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Journal of Agricultural Research 
Vol. XXIV, No. 8 
elongated, dark brown spots, measuring usually o.i to 0.3 mm. in width 
and 0.2 to i.o mm. in length, although sometimes apparently as a result 
of coalescence, attaining dimensions several times larger. Many of the 
more severely affected leaf blades bore more than a hundred of these 
localized discolorations and frequently more than a dozen could be 
distinguished on the sheath, mostly near its juncture with the blade. 
(PI. 12, Ab.) Owing to the large number of spots often present on a 
single foliar organ, an appearance somewhat suggestive of netblotch 
is brought about, but as distinct transverse markings have not been 
observed, the reticulate pattern characteristic of leaves of barley and 
meadow fescue attacked by Helminthosporuim teres and i/. dictyaides, 
respectively, is not evident. It may be mentioned that the most dis¬ 
tinctive sharply defined discolorations have usually been found on leaves 
of younger plants, while on the leaves of plants attacked after the heading 
stage the discoloration frequently appeared to be somewhat suppressed. 
In any case, however, the organs attacked soon turned yellow at the 
tip and withered, the withering eventually involving the sheaths as well 
as the blades. 
Microscopical examination of leaves that had succumbed to the malady 
revealed an abundance of fructifications typical of the genus Helmintho- 
sporium emerging from the dead tissues. Although the symptoms of 
the disease caused by it are quite different from those of the stripe 
disease of barley, the fungus shows a strong resemblance to H. gramineum. 
The spores of ihe^ two species are nearly similar in shape, being usually 
straight and cylindrical or tapering toward the tip. The tendency 
toward tapering, to be sure, is more pronounced in the conidia of the 
parasite on Italian rye grass, which, moreover, when fully mature, are of 
a brown or brownish olivaceous color, appreciably darker than the yellow 
fuliginous hue characteristic of the spores of the stripe fungus. With 
this deeper coloration is associated a peripheral wall, decidedly thicker 
than the spore wall of subhyaline-spored types but inferior to that of 
species possessing olivaceous spores of the type of H. sativum. The 
conidia of the form on Lolium multiflorum are perceptibly longer than 
those of H. gramineum, and a proportional inequality obtains in regard 
to the spore segments of the two species. 
Germination in water normally takes place in a manner very similar 
to the germination in H. gramineum; that is, by the production typically 
of one or two germ tubes from both apical and basal segments and a 
single tube from several or all intermediate segments, although occasion¬ 
ally two tubes may be proliferated from an intermediate segment. The 
production of sporophoric processes by conidia under natural conditions, 
while not uncommon, is not as frequent in the fungus on L. multiflorum 
as in the stripe fungus, and apparently usually comes to an end with the 
production of a single secondary conidium. 
The form on Italian rye grass shows considerable resemblance to 
Helminthosporium dictyoides on meadow fescue, not only in general 
pathological habit but in morphological details as well. The conidia 
are largely of the same straight cylindrical or tapering form. They 
are noticeably larger, however, more frequently septate, and when fully 
mature darker and provided with a thicker peripheral wall. The mode 
of germination also shows some difference, the parasite on Lolium multi¬ 
florum being usually more profuse in the production of germ tubes. 
With the form described in this paper as H. stenacrum occurring on 
Agrostis stolonifera the fungus is not readily confused, being distinguished 
