678 
Journal of Agricultural Research 
Vol. XXIV. No. 8 
teres on barley. The newly affected green tissues show abundant brown¬ 
ish discoloration in irregular patterns, within which may be recognized 
a network of darker longitundinal and transverse linear streaks. (PI. 
II, A, C.) The minute reticulate design formed by the latter is, in well 
developed cases, more extensive and pronounced than in any specimens 
of barley affected with netblotch which the writer has ever seen. After 
a considerable portion of the leaf blade has been involved, it gradually 
withers and dies, the withering beginning at the tip and proceeding 
toward the base. (PI. ii. A.) In 1920, in the neighborhood of New 
York City, such destruction of foliage continued throughout nearly the 
entire season, and caused an amount of damage that appeared to be 
far from trivial. Indeed, the writer is inclined to believe that the malady, 
which may conveniently be designated like that caused by H, teres^ as 
netblotch, is the most serious parasitic trouble affecting meadow fes¬ 
cue in our northern latitudes. 
On examining the withered portions of affected leaf blades, the cause 
of the disease is readily recognized as a species of Helminthosporium. 
To H. teres, however, the fungus shows no close similarity, the spores of 
the barley parasite having dimensions so much greater as to preclude 
any possibility of confusing the two forms. It shows a much greater 
degree of similarity to H. gramineum. The sporophores, as in the stripe 
fungus, are found in groups larger than in most congeneric species, the 
number in a group varying usually from 2 to 6 (PI. ii, Ea-i). On the 
other hand, lie basal enlargement characteristic of the sporophores of 
H. gramineum appears to be less pronounced in the homologous struc¬ 
tures of the form on meadow fescue. The spores of the two fungi possess 
some characteristics in common, but exhibit quite distinctive specific 
differences as well. Thus they agree in color, in both species varying 
from subhyaline and colorless when newly proliferated, to distinctly 
yellowish when fully mature; and on measuring show an approximately 
equal range in length. However, the spores of H, gramineum are appre¬ 
ciably greater in diameter, and, while manifesting a tendency to taper 
toward the apex, do not depart very greatly from a straight-cylindrical 
type, whereas those of the parasite on Festuca elatior (PI. ii, Ba-q) more 
frequently show a very pronounced diminution in diameter from the 
base to the tip, and in only relatively few instances approach an approxi¬ 
mately cylindrical shape. In germinating the conidia of the fungus on 
meadow fescue do not generally produce germ tubes indiscriminately 
from both the end and the middle segments, but typically give rise to a 
lateral or oblique germ tube from one or both end segments (PI. ii, 
Dc-k), although, less frequently, one or more gerin tubes may be pro¬ 
duced from a middle segment (PI. ii, Da-b). It als© may be mentioned 
that the spontaneous development from primary spores of short sporo¬ 
phores bearing secondary spores, characteristic of the barley stripe 
fungus, has not been observed in any material of the parasite on meadow 
fescue. 
Another congeneric form with which the species of Helminthosporium 
on Festuca elatior might possibly be confused is the one described in 
this paper as H. siccans that occurs on Lolium multiftorum Lam. and 
L. perenne L. The latter on comparative examination, however, is 
readily distinguished by the appreciably larger dimensions, conspicu¬ 
ously darker coloration, and less tapering form characteristic of its 
conidia. These conidia when altogefiber mature possess, moreover, a 
considerably thicker peripheral wall, and, in germinating, typically 
produce two germ tubes from each of the end segments instead of one. 
