May 26, X923 
Graminicolous Species of Helminthosporium 
717 
before their identity with the corn leaf-blight fungus can be regarded as 
definitely established. 
Very little experimentation seems to have been done on methods of 
controlling leaf blight. Most writers, apparently on general grounds, 
have recommended rotation of crops and sanitary measures like the de¬ 
struction of stubble and other refuse of diseased plants, the avoidance 
of manure containing diseased material, and even the roguing of infected 
growing plants. Ducomet {34) believed that spacing the plants at wider 
intervals might have a beneficial effect by encouraging aeration; while 
Ferraris (40) advised the treatment of seed with fungicidal solutions. 
Until definite information on the overwintering of the parasite, and, more 
particularly, information concerning the possible existence of an asciger- 
ous or sclerotial stage is available, no additional methods of combating 
the disease can well be suggested. 
Since this paper was submitted for publication, a lengthy account of 
the Helmintlmosporium diseases of maize and sorghum in India has been 
published by Mitra (91a). Helminthosporium turcicum is reported to be 
of widespread occurrence on both these hosts, although certain facts 
regarding its distribution were held to indicate that the parasite on 
sorghum represents a strain biologically distinct from that on maize, 
wi^ which, however, it is morphologically identical. It is interesting to 
note that Mitra observed that spores derived from the glumes of male 
spikelets are longer and more distinctly curved than fiiose found on 
diseased foliage. In cultural characters as well as in pathogenesis, this 
author failed to discover any differences between the two types, and 
consequently regarded both as belonging to the same species. 
Although it is evident that, for the most part, Mitra undoubtedly was 
dealing with the same parasite as that commonly attacking sweet com 
in the northeastern States, in order to forestall possible confusion, it 
may not be superfluous to call attention to certain discrepancies in 
morphological detail, even if these can not be very satisfactorily explained. 
Mitra states that typical spores of H. turcicum Pass, are spindle-shaped 
and pointed,^* and in some of his figures (p/a, PL 2, fig, 12, 16, PL j, fig, 
7, 8, 9) these structures are represented with both ends acutely pointed. 
As has been suggested in another connection, the writer has never 
observed conidia of any species of Helminthosporium thriving on maize, 
or, indeed, on any graminaeceous host whatsoever, in which such a con¬ 
dition is realized. While in American material of the maize blight 
fungus, the conidia with strongly tapering proximal portion and pro¬ 
truding hilum, might not improperly be described as pointed at the 
basal end, the apical end is never pointed, but is always rounded off 
either bluntly or more narrowly, depending on the degree of tapering 
exhibited by the distal segments. Perhaps Mitra may have been 
influenced to some extent by the erroneous drawings of Saccardo and 
Massee. No mention is made of the presence of the hilum, a number of 
figures (pra, PL 2, fig, 6, 22 to 25, PL 5, fig, ii) clearly showing no indi¬ 
cation of this protruding modification. 
According to the account given by Mitra, germination is often asso¬ 
ciated with a breaking dovm of the internal partitions of the spore. 
Judging from his figures of conidia, in which the peripheral wall is fre¬ 
quently represented as a thick envelope (91a, PL 2, fig, 6 to 10, 14 to 17, 
PL jf fig- 7 to ii ), it is evident that a not inconsiderable proportion of 
the spores employed by him were entirely dead, while others must have 
contained one or more dead segments. In the writer's experience, only 
