710 
Journal of Agricultural Research 
Vol. XXIV, No. 8 
HEMINTHOSPORIUM LEUCOSTYEUM, N. SP. 
In October, 1921, the writer collected specimens of Eleusine indica 
(L.) Gaertn. near Washington, D. C., some of the leaves of which were 
partially or wholly withered. Most frequently the tip alone was affected, 
but in other instances the blade was involved down to its juncture with 
the sheath. The dying portions of the leaf were characterized by the 
presence of small, irregular, poorly defined, reddish-brown spots, some¬ 
what suggestive of the discoloration produced by Helminthosporium 
avenae on the foliage of oats. 
On examining thoroughly withered portions of leaf which, like barley 
leaves affected with stripe, showed a pronounced tendency to split into 
numerous longitudinal shreds, fructifications of a fungus apparently 
referable to the genus Helminthosporium were found in moderate abun¬ 
dance. As these portions frequently bore also a considerable growth 
of undoubtedly saprophytic forms, mainly Altemaria spp., the spots 
previously mentioned were largely obliterated by miscellaneous local 
and diffused discolorations. It was consequently not possible to decide 
definitely as to the existence of any causal relation of the species of 
Helminthosporium, either to the withering observed or more particularly 
to the foliar lesions that appeared to be associated with it. To dis¬ 
tinguish the fungus from the congeneric forms, H, giganteum and H, 
cynodontis, occurring on the same host, as well as from H, nodulosum 
B. & C., an apparently widely distributed parasite attacking the inflo¬ 
rescence of goose grass, it may not be superfluous to include a brief 
account of its morphological features. 
The conidiophores (PI. 23, Ha-e, la-d) exhibit a particularly striking 
departure of the fungus from the type that appears to be common to 
most graminicolous species of Helminthosporium. Instead of growing 
to a considerable length before beginning to proliferate conidia, they 
develop the first spore while still relatively short. Owing to this initial 
economy and to the moderately short intervals between successive spores, 
the ultimate length of the sporophore is conspicuously inferior to that 
of most congeneric species. Perhaps quite as remarkable is the absence 
of the usual deep olivaceous color from these structures, which are, gen¬ 
erally, nearly colorless or of a light fuliginous tinge. It is interesting to 
note, besides, that the sporophores, like those of H, turcicum, appear to 
emerge only from the stomata, and in relatively large groups. 
The conidia (PI. 23, Ja-r), which resemble those of Helminthosporium 
sativum and many other species in being of a deep olivaceous color, in 
the possession of a thick peripheral wall, and in mode of germination, 
frequently show a pronounced tendency to taper toward the apex (PI. 23, 
Jg, i). Indeed, the writer was at first inclined to refer the species to the 
genus Napicladium because of this tendency. However, as in numerous 
instances a subcylindrical shape is approximated (PI. 23, Jb, p.), it 
appears better to refer it to the genus Helminthosporium, which, more¬ 
over, contains other species characterized by spores frequently tapering 
very perceptibly toward the apex, as, for example, H. gramineum. The 
attenuation of the peripheral wall at the places from which the germ 
tubes are destined to appear is very marked, being evidenced as in H. 
halodes and H. monoceras, for example, by small, altogether hyaline 
regions, one at the apex and another immediately surrounding the 
hilum. The germ tubes are relatively narrow, and, in elongating, more 
