W. L. IB/oL/n 
 
 The, la.KOnom^ f{ n<i Morphology Of Some- HeW„- 
 
 r/i«s(oorwm« With Gemcolarhe. ■ 
 
 - 
 
 \ 
 
 * 
 
 < 
 
 \ 
 
THE TAXONOMY AND MORPHOLOGY OF SOME 
 HELMINTHOSPORIUMS WITH GEN- 
 ICULATE CONIDIA 
 
 BY 
 
 WALTER LEROY BLAIN 
 A. B. WABASH COLLEGE 
 1916 
 
 THESIS 
 
 Submitted in Partial Fulfillment of the Requirements for the 
 
 Degree of 
 
 MASTER OF ARTS 
 IN BOTANY 
 
 IN 
 
 THE GRADUATE SCHOOL 
 
 OF THE 
 
 UNIVERSITY OF ILLINOIS 
 
 1921 
 
Digitized by the Internet Archive 
 in 2015 
 
 https://archive.org/details/taxonomymorpholoOOblai 
 
UNIVERSITY OF ILLINOIS 
 
 THE GRADUATE SCHOOL 
 
 May 5 191??: 
 
 
 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY 
 
 SUPERVISION BY — Walter Leroy Blain 
 
 entttt f.d The Taxonomy and Mor p holog y of some Helmintho- 
 
 sp o riuma with Geniculate Conidla. 
 
 BE ACCEPTED AS FULFILLING THIS PART OF THE REQUIREMENTS FOR 
 THE DEGREE OF Ma,s-te- r o f A rt-s 
 
 In ^Charge of Thesis 
 
 Head of Department 
 
 Recommendation concurred in* 
 
 Committee 
 
 on 
 
 Final Examination* 
 
 *Required for doctor’s degree but not for master’s 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ) 
 
 
 
 
 
 
 
 
 
 
 
TABLE OF CONTENTS. 
 
 Page 
 
 I. Introduction — 1 
 
 II. Key to Genera Ordinarily Confused 
 
 with Helmintho sporium — 2 
 
 III. Accession List, — — — — 5 
 
 IV. Methods of Study — 6 
 
 V. Descriptions of Forms Studied — — — 8 
 
 VI. Variations -_12 
 
 VII. Conclusions — - — — — — 13 
 
 VIII. Literature Cited — — .. — — 
 

 
 
 
 
 
 
 
 
 
 . 
 . 
 
 ; I 
 
 
 
 
 
 
 
 
 
- 1 - 
 
 I. Introduction. 
 
 Those species of the genus Helminthosporiura character- 
 ized by conidia of from 3 to 5 cells differ in respect to the 
 shape of a centrally located cell. In some of these species the 
 cell referred to is equilateral; in others it is not equilateral 
 in that it is knee-form or geniculate. These conidia are further 
 characterized by the fact that the terminal cells are much lighte 
 in color than the intervening cells, 
 
 Glosexy allied to the species of Helminthosporium which 
 exhibit these conidial characters are species that are now regard- 
 ed, for one reason or another, as belonging to certain other 
 genera. This similarity in conidial structure suggests that they 
 are oogeneric with Helmihthosporium. In the genera Acrothecium 
 and Brachysporium, in particular, species with conidia of the 
 geniculate type have been described. Saccardo (1) lists 11 genera 
 namely, Acrothecium, Blastotrichum, Brachysporium, Cercospora, 
 Cladosporiura, Clasterosporium, Monotosporium, Mystrosporium , 
 Napicladium, Scolecotrichum, and Vermicularia, which he says are 
 frequently confused with Helminthosporium. 
 

 
 
 
 
 
 
 
 
 . 
 
 
 
 . 
 
 
 
 
 
 
 
 
 
 
 
 
 ' 
 
 
 . - 
 
 
 
-3- 
 
 II. Key to Genera 
 
 Ordinarily Confused with Helminthosporium. 
 
 The general conception of the relation of these genera 
 as described by Lindau (2) is shown in the following key: 
 
 1. Spores in pycnidia 
 
 Pycnidia appendaged or hairy, conidia cylindric, fusoid, 
 
 and irregular — • — - — Verraicularia 
 
 !• Spores on separate conidiophores 
 
 2, Conidiophores and conidia pale — — (Mucedinaceae) 
 
 Conidia 3 to several-celled, long — (Phragmosporae) 
 
 Fertile hyphae manifest and distinct from the 
 
 conidia, irregularly branched — - Blastotrichum 
 
 2. Conidiophores dark, conidia usually dark - (Dematiaceae) 
 
 3. Conidia one-celled, short — — - — - ( Amerosporae) 
 
 Conidiophores distinct from the mycelium, conidia 
 not in chains, borne terminally on simple free 
 
 conidiophores — ■ — — — — (Monotosporae) 
 
 Conidia dark ■ — — — — — — — — Monotospora 
 
 3. Conidia 2-celled — — — (Didymosporae) 
 
 Conidiophores distinctly different from the mycelium 
 Conidia not in chains, terminal or lateral, 
 conidiophores unbranched, short — — Scolecotrichum 
 Conidia in chains, conidiophores branched, 
 long - 
 
 Cladosporium 
 

 
 ‘ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 . . . 
 
 
 . 
 
 
 

 -3- 
 
 3. Conidia with three or more cells, long 
 
 (Phragmosporae) 
 
 Conidiophores very short or little different from 
 the conidia; conidia dark, ovoid to cylindric to 
 vermicular, separate, solitary — — — Clasterosporium 
 Conidiophores distinctly different from the 
 
 conidia — — - — Napicladium 
 
 4. Conidiophores stiff 
 
 5. Conidia terminal, solitary 
 
 6 . Smooth, long --- — Helminthosporium 
 
 6. Conidia shorter — — -- Brachysporium 
 4. Conidiophores lax 
 
 5. Conidia in terminal heads - Acrothecium 
 3. Conidia muriform, spindle-shaped, long -(Dictysporae) 
 Conidiophores stiff, distinctly different from the 
 
 conidia; conidia terminal, dark —————— Mystrosporium 
 
 3, Conidia thread-like or vermiform, with one or more 
 
 cells, dark or hyaline — (Scolecosporae) 
 
 . _ - — — — — - Cercospora 
 
 Though all these genera may in certain instances be 
 confounded with Helminthosporium, the Helminthosporiums with 
 geniculate conidia are readily distinguished, e. g. , from Vermi- 
 cularia by the absence of a pycnidium; from Mystrosporium by the 
 

 
 
 
 
 
 
 
 
 - 
 
 - 
 
 ■ 
 
 
 
 
 
 
 
 
 
 
 . 
 
 
 
-4- 
 
 ab 8 en ce of murifonn conidia; and from Cercospora by the absence 
 of vermiform or filiform conidia. The other genera listed by 
 Saccardo as being confused with Helminthosporium, differ very 
 little from each other with respect to these characters. In the 
 latter differentiation is based upon the number of cells in the 
 conidia and the length of conidiophores. Such characters are 
 variable and often lead to confusion. 
 
 That the present conceptions of generic limitations 
 do not agree, is brought out very forcefully by the incorrect 
 placing of at least 36 of the 334 species listed by Saccardo 
 as belonging to the genus Helminthosporium. For example, the 
 genus Helminthosporium is defined by Saccardo as follows: "Hyphae 
 rigidulae, subsimplices, fuscae, saepius epixylae. Conidia 
 fusoidea, vel elonga-to-ciavata, vel cylindracea, plurisepta, 
 fusca, rigida, levia." He lists one species with no septum, one 
 with 0 to 3, three with 1 to 3, eight with -1 to 3, three with 3, 
 eight with 3 to 3, and two with 1 to 4. 
 
 The geniculate type of conidium has been reported in 
 only three of the genera listed above, namely, Acrothecium, Brachy- 
 sponum, and Helminthosporium. As the present paper is concerned 
 with this peculiar conidial type, closer attention may therefore 
 be given to the differences upon which the separation of these 
 genera is based. Saccardo, Lindau (3) and Clements (3) state 
 that the three genera are very similar with respect to this 
 
■ 
 
 . 
 
 
 
 ■ 
 
 
 
 
 
 ■ 
 
 
 .. .. 
 
 
 
 

 character. Acrothecium is characterized by acrogenous conidia 
 forming a headj while Brachysporium and Helminthosporium are 
 characterized by having the conidia borne terminally and usually 
 singly. Helminthosporium is set apart from the former genus 
 through having longer conidia. 
 
 The purpose of the present paper is to make a compara- 
 tive study of all the available forms of these closely allied 
 genera possessing geniculate conidia. The following accession 
 list shows the forms under study, which will hereafter be referred 
 to by number, and indicates also their origin and the essential 
 points of their history. 
 
 III. Accession List. 
 
 The forms embraced in the present study are given in 
 the following accession list: 
 
 No. 35 was isolated from the Missouri black raspberry by Leva B. 
 Walker of the University of Nebraska, Lincoln, Nebraska, on July 
 4, 1919. 
 
 No. 37 was isolated from Sudan Grass (Andropogon sp.), grown in 
 a moist chamber by the writer on October 13, 1930. 
 
 No. 28 was isolated from Amber Cane (Andropogon sorghum) by F. L. 
 Stevens on December 7, 1930. 
 
 No. 29 was isolated from a broken corn stalk at Fort Branch, 
 Indiana, by G. N. Hoffer on August 13, 1919. 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 * 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
- 6 - 
 
 No. 30 was isolated from brown, water-soaked lesions on the 
 sheath of a corn leaf collected at Sullivan, Indiana, by G. N. 
 Hoffer on August 12, 1919. 
 
 No. 31 was isolated from small, brown, regular spots on corn 
 leaves from Delphi, Indiana, by G. N. Hoffer in August, 1919. 
 
 No. 32 was isolated from very small, yellow spots on corn leaves 
 from Battle Ground, Indiana, by G. N. Hoffer on August 7, 1919. 
 
 The writer has attempted to isolate a large number of 
 forms from as many diverse hosts as possible. The seven forms 
 described in this paper have all been isolated from some member 
 of the grass family (Gramineae) , with the exception of one found 
 on the Missouri black raspberry. The forms isolated from grasses 
 were obtained by partially disinfeoting the seeds with Javelle 
 water, in order to lessen the amount of Mucor, Altemaria, and 
 other saprophytes. The seeds were then placed in a sterile moist 
 chamber to germinate. After the seeds had grown for about three 
 days, those infected with the knee-formed type of Helminthospor- 
 ium could be recognized easily by their general appearance, and 
 these seeds were removed with sterile forceps and placed on corn- 
 meal agar. 
 
 IV. Methods of Study. 
 
 In order to simulate the conditions in which the 
 

 
 . 
 
 
 
 
 
 
 
 
 . 
 
 
 
 
 
 
 
 
 
 
 
 
-7- 
 
 fungus grows normally, a standard method of study was adopted. 
 
 The organism was planted on washed agar, nearly devoid of organic 
 material, and allowed to grow. After the colony had reached the 
 size of a dime, sterile wheat shoots, about two inches in length, 
 were placed on the agar. The sterile shoots were obtained by 
 growing aseptic wheat in sterile moist chambers until the shoot 
 reached a height of about two inches, when they were cut off, 
 placed in a vial and autoclaved. The cultures were kept in an 
 incubator at a temperature of 18 C. to 30 C. 
 
 In measuring the conidia a standard method, whereby 
 
 0 
 
 error would be reduced to a negligible minimum and the unconcious 
 selection of spores would be eliminated, was adopted. To prevent 
 the conidia from floating away or slipping from under the cover 
 glass, vaseline was used. With a dissecting needle, two smears 
 of vaseline were placed on a glass slide, separated from each 
 other far enough so that the smears would be just inside the 
 edges of the cover gla33. With a sterile needle, conidia were 
 placed in distilled water between the smears of vaseline and 
 covered with the cover glass. A Leitz Wetzlar mechanical stage 
 was used and only conidia which were in a predetermined position 
 in the field were measured. A Spencer ocular micrometer with a 
 movable scale was used in all measurements. 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
- 8 - 
 
 V. Descriptions of the Forms Studied. 
 
 % 
 
 In studying the culture characters, such as color, 
 zone formation, aerial and submerged mycelium, etc., of these 
 various forms, corn-meal agar, prepared according to the formula 
 of Shear and Stevens (4) , was used. 
 
 The plan followed in presenting the data is that of 
 describing one organism, No. 25, and then considering each of 
 the remaining organisms as to how it differs from the one fully 
 described. Fungus No. 25 shows a very faint zonation. The colony 
 when three or four days old has a whitish appearance, but it turns 
 to grayish-black as it matures. The submerged mycelium is hyaline 
 and much septate, the cells varying from 3.5 to 7.1 p. in width 
 and from 17.9 to 25 p. in length. The aerial mycelium is of a 
 light gray color, with the cells ranging from 3.5 to 7.1 p, in 
 width and from 14.2 to 30 u in length. For the sake of conven- 
 ience in describing the conidiophores , the terms stalk and sporo- 
 genous region are used. The former refers to the part between 
 the mycelium and the place where the conidia are borne, and the 
 latter to the part where the conidia are produced. The conidio- 
 phores, arising as simple, very rarely branched outgrowths or 
 branches of the mycelium, are variable in color and length. The 
 young conidiophores are from 3.5 to 17 p. long and 3.5 p. wide, and 
 they lack the knee-formed sporogenous region which is characteris- 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
-9- 
 
 tic of the older ones. In color they differ but very little 
 from the mycelium. The older conidiophores are pale straw color, 
 from 14.2 to 186 p. in length and from 3 to 6 p, in width. The 
 sporogenous region is from 3 to 71 p. in length and from 3 to 6 p 
 in width, while the stalk is from 11 to 165 \i in length and is 
 approximately 3,5 |i in width. The stalk and sporogenous region 
 are often of approximately the same length, and as a rule each 
 is divided into five or more cells. The sporogenous region pre- 
 sents a very crumpled appearance with many close geniculat ions, 
 and is of a lighter color than the stalk of the conidiophore. 
 
 The place of attachment of the conidia on the conidiophores is 
 easily recognized by the scars on the sporogenous region. These 
 scars vary from one to twelve or fifteen in number, depending 
 upon the age of the conidiophore. At first glance the conidia 
 appear to be borne in a head, but upon closer examination one 
 can see that when the first conidium is formed the main branch 
 ceases to grow. The conidiophore, therefore, grows out laterally 
 from near the base of the conidium and on the branch a new conid- 
 ium is formed. This process may be repeated many times. 
 
 A graph representing the conidial length is shown in 
 Plate I. The modal length is 21.4 ijl, with few conidia of shorter 
 length than the mode, but with many conidia of greater length 
 than the mode, the largest measured being 46.4 uu The width of 
 the conidia is represented in the polygon in Plate II, with most 
 
 

 
 
 
 
 
 
 ■ 
 
 
 
 
 
 . 
 
 
 
 
 
 
 
 
 
 
 
- 10 - 
 
 of the conidia between 7.1 and 10.7 n. The conidia, as shown 
 in Plate III, are usually three or four septate. The apical 
 end of the conidium is obtuse and the base is somewhat acute. 
 
 The basal cell is easily identified by the stipe which marks 
 the place of attachment to the conidiophore. The walls of the 
 conidia are very brittle, as is shown by the fact that a very 
 slight tap on the cover glass is sufficient to crush them, 
 causing the contents to pass out. The conidia are characterized 
 by their knee-formed appearance or geniculation. This genicula- 
 tion, which is due to a greater growth on one side than on the 
 other side of the conidium, is much more pronounced in some 
 conidia than in others. In a van Tieghem cell the conidia ger- 
 minate in water in from three to six hours. Each terminal cell 
 of the conidia sends out a germ tube, while the remaining cells 
 fail to show this phenomenon. When young, the conidia are green- 
 ish-brown in color and are remarkably uniform in this respect. 
 
 When mature they become darker, and then the end cells are very 
 much lighter in color than the intervening cells. 
 
 With respect to colony character, Nos. 29 and 31 are 
 very similar to No. 25 in color, though No. 29 is perhaps a little 
 darker. In zonation these forms also agree very closely. No. 27 
 has a very definite zonation and a grayish-brown color. No. 28 
 has a definite zonation. The colony is of an olive-drab color, 
 and the mycelium has a ropy appearance, that is, twisted into 
 

 ijj *»•? ■' ■ UUflE 
 
 ,^L.J 
 
- 11 - 
 
 masses at the ends. No. 30 has a fairly abundant growth of 
 mycelium, dark olive-drab in color. The zonation is scant, but 
 differs from the other races in regard to the growth of mycelium, 
 which will be discussed later. No. 32 is dark olive-drab in 
 color, with marked zonation, and a rather large growth of aerial 
 mycelium. This last character is not very marked in the other 
 forms, although they do exhibit it to some extent. The submerged 
 and aerial mycelium are alike in all of the forms. No. 27 differs 
 from the other forms in conidiophore character, this being 
 branched, while in the other forms it is simple. No difference 
 in character of conidiophores or the place of attachment was 
 noticed. The relation of the various forms as regards conidia, 
 conidiophores, and cultural characters is shown in Tables 1 and 3. 
 
 From the accompanying curves, Plate I, it may be seen 
 that there is some difference between the various forms in conid- 
 ial length. Organism No. 25 is set apart somewhat from the rest 
 by the modal length of its conidia. The conidia of No. 37 have 
 a modal length of 36 p; those of No. 28, the largest of those 
 studied, a modal length of 32 p. Nos. 39, 30, and 31 all fall 
 virtually in the same class, with a modal length of 25 p. No. 32 
 is of a somewhat different type, as is shown by the fact that 
 as many conidia measure 26 and 29.5 p as measure 33 p, which is 
 the modal length. From the study of the graphs showing conidial 
 length, Plate I, it appears probable that at least three, and 
 

 
 
 
 ' 
 
-13- 
 
 perhaps four, different forms or elementary species are repre- 
 sented. Further investigation is necessary, however, before 
 this conclusion may be drawn. 
 
 Plate II shows the width of the conidia to range from 
 7.14 to 14.3 |jl, with the majority measuring 10.7 y. From the 
 polygons, Plate III, showing septation, it can be seen that the 
 septa vary from one to four, but the most of the conidia are 
 four-septate. Because of the similarity in conidial width and 
 septation, as is shown in Plates II and III, these characters 
 do not differentiate one form from another. The apices and base 
 of the conidia in the various forms were alike, as far as deter- 
 mined, so none of these forms could be set apart from others by 
 these characters. The color of the conidia in all of the forms 
 is the same when the conidia are mature. 
 
 VI. Variations. 
 
 In studying the various forms as they grew on corn- 
 meal agar. No. 30 exhibited certain characters which were dis- 
 tinctly different from those of the other cultures. In No. 30 
 certain sectors of the colonies were very much darker than the 
 rest of the colony. In order to ascertain whether these darker 
 sectors were of permanent character, several experiments were 
 made. Transfers from many of the darkened sectors, as well as 
 

 
 ' ■ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
- 13 - 
 
 from the rest of the colony, were made and the results noted. 
 
 The transfers from the dark areas always failed to retain this 
 character, which was so evident when they were planted on the 
 culture medium, and reverted to the color of the original colony. 
 Transfers made from the original colony continued to produce 
 occasional dark areas, but when transfers were made from these 
 dark sectors the resulting colony showed a reversion to the 
 characters of the original mycelium. These experiments were 
 repeated many times, and in every case the sectors fluctuated 
 back and forth with respect to this character and gave evidence 
 of permanency. 
 
 VII. Conclusions. 
 
 From the descriptions of the forms listed above it 
 is plainly evident that only races, varieties or elementary species 
 of the genus Helminthosporium are enumerated in this paper. Since 
 the conidia are borne one above the other in a sympodial manner, 
 it is certain that Acrothecium and Brachysporium can be dismissed 
 as being genera in which the described forms may be placed. In 
 the genus Acrothecium the conidia are borne in a head at the end 
 of the conidiophore , and this character alone throws this genus 
 out of consideration. The genus Brachysporium, according to 
 Lindau (2), is characterized by having conidia that are not more 
 than twice as long as wide. From the graphs, Plate I, and poly- 
 

 s 
 
 ■ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 I 
 
-14- 
 
 gons, Plates II and III, which show very conclusively that the 
 conidia in the forms studied do not fall into this category, it 
 is evident that this genus can also be dismissed from considera- 
 tion. With these two genera eliminated Helrainthosporium only 
 remains. Stevens (5), in mentioning the last four forms studied, 
 says that they agree very closely with each other and according 
 to spore measurement approach H. inaequale Shear, H. tritici 
 P. Henn. , and H. geniculatum T. & E. Further study of these 
 forms is necessary before the status of these species may be 
 
 known. 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
-15- 
 
 VIII. Literature Cited. 
 
 (1) Saccardo, P. A. Sylloge Fungorum Omnium Hucuaque 
 
 Cognitorum. 18:828. Padua. 1910. 
 
 (2) Lindau, G. in Engler and Prantl, Die Naturlichen 
 
 Pflanzenf amilien. 1: Leipzig. 1900. 
 
 (3) Clements, F. E. The Genera of Fungi. Minneapolis. 
 
 1909. 
 
 (4) Shear, C. L. , and Stevens, N. E. Cultural characters 
 
 of the chestnut blight fungus. Bur. PI. Ind. 
 Circ. 131. 1913. 
 
 (5) Stevens, F. L. The Helminthosporium foot-rot of 
 
 wheat, with observations on the morphology of 
 the genus Helminthosporium and of the occurrence 
 of saltation in the genus. To be published in 
 the 111. Nat. Hist. Sur. Bull. 
 
-16- 
 
 Table 1. 
 
 Conidia 
 
 No. of 
 
 fungus Length in microns Breadth in microns 
 
 
 Mode 
 
 Mini- 
 
 Maxi- 
 
 Mode 
 
 Mini- 
 
 Maxi- 
 
 
 
 mum 
 
 mum 
 
 
 mum 
 
 mum 
 
 35 
 
 21.42 
 
 14.28 
 
 42.84 
 
 7.14 
 
 7.14 
 
 14.28 
 
 27 
 
 28.56 
 
 10.71 
 
 39.27 
 
 110.71 
 
 7.14 
 
 14.38 
 
 28 
 
 35.7 
 
 17.85 
 
 42.84 
 
 10.71 
 
 7.14 
 
 14.28 
 
 39 
 
 35.99 
 
 14.28 
 
 39.27 
 
 10.71 
 
 7.14 
 
 10.71 
 
 30 
 
 25.99 
 
 18.85 
 
 46.41 
 
 10.71 
 
 7.14 
 
 14.28 
 
 31 
 
 25. 99 
 
 10.71 
 
 46.41 
 
 10.71 
 
 7.14 
 
 14.28 
 
 32 
 
 32.13 
 
 14.38 
 
 43.84 
 
 10.71 
 
 7.14 
 
 14.28 
 
 Septa 
 
 1 to 4 usu- 
 ally four 
 
 3 to 4 usu- 
 ally four 
 
 3 to 4 usu- 
 ally four 
 
 3 to 4 usu- 
 ally four 
 
 1 to 4 usu- 
 ally four 
 
 3 to 4 usu- 
 ally four 
 
 1 to 4 usu- 
 ally four 
 

 
 
 
 
 
 
 . 
 
-17- 
 
 i 
 
 Table 2. 
 
 Conidiophores 
 
 No. of 
 
 ngus 
 
 Stalk 
 
 Sporogenous 
 
 
 
 region 
 
 
 
 
 Length 
 
 Length 
 
 Nc 
 
 i. of 
 
 
 in |jl 
 
 in |jl 
 
 soars 
 
 25 
 
 11 to 
 
 3.57 
 
 1 
 
 to 12 
 
 
 165 
 
 to 46 
 
 OI 
 
 ■ 15 
 
 27 
 
 7.14 to 
 
 7.14 
 
 1 
 
 to 13 
 
 
 150 
 
 to 42.8 
 
 
 
 28 
 
 7.14 to 
 
 7.14 
 
 1 
 
 to 12 
 
 
 171 
 
 to 71.4 
 
 
 
 29 
 
 10. 71 to 
 
 7.14 
 
 1 
 
 to 11 
 
 
 111 
 
 to 42 • 8 
 
 
 
 30 
 
 7.14 to 
 
 7.14 
 
 1 
 
 to 10 
 
 
 150.6 
 
 to 54 
 
 
 
 31 
 
 10. 71to 
 
 3.57 
 
 1 
 
 to 10 
 
 
 164 
 
 to 46.4 
 
 
 
 32 
 
 5.36 to 
 
 7.14 
 
 1 
 
 to 12 
 
 
 157 
 
 to 42.8 
 
 
 
 Culture Characters 
 
 Zona- 
 
 tion 
 
 Aerial 
 
 mycel- 
 
 ium 
 
 Color of 
 colony 
 
 Density 
 
 Very 
 
 scant 
 
 Gray 
 
 Grayish- 
 
 black 
 
 Sparse 
 
 Defin- 
 
 ite 
 
 Gray 
 
 Grayish- 
 
 brown 
 
 Medium 
 
 Defin- 
 
 ite 
 
 Gray 
 
 Olive- 
 
 drab 
 
 Medium 
 
 Scant 
 
 Gray 
 
 Light 
 
 grayish- 
 
 brown 
 
 Medium 
 
 Medium 
 
 Gray 
 
 Olive- 
 
 drab 
 
 Medium 
 
 Scant 
 
 Gray 
 
 Grayish- 
 
 brown 
 
 Medium 
 
 Defin- 
 
 ite 
 
 Gray 
 
 Dark 
 
 olive- 
 
 drab 
 
 Medium 
 
- 18 “ 
 
 
 
 Plate I. Graphs showing lengths of oonidia in Nos 
 25, 27, 28, 29, 30, 31, 32. Each space on the ab- 
 scissa equals 3.57 p.. 
 
-19- 
 
 Plate II. Polygons showing widths of conidia in Nos. 
 
 25, 27, 28, 29, 30, 31, 32. Each space on the abscissa 
 equals 3.57 u. 
 
 Plate III. Polygons showing septation in conidia in 
 
 Nos. 25, 27, 28, 29, 30, 31, 32. Each space on the 
 abscissa represents one septum. 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
- 20 - 
 
 4P 
 
 r/> ctT 
 
 % 
 
 ry 
 
 Plate IV. Showing conidia of No. 25. 
 
 Plate V. Showing conidia of No. 30.