Genus Heteronema Dujardin, 1841 Heteronema acus (Ehrenberg). Astasia acus Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — From Six-mile Bay and from the ooze of Creel Bay. Genus Anisonema Dujardin^ 1841 Anisonema grande (acinus) (Ehrenberg). Bodo grandis Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Anisonema acinus Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Among Ruppia and algae at the head of Creel Bay. Genus Notosolenus Stokes, 1884 Notosolenus sp. Figure 9, Plate XVIII. Length about IS/i. Occurrence. — From Whipple Bay, Stump Lake and from the overflow of the fish-tank near the Station. ORDER CHLOROFLAGELLIDA Family Tetramitidae Genus Tetraselmis Stein, 1878 Tetraselmis cordiformis (Carter). Cryptoglena cordiformis Carter, Annals of Natural History 1858. Occurrence. — Taken from Stump Lake only. Family Polytomidae Genus Polytoma Ehrenberg, 1838 Polytoma uvella Ehrenberg. Polytoma uvella Ehrenberg Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Found at the head and along the east side of Creel Bay. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 177 Family Trimastigidae Undetermined genus Undetermined species. Figures 11, 12, Plate XVIII. Description. — Body elongate, somewhat compressed, slightly plastic, attenuated posteriorly; surface marked longitudinally by several conspicuous ridges ; flagella three in number arising from the anterior extremity, equal and equalling the body in length; nucleus and contractile vacuole unobserved. Length 20ju. Occurrence. — Numerous among Ruppia from Creel Bay. Family Chlamydomonadidae Genus Chlamydomonas Ehrenberg, 1833 Chlamydomonas pulvisculus Ehrenberg. Chlamydomonas pulvisculus Ehrenberg, Abh. Akad. Wiss,, Berlin, 1833. Occurrence. — Taken from the head of Creel Bay. SUBCLASS DINOFLAGELLTDA ORDER DINIFERIDA Family Peridiniidae Genus Glenodinium Ehrenberg, 1832 Glenodinium pulvisculus Ehrenberg. Glenodinium pulvisculus Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Occurrence. — Taken from the surface and from the ooze at the bottom of Creel Bay. SUBPHYLUM INFUSORIA CLASS CILIATA ORDER HOLOTRICHA Family Enchelinidae Genus Holophrya Ehrenberg, 1831 Holophrya ovum Ehrenberg. Holophrya ovum Ehrenberg, Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Among algae from Creel Bay. 178 CHARLES HOWARD EDMONDSON, PH.D. Holophrya sp. Figure 13, Plate XVIII. Resembling Holophrya ovum Ehrenberg but much smaller. Length 30-40)u. Occurrence. — In the ooze from Creel Bay. Genus Urotricha Claparede and Lachmann, 1858 Urotricha labiata, new species, Figure 14, Plate XVIII. Description. — Body ovate, about twice as long as broad, equally rounded at both extremities. Cilia covering the entire body, ar- ranged in longitudinal rows and vibrating independently. A very fine seta, nearly as long as the body, extending from the posterior extremity. Mouth anterior, subterminal, beneath a prominent, lobe-like lip. Nucleus central. Contractile vacuole posterior. Reproduction by transverse fission. Length of body about 30/z. Occurrence. — Taken from numerous localities in DeviPs Lake. Genus Frorodon Ehrenberg, 1833 Prorodon teres Ehrenberg. Frorodon teres Ehrenberg, Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Among Ruppia and algae of Big Mission Lake and the main lake. Prorodon edentatus Claparede and Lachmann. Prorodon edentatus Claparede and Lachmann, Etudes sur les Infusoires et les Rhizopodes, 1858. Occurrence. — Infusions of Ruppia from Big Mission Lake and Minnewaukon Bay. Prorodon griseus Claparede and Lachmann. Prorodon griseus Claparede and Lachmann, Etudes sur les Infu- soires et les Rhizopodes, 1858. Occurrence. — Taken from Stump Lake only. Genus Enchelys Ehrenberg, 1838 Enchelys sp. Figure 15, Plate XVIII. Length from 15-20/x. Occurrence. — Ooze from the main lake and from the overflow of lake water from the fish-tank. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 179 Genus Spathidium Dujardin, 1841 Spathidium spatula Dujardin. Spathidium spatula Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Among algae from the head of Creel Bay. Spathidium sp. Figure 16, Plate XVIII. A very long, narrow and flattened form. Length 120)u. Occurrence. — Taken from infusions from the head of Creel Bay. Spathidium sp. Figure 17, Plate XVIII. A much shorter form than the preceding, with a conspicuous collar about the oral extremity. Length 30At. Occurrence. — From the ooze of the main lake. Undetermined Genus^ Undetermined species. Figures 1, 2, Plate XIX. Description. — Body elongate, plastic, slightly compressed dorso- ventrally, inflated posteriorly, narrow anteriorly, rounded at both extremities; cilia of uniform length arranged in longitudinal rows, covering the entire surface ; aperture a narrow slit diagonally placed, sub-terminal; contractile vacuole posterior; nucleus concealed; endo- plasm completely filled with green chloroplasts. Length 90/i. Occurrence. — From the surface of the main lake and from among Ruppia and algae. Genus Chaenia Dujardin, 1841 Chaenia teres Dujardin. Chaenia teres Dujardin, Histoire Naturelle des Zoophytes Infu- soires. 1841. Occurrence. — Among algae from the head of Creel Bay. Genus Mesodinium Stein, 1862 Mesodinium pulex (Claparede and Lachmann). Halteria pulex Claparede and Lachmann, Etudes sur les Infu- soires et les Rhizopodes, 1858. Occurrence. — A common form on the surface and in the ooze of the main lake. * The form is treated here with doubt as to its taxonomic position. 180 CHARLES HOWARD EDMONDSON, PH.D. Genus Didinium Stein, 1859 Didinium nasutum (Muller). Vorticella nasutum Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Occurrence. — Among Ruppia from Minnewaukon Bay, Whipple Bay, and from the east side of the main lake. Genus Lacrymaria Ehrenherg, 1830 Lacrymaria olor Ehrenberg. Lacrymaria olor Ehrenberg, Abh. Akad. Wiss., Berlin, 1830. Occurrence. — Among Ruppia in Creel Bay. Lacrymaria truncata Stokes. Lacrymaria truncata Stokes, Ann. and Mag. Nat. Hist., June, 1885. Occurrence. — Among Ruppia from the north end of the main lake. Lacrymaria cohnii Kent. Lacrymaria cohnii Kent, A Manual of the Infusoria, 1881-1882. Occurrence. — In an infusion from Stump Lake. Lacrymaria lagenula Claparede and Lachmann. Lacrymaria lagenula Claparede and Lachmann, fitudes sur les Infusoires et les Rhizopodes, 1858. Occurrence. — In ooze from the main lake. Family Trachelinidae Genus Lionotus Wrzcsniowski, 1870 Lionotus fasciola (Ehrenberg). Amphileptus fasciola Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Occurrence. — Abundant in many parts of the main lake, also taken from Stump Lake and Big Mission Lake. Lionotus sp. Figure 3, Plate XIX. A very small species. Length about 40/x. Often seen in conjuga- tion. Occurrence. — Among algae from Creel Bay. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 181 Genus Amphileptus Ehrenherg, 1830 Amphileptus meleagris (Ehrenberg). Trachelius meleagris Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Amphileptus meleagris Claparede and Lachmann, fitudes sur les Infusoires et les Rhizopodes, 1858. Occurrence. — Taken in Stump Lake and from algae at the head of Creel Bay. Family Chlamydodontidae Genus Nassula Ehrenberg, 1838 Nassula rubens (Perty). Cyclogramma ruhens Perty, Zur Kenntniss kleinster Lebensformen in der Schweiz, 1852. Nassula ruhens Claparede and Lachmann, fitudes sur les Infu- soires et les Rhizopodes, 1858. Occurrence. — From the overflow of lake water from the fish-tank near the Station. Nasula ornata Ehrenberg. Nasula ornata Ehrenberg, Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Taken from Lake “N” only. Genus Chilodon Ehrenberg, 1833 Chilodon cucullulus (Muller). Colpoda cucullulus Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Occurrence. — Infusions of algae from Creel Bay, Big Mission Lake, and Whipple Bay. Chilodon caudatus Stokes. Chilodon caudatus Stokes, Am. Jour. Sci. 29, April, 1885. Occurrence. — Among Ruppia from Minnewaukon Bay. Genus Aegyria Claparede and Lachmann, 1858 Aegyria, pusilla (?) Claparede and Lachmann. Aegyria pusilla Claparede and Lachmann, Etudes sur les Infu- soires et les Rhizopodes, 1858. Occurrence. — Among algae near the Station. 182 CHARLES HOWARD EDMONDSON, PH.D. Family Chileferidae Genus Glaucoma Ehrenberg, 1830 Glaucoma scintillans Ehrenberg. Glaucoma scintillans Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Occurrence. — In algae infusion from near Brannon’s Island. Glaucoma margaritaceum (Ehrenberg). Cyclidium margaritaceum Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Cinetochilum margaritaceum Perty, Zur Kenntniss kleinster Lebensformen in der Schweiz, 1852. Occurrence. — Very abundant. From the ooze of Creel Bay, the surface of Creel Bay, Stump Lake, and near Brannon’s Island in the main lake. Genus Leucophrys Ehrenberg, 1830 Leucophrys patula (Muller). Trichoda patula Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Occurrence. — One specimen only observed, from the east side of the main lake. A very typical specimen. Genus Frontonia Ehrenberg, 1838 Frontonia leucas Ehrenberg. Frontonia leucas Ehrenberg, Die Infusionsthierchen als Volkom- mene Organismen, 1838. Occurrence. — Taken from the east side of the main lake and from East Lake. Abundant in Six-mile Bay and Minnewaukon Bay. Genus Loxocephalus Eberhard, 1868 Loxocephalus granulosus Kent. Loxocephalus granulosus Kent, A Manual of the Infusoria, 1881- 1882. Occurrence. — Taken only in the ooze of Big Mission Lake near the in-seepage of fresh water. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 183 Genus Uronema Dujardin, 1841 Uronema marinum Dujardin. Uronema marinum Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — One of the most common species in the lake. Abundant everywhere both at the surface and in the ooze. Genus Colpidium Stein, 1868 Colpidium putrinum Stokes. Colpidium putrinum Stokes, Ann. and Mag. Nat. Hist. Feb., 1886. Occurrence. — From algae at the east side of Creel Bay. Genus Tillina Gruber, 1879 Tillina saprophila Stokes. Tillina saprophila Stokes, Am. Nat., Feb., 1884. Occurrence. — Taken only in the overflow of lake water from the fish-tank near the station. Family Paramaecidae Genus Paramaecium Muller, 1786 Paramaecium trichium Stokes. Paramaecium trichium Stokes, Am. Naturalist, 19, May, 1885. Occurrence. — From near the mouth of a sewer at the head of Creel Bay, and from ooze near the rock pile in the main lake. Paramaecium caudatum Ehrenberg. Paramaecium caudatum Ehrenberg. Die Infusionsthierchen als Volkommene Organismen, 1838. Occurrence. — Taken from Big Mission Lake near the in-seepage of fresh water. Family PLEURONEMmAL: Genus Cyclidium Ehrenberg, 1838 Cyclidium glaucoma Ehrenberg. Cyclidium glaucoma Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Occurrence. — Abundant everywhere, at the surface and in the ooze in all parts of the lake. 184 CHARLES HOWARD EDMONDSON, PH.D. Cyclidium litomesum Stokes. Cyclidium litomesum Stokes, Am. Monthly Micro. Jour., 6, Dec. 1884. Occurrence. — Numerous in infusions from the head of Creel Bay and in the ooze from the main lake. Genus Pleuronema Dujardin, 1841 Pleuronema chrysalis (Ehrenberg). Paramaecium chrysalis Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Pleuronema crassa Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Observed in infusions from Stump Lake only. ORDER HETEROTRICHA Family Plagiotomiidap: Genus Metopus ClaparHe and Lachmann, 1858 Metopus sigmoides (Muller). Trichoda sigmoides Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Occurrence. — Common in dredged material from Minnewaukon Bay, Creel Bay, and the main lake. Abundant in East Lake. Genus Spirostomum Ehrenberg, 1835 Spirostomum ambiguum Ehrenberg. Spirostomum ambiguum Ehrenberg, Abh. Akad. Wiss., Berlin, 1835. Occurrence. — Observed in dredged material from Creel Bay. Family Halteridae Genus Halteria Dujardin, 1841 Halteria grandinella (Muller). Trichoda grandinella Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Halteria grandinella Dujardin, Histoire Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Common in infusions of Ruppia and algae from Whipple Bay and Creel Bay and in the ooze of the main lake. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 185 ORDER HYPOTRICHA Family Oxytrichidae Genus Urohptus^ Ehrenberg, 183! Uroleptus agilis Englemann. Uroleptus agilis Englemann, Zeit. Wiss. Zool., Bd. 11, 1861. Occurrence. — From the ooze of the main lake, also from Six-mile Bay. Uroleptus rattulus (?) Stein. Uroleptus rattulus Stein, Der Organismus der Infusionsthiere, 1859. Occurrence. — Among Ruppia from Whipple Bay. Genus Oxytricho3 Ekrenberg, 1830 Oxytricha fallax Stein. Oxytricha fallax Stein, Der Organismus der Infusionsthiere, 1859. Occurrence. — Among algae from Creel Bay. Oxytricha pellionella (Muller). Trichoda pellionella Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Oxytricha pellionella Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Occurrence. — Taken from Ruppia near the Station, Big Mission Lake, Whipple Bay, north end of Creel Bay, and the ooze from the fish-tank after being flooded by lake water. Oxytricha parvistyla Stein. Oxytricha parvistyla Stein, Der Organismus der Infusionsthiere, 1859. Occurrence. — Among Ruppia near the Station. Oxytricha bifaria Stokes. Oxytricha hifaria Stokes, Ann. and Mag. Nat. Hist., Aug., 1887. Occurrence. — Abundant in Creel Bay, also taken from Whipple Bay. * Further study would, no doubt, result in the determination of other species of the genus than those listed. 186 CHARLES HOWARD EDMONDSON, PH.D. Genus Ilistrio Sterki, 1878 Histrio erethysticus Stokes. Histrio erethysticus Stokes, Proc. Am. Philos. Soc. 24; 126, 1887 Occurrence. — Among Ruppia from near the Station. Genus Stylonychia Ehrenherg, 1830 Stylonychia notophora Stokes. Stylonychia notophora Stokes, Ann. and Mag. Nat. Hist. June, 1885. Occurrence. — With algae from Creel Bay. Genus Holosticha Wrzesniowski, 1877 Holosticha vernalis (?) Stokes. Holosticha vernalis Stokes, Ann. and Mag. Nat. Hist., Aug., 1887. A form bearing considerable resemblance to Stokes^ species was occasionally observed. Length 140/i. Occurrence. — Among Ruppia from the main lake. Genus Fleurotricha Slein, 1859 Pleurotricha lanceolata (Ehrenberg). Stylonychia lanceolata Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Pleurotricha lanceolata Stein, Der Organismus der Infusionsthiere, 1859. Occurrence. — Taken at the head of Creel Bay. Genus Tachysoma Stokes, 1887 Tachysoma parvistyla Stokes. Tachysoma parvistyla Stokes, Ann. and Mag. Nat. Hist. Aug., 1887. Occurrence. — Observed in infusions from Stump Lake only. Family PZuplotidae Genus Euploles Ehrenberg, 1831 Euplotes charon (Muller). Trichoda charon Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Euplotes charon Ehrenberg, Die Infusionsthiere als Volkom- mene Organismen, 1838. PROTOZOA OF THE DEVIL S LAKE COMPLEX 187 Occurrence. — Abundant among infusions of Ruppia and algae from many parts of the main lake, and also from East Lake. Euplotes patella (Muller), Kerona patella Muller, Animalcula Infusoria Fluviatilia et Marina, 1786. Euplotes patella Ehrenberg, Die Infusionsthiere als Volkommene Organismen, 1838. Occurrence. — Found in Stump Lake, Big Mission Lake, East Lake and in numerous localities in the main lake. Genus Aspidisca Ehrenberg, 1830 Aspidisca costata (Dujardin). Coccudina costata Dujardin, His tore Naturelle des Zoophytes Infusoires, 1841. Occurrence. — Taken in Whipple Bay; numerous among Ruppia in Minnewaukon Bay and also on the east side of the main lake. ORDER PERITRICHA Family Vorticellidae Genus Vorticella Linnaeus, 1767 Vorticella telescopica Kent. Vorticella telescopica Kent, a Manual of the Infusoria, 1881-1882. Occurrence. — Among Ruppia at the north end of the main lake. Vorticella convallaria Linnaeus. Vorticella convallaria Linnaeus, Systema Naturae, Ed. 12, 1767. Occurrence. — Attached to diatoms in the main lake, also among Ruppia in Big Mission Lake. Vorticella octavo Stokes. Vorticella octavo Stokes, Ann. and Mag. Nat. Hist., June, 1885. Occurrence. — Among Ruppia at the north end of the main lake. Vorticella microstoma Ehrenberg. Vorticella microstoma Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Occurrence. — Taken at the east side of the main lake. 188 CHARLES HOWARD EDMONDSON, PH.D. Vorticella sp. Figure 4, Plate XIX. A very common form, resembling Vorticella rabdostyloideslL^Micott but is considerably smaller and the body is transversely striated. Length of stalk 12ju, with the diameter of the body nearly the same. Occurrence. — Attached to floating diatoms. Vorticella sp. Figure 5, Plate XIX. A species with more elongate body than the preceding but also transversely striate. Length of body 28/z, stalk 68)u. Occurrence. — Attached to floating diatoms. Genus Gerda Claparede and Lachmann, 1858 Gerda annulata, new species. Figure 10, Plate XIX. Description. — Body elongated, cylindrical, of nearly equal diameter throughout, curved when extended; surface finely striate transversely; a prominent annular ridge present usually about one- fourth the distance from the posterior extremity; peristome border revolute, disc slightly elevated; contractile vacuole conspicuous; nucleus not observed. Length of body, extended, 80/i. Occurrence. — Among algae and Ruppia from the north end of the main lake. Genus Epistylis Ehrenberg, 1830 Epistylis plicatilis Ehrenberg. Epistylis plicatilis Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Occurrence. — From the east side of Creel Bay. Epistylis branchiophila Perty. Epistylis branchiophila Perty, Zur Kenntniss kleinster Lebensfor- men in der Schweiz, 1852. Occurrence. — Among algae near the head of Creel Bay. Genus Carchesium Ehrenberg, 1838 Carchesium epistylidis Claparede and Lachmann. Carchesium epistylidis Claparede and Lachmann, Etudes sur les Infusoires et les Rhizopodes, 1858. Occurrence. — Among algae from Creel Bay. PROTOZOA OF THE DEVIL^S LAKE COMPLEX 189 Genus Zoothawnium Ehrenberg, 1838 Zoothamnium alterans Claparede and Lachmann. Zoothamnium alterans Claparede and Lachmann, Etudes sur les Infusoires et les Rhizopodes, 1858. Occurrence. — Among Ruppia and algae from Stump Lake. Zoothamnium sp. Figure 6, Plate XIX. Stalk very stout, zooids smooth, usually 2-8 in a colony. Length of stalk 216/i, of zooid 64/i. Occurrence. — From Stump Lake, East Lake, Creel Bay, Whipple Bay, and from the main lake. Attached to algae or Ruppia. A fairly common form. Genus V aginocola Lamarck, 1816 Vaginocola crystallina Ehrenberg. V aginocola crystallina Ehrenberg, Die Infusionsthierchen als Volkommene Organismen, 1838. Occurrence. — Numerous among algae from East Lake, also taken from Stump Lake and from the north end of the main lake. Genus Cothurnia Ehrenberg, 1831 Cothurnia imberbis Ehrenberg. Cothurnia imberbis Ehrenberg, Die Infusionsthierchen als Vol- kommene Organismen, 1838. Occurrence. — Commonly attached to floating diatoms, from dredged material and also among Ruppia in Creel Bay. Also taken from Stump Lake. Cothurnia curva Stein. Cothurnia curva Stein, Der Organismus der Infusionsthiere, 1859. Occurrence. — Among Ruppia at the north end of the main lake. CLASS SUCTORIA Family Podophryidae Genus Podophrya Ehrenberg, 1838 Podophrya libera Perty. Podophrya libera Perty, Zur Kenntniss kleinster Lebensformen in der Schweiz, 1852. Occurrence. — Numerous at east side of the main lake. 190 CHARLES HOWARD EDMONDSON, PH.D. Podophrya sp. Figure 9, Plate XIX. Bears some slight resemblance to Podophrya cyclopum Clapar^de and Lachmann. The lobulated border may have represented a reproductive phase or possibly was abnormal. Total height 60 m, stalk 20m* Occurrence. — Attached to algae from the main lake. Several specimens were observed by Dr. R. T. Young. Genus Sphaerophrya Claparede and Lachmann, 1858 Sphaerophrya magna Maupas. Sphaerophrya magna Maupas, Arch, de Zoologie Experimentale, tom 9, Nov., 1881. Occurrence. — From Stump Lake and the east side of the main lake. Family Acinetidae Genus Acineia Ehrenherg, 1838 Acineta sp. Figure 7, Plate XIX. Body triangular in broad view, compre sed; endoplasm very granular, nucleus concealed. Total height 50m, stalk 20m. This species resembles, in some degree, Acineta lemnarum Stein. Occurrence. — From floating material in the main lake and also among algae from Stump Lake. Acineta sp. Figure 8, Plate XIX. Body oval, slightly broader distally, greatly compressed; endo- plasm granular concealing the nucleus and contractile vacuole. Total height 60-72m, stalk about 15m. Occurrence. — Attached to algae from Stump Lake. Commonly feeding on Uronema. 3. Experiments Preliminary experiments in transferring protozoa from fresh water to the con- centrated water of Devil’s Lake and vice versa. In order to test the reactions of certain protozoa taken from other sources to the more concentrated waters of Devil’s Lake a series of simple experiments were carried out by which forms of protozoa common to fresh water were transferred directly into the more saline water of the lake. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 191 Infusions from a small body of fresh water near the southern boundary of the main lake were prepared and certain protozoa which readily appear in cultures were used in the tests. By placing a drop of the fresh water culture on one end of a micro- scopic slide and a drop of lake water near the middle of the slide and, with a needle, drawing out from each drop toward the other a narrow channel of water until the two met, the protozoa were conducted from the fresh water drop into that of the lake water. To eliminate possible influence of the fresh water a series of drops of lake water were used and the organisms rapidly transferred from one to the other until they reached a pure medium of lake water. The waters from the two sources were kept at a uniform tempera- ture and the effect of the change of environment thus brought about was carefully noted by the activity of the organisms. In similar manner the transference of certain protozoa from lake water to fresh water was accomplished and the effect of such change observed as hereinafter noted. A. Transference of protozoa from fresh water to lake water. 1. Paramaecium sp. A specimen of a species, probably P^zrawae- cium caudatum Ehrenberg, commonly occurring in the fresh water was removed to the pure lake water with the following results: An immediate change occurred in the organism. The body became greatly compressed dorso-centrally with erratic movements at first which soon gave way to a more steady, forward movement with slow rotations on the long axis. A noticeable change also occurred in the contractile vacuoles. The normal rhythmic collapse of the vacuoles ceased after a few minutes and they became greatly dilated and dis- torted. After ten minutes of rotary movements the organism became quiet with the cilia of the periphera and the oral groove still active. Many non-contractile vacuoles filled the endoplasm. Death occurred at the end of twelve minutes. A second specimen, after showing the same flattening of the body, moved in circles for six minutes then assumed the forward movement with rotations on the long axis. In eighteen minutes the organism became quiet with a highly vacuolated endoplasm and the cilia of the oral groove vibrating feebly. Death occurred in twenty-six minutes. 192 CHARLES HOWARD EDMONDSON, PH.D. A third specimen after exhibiting similar physical and physiologi- cal changes came to complete rest in twenty-two minutes. Death resulted in twenty-five minutes. A fourth specimen showed similar responses and died in fifteen minutes. Seven specimens were then transferred at the same time. Six of these, after exhibiting similar responses as the preceding, were dead at the end of ten minutes. One, after reacting in like manner, died at the end of eighteen minutes. 2. Stylonychia sp. Several tests with a species of Stylonychia were carried out. Unusual responses were less quickly manifested by Stylonychia than Paramaecium when brought into contact with the lake water. Commonly after five or six minutes of normal movements a rapid whirling over and over of the body occurred gradually sub- siding into complete rest. Death occurred in all specimens in from sixteen to thirty-two minutes. Reactions of similar character were obtained from Paramaecium and Stylonychia by the introduction of small quantities of NaCL into the fresh water in which they were normally living. 3. Metopus sp. A short type of Metopus^ common in fresh water, was transferred to the saline lake water. The most noticeable change was an almost immediate flattening of the body. Normal rotary movements continued for eight minutes when the organism came to rest with the cilia of the surface still more or less active. Death occurred at the end of fifteen minutes. Numerous individuals of this species were used in successive experiments with reactions similar in each case. Death resulted in all specimens in from eleven to eighteen minutes. B. Transference of protozoa from the concentrated lake water to fresh water. 1. Uroleptus sp. The form used was one of the elongated types. More than sixty specimens were used in the tests. With few excep- tions but with considerable degree of variation, the following reactions were very evident: After a period of from ten to fifteen minutes contact with the fresh water, during which time more or less normal activities were maintained, the organisms came to rest with the cilia still in motion. The cell bodies became shortened and dilated, in PROTOZOA OF THE DEVIL'S LAKE COMPLEX 193 many instances assuming a spherical form. After enduring this state of depression for from ten to fifteen minutes the organisms showed signs of recovery. The bodies gradually assumed an elongated form and normal activities reappeared. Within a period of one hour and twenty-five minutes from the time the organisms were first introduced into the fresh water all, with the exception of a few which failed to survive the state of depression, had fully recovered and were respond- ing in a normal manner. Considerable variation in the effect of the change was noted. Of those surviving some were slightly affected and wholly recovered in forty-five minutes, some in sixty minutes, while others required the longer time noted above. 2. Euplotes patella (Muller). Numerous individuals of this spe- cies were transferred as in the preceding experiment. The effect in this case was an immediate one. As soon as contact was made with the fresh water the cell bodies became swollen and distorted, losing the longitudinal striations and all resemblance to normal individuals. During this state of depression the organisms were at rest with the cirri in feeble motion. After a period of fifteen minutes the cells began to resume movements although in a distorted condition. In fifteen minutes more the longitudinal striations reappeared and soon after normal responses were entirely restored. 3. Uronema marinum Dujardin. The transferrence of this spe- cies from the lake water to fresh water resulted in no apparent state of physical depression and no diminished or unusual responses to stimuli could be detected. The species is commonly recognized as both a marine and fresh water form. 4. Summary and Conclusions Summary of the Groups of Protozoa Recorded Sarcodina 13 species Mastigophora 22 ” Infusoria 76 ” Total Ill species Conclusions 1. The proportion of the number of species of the three groups of protozoa recognized in Devil’s Lake corresponds favorably with the same in a typical fresh water lake. 194 CHARLES HOWARD EDMONDSON, PH.D. 2. A most noticeable feature of the study of this fauna is the apparent total absence of numerous forms universally found in fresh water. The dearth of shell-bearing rhizopods was mentioned in the introduction. Many common species of flagellates and ciliates were, at no time during the survey, observed in the concentrated waters of the lake. 3. The subdivisions of the classes of protozoa are fairly well represented in DeviFs Lake. Two new species are described in the report but with the exception of the facts mentioned in the preceding paragraph, the protozoan fauna of Devil’s Lake cannot be considered an unusual one. 4. Experiments of the interchange of protozoa between fresh water and the lake water seem to indicate that the organisms of the lake may adjust themselves to fresh water conditions with more readiness than can the forms accustomed to a fresh water environ- ment accommodate themselves to the concentrated water of the lake. PROTOZOA OF THE DEVIL’S LAKE COMPLEX 195 5. Index Page Acineta 190 Acinefa lefnnarum 190 Acineta sp 190 Acinetidae 190 Actinophrys 173 Actinophrys sol 173 Aegyria 181 Aegyria pusiUa 181 Amoeba 171 Amoebae 171 Amoeba guttula 172 Amoeba limax 171 Amoeba proteus 171 Amoeba radiosa 171 Amoeba striata 172 Amoeba verrucosa 171 Amoeba vitraea 172 Amoebidae 171 Amphileptus 181 Amphileptus fasciola 180 Amphileptus meleagris 181 Anisonema 176 A nisonema acinus 176 Anisonema grande 176 Aphrothoracida 173 ArceUa 172 Arcella vulgaris 172 Arcellidae 172 Aspidisca 187 Aspidisca costata 187 Astasia 175 Astasia acus 176 Astasia tricophora 175 Astasiidae 175 Bodo glohosus 174 Bodo grandis 176 Carchesium 188 Carchesium epistylidis 188 Cercomonas 173 Cercomonas longicauda 173 Cercomonas sp 173 Page Chaenia 179 Chaenia teres 179 Chiliferidae 182 Chilodon 181 Chilodon caudatus 181 Chilodon cucullulus 181 Chlamydodontidae 181 Chlamydomonadidae 177 Chlamydomonas 177 Chlamydomonas pulvisculus 177 Chloroflagellida 176 Cilia ta 177 Cinetochilum margaritaceum 182 Coccudina costata 187 Colpidium 183 Colpidium putrinum 183 Colpoda cucullulus 181 Cothurnia 189 Cothurnia curva 189 Cothurnia imberbis 189 Cryptobranchus alleghaniensis 170 Cryptoglena cordiformis 176 Cyclidium 183 Cyclidium glaucoma 183 Cyclidium litomesum 184 Cyclidium margaritaceum 182 Cyclo gramma rubens 181 Cyphoderia 173 Cyphoderia ampulla 173 Dactylosphaerium vitraem 172 Didinium 180 Didinium nasutum 180 Difflugia 172 Diffiugia ampulla 173 Difflugia constricta 172 Difflugia pyrif ormis 172 Diniferida 177 Dinoflagellida 177 Enchelinidae 177 Enchelys 178 Enchelys sp 178 196 CHARLES HOWARD EDMONDSON, PH.D. Epistylis Epistylis branchiophila . . . Epistylis plicatilis Eucalia inconstans Euglena Euglena deses Euglena pyrum Euglena viridis Euglenida Euglenidae Euglypha Euglypha alveolata Euglyphidae Euplotes Euplotes charon Euplotes patella Euplotidae Eutreptia Eutreptia viridis Frontonia Frontonia leucas Glaucoma Glaucoma margaritaceum Glaucoma scintillans Glenodinium Glenodinium pulvisculus . Gerda. . Gerda annulata Gymnamoebida Halteria Halteria grandinella Halteria pulex Halteridae Heliozoa Heteromastigida Heteromita Heteromita globosa Heteromita ovata Heteromita sp Heteromitidae Heteromonadidae Heteronema Page Heteronema acus 176 Heterotricha 184 Histrio 186 Histrio erethysticus 186 Holophrya 177 Holophrya ovum 177 Holophrya sp 178 Holosticha 186 Holosticha vernalis 186 Holotricha 177 Hopotricha 185 Infusoria 177 Kerona patella 187 Lacrymaria 180 Lacrymaria cohnii 180 Lacrymaria lagenula 180 Lacrymaria olor 180 Lacrymaria truncata 180 Leucophrys 182 Leucophrys patula 182 Lionotus 180 Lionotus fasciola 180 Lionotus sp 180 Lisso^agellata 173 Loxocephalus 182 Loxocephalus granulosus 182 Mastigophora 173 Mesodinium 179 Mesodinium pulex 179 Metopus 184 Metopus sigmoides 184 Metopus gp 192 Monadida 173 Monas 173 Monas fluida 173 Monas irregularis 174 Monas sp 174 Nassula 181 Nassula ornata 181 Nassula rubens 181 Page 188 188 188 170 174 175 175 174 174 174 173 173 173 186 186 187 186 175 175 182 182 182 182 182 177 177 188 188 171 184 184 179 184 173 174 174 174 174 174 174 173 176 PROTOZOA OF THE DEVIL’S LAKE COMPLEX 197 Notosolenus Notosolenus sp Oxytricha Oxytricha bifaria Oxytricha fallax Oxy tricha parvistyla Oxytricha pellionella Oxytrichidae Paramaecidae Paramaecium Paramaecium caudatum .... Paramaecium chrysalis Paramaecium sp Paramaecium trichium Peranemiidae . . Peridiniidae Peritricha Petalomonas Petalomonas ervilia Petalomonas mediocanellata Petalomonas sp Phacus Phacus pyrum Pimephales promelas Plagiotomiidae Pleuronema Pleuronema chrysalis Pleuronema crassa Pleuronemidae Pleurotricha Pleurotricha lanceolata Podophrya Podophrya cyclopum Podophrya libera Podophrya sp Podophryidae Polymastigida Polymastigidae Poly toma Polytoma uvella Polytomidae Prorodon Prorodon edentatus Page Prorodon griseus 178 Prorodon teres 178 Rana pipens 170 Rhizomastigidae 173 Rhizopoda 171 Sarcodina 171 Spathidium 179 Spathidium spatula 179 Spathidium sp 179 Sphaerophrya 190 Sphaerophrya magna 190 Spirostomum 184 Spirostomum ambiguum 184 Stylonychia 186 Stylonychia lanceolata 186 Stylonychia notophora 186 Stylonychia sp 192 Suctoria 189 Tachysoma 186 Tachysoma parvistyla 186 Testacea 172 Tetramitidae 176 Tetraselmis 176 Tetraselmis cordiformis 176 Tillina 183 Tillina saprophila 183 Trachelinidae 180 Trachelius meleagris 181 Trachelius iricophorus 175 Trepomonas 174 Trepomonas agilis 174 Trichoda charon 186 Trichoda grandinella 184 Trichoda palula 182 Trichoda pellionella 185 T richoda sigmoides 184 T r imastigidae 177 Undetermined genus 177,179 Undetermined species 177,179 Uroleptus 185 Uroleptus agilis 185 Page 176 176 185 185 185 185 185 185 183 183 183 184 191 183 175 177 187 175 176 175 176 175 175 170 184 184 184 184 183 186 186 189 190 189 190 189 174 174 176 176 176 178 178 198 CHARLES HOWARD EDMONDSON, PH.D. Page Page Uroleptus rattulus 185 Vorticella nasutum 180 Uroleptus sp 192 Vorticella octavo 187 Uronema 183 Vorticella rabdostyloides 188 Uronema marinum 183 Vorticella sp 188 Urotricha 178 Vorticella telescopica 187 Urotricha labiata 178 Vorticellidae 187 Vaginocola 189 Zoomastigophora 173 Vaginocola crystallina 189 Zoothamnium 189 Vorticella 187 Zoothamnium alterans 189 Vorticella convallaria 187 Zoothamnium sp 189 Vorticella microstoma 187 EXPLANATION OF PLATES Plate XVIII Figs. 1-3. Cercomonas sp. x 1000. Figs. 4, 5. Monas sp. x 750. Fig. 6. Heteromita sp. x 2000. Fig. 7. Monas sp. x 1200. Fig. 8. Monas sp. x 1500. Fig. 9. Notosolenus sp. x 900. Fig. 10. Petalomonas sp. x 600. Figs. 11, 12. Undetermined genus and sp. x 1250. Fig. 13. Holophrya sp. x 550. Fig. 14. Uronema labiata, new sp. x 750. (Posterior seta omitted in figure.) Fig. 15. Enchelys sp. x 1200. Fig. 16. Spathidium sp. x 300. Fig. 17. Spathidium sp. x 900. Plate XIX Figs. 1, 2. Undetermined genus and sp. x 380. Fig. 3. Lionotus sp. x 800. Fig. 4. Vorticella sp., including stalk, x 800. Fig. 5. Vorticella sp., including stalk, x 350. Fig. 6. Zoothamnium sp., including stalk, x 250. Fig. 7. Acineta sp., including stalk, x 400. Fig. 8. Acineta sp., including stalk, x 280. Fig. 9. Podophrya sp., including stalk, x 370. Fig. 10. Gerda annulata, new species, x 500. 7'KAASACTJOXS OF THE AMERICAN MICROSCOPICAL SOCIETY VOL. XXXIX IM.ATK XVTTI KDMO.VDSOX TRAXSACnOXS OF THE AMERICAX M JC ROSCOPJCA !. SOCIETY VOL. XXXIX PLATE XIX i<:i)M()Xi)S()\ I