664 
Journal of Agricultural Research 
Vol. XXIV. No. 8 
parasite as a separate taxonomic entity necessitated the perpetuation of 
their form name as the specific name, adopted the combination H, 
avenae (Br. & Cav.). The last portion of the form name— sativae — ^he 
omitted purposely on the ground that it was unnecessary. Lindau (<?j, 
p- 34-33) y presumably because of the patent irregularity in altering a 
name in such manner, recognized Briosi and Cavara’s form name without 
alterations as the proper specific name, and consequently listed the 
fungus as H. avenae-sativae (Br. 8c Cav.). However, as the use of an 
earlier varietal name to replace a specific name (when the variety is 
raised to specific rank) is not sanctioned by present usage, it is obvious 
that both Ravn’s and Lindau's combination are equally unauthorized, and 
that the proper combination is evidently the one established by Eidam. 
In this connection, it may be mentioned that Cooke (25), in 1889, 
described as Helminthosporium avenaceum Curtis Herb., a fungus occur¬ 
ring on straw in the United States (oat straw according to Saccardo) the 
conidia of which were characterized as cylindrical to subfusoid, pale 
honey-colored, and measuring 75 to 85 by 15 fi. Harkness (50) mentioned 
H, avenaceum Curt, as having been found on Avena, at San Francisco, in 
April. Atkinson (4) records having collected a fungus to which he 
applies the same name, in Mississippi, on June 26, 1891. It is not im¬ 
possible that these authors were dealing with the fungus originally de¬ 
scribed from Italy, inasmuch as the brief diagnosis published by Cooke 
is not greatly at variance with that of Briosi and Cavara, and in purely 
morphological details nearly as satisfactory for the parasite causing leaf 
spot of oats as the latter. Since in none of the American writings was the 
fungus associated with any lesions in the living plant, such possible 
identity can not readily be established. The question is further compli¬ 
cated by the occurrence of forms of Helminthosporium, associated with 
sclerotia appearing saprophyticaUy in considerable quantity on oat 
straw in spring, and evidently representing immature perithecia of 
Pleospora or F^enophora. The writer has investigated two such forms 
collected near Madison, Wis., in 1919 and 1920, one of which seems to be 
similar to or identical with H, avenae, while the other is entirely different, 
its small, dark olivaceous, strongly curved, 5-septate spores germinating 
by the production of 2 polar germ tubes. Further details may be pub¬ 
lished in a later paper. 
In 1895, Harvey {31) published a brief account of a disease of oats 
found in Maine during the preceding two seasons, manifested apparently 
by premature yellowing of the foliage, and the subsequent production of 
dark brown spore masses that appeared as small dark dots or lines upon 
the affected leaves. The fungus in question was a species of Helmin¬ 
thosporium, which Ellis, to whom material was sent, identified as 
Helminthosporium inconspicuum C. & E. var. brittanicum Grove. 
Unfortunately, however, as the only statement regarding the host rela¬ 
tionship of Grove’s variety in the diagnosis given by Saccardo {128, v. 4, 
p. 411-412) refers to fading grass leaves wiQiout any mention of species 
or genus, it is quite impossible, with the paucity of morphological detail, 
to identify it with any one of a considerable number of fungi. 
Ellis’s identification might be supposed to indicate that the Maine 
fungus corresponded in some measure with the diagnosis of the War¬ 
wickshire form: 
Efftisum bnmeolum, hyphis subflexuosis, vix nodulosis, 4-5 septatis, pallide 
brunneis, 160-180=10 m; conidiis elongis, diaphanis, endochromate brunneolo diviso, 
dein 3-5 septatis, 60-100=18-22 jii.^ 
