Oct. 15,1925 Leaf spot of Maize Caused by Ophiobolus heterostrophus 721 
culture and pathogenicity only serve to confirm, however, the very 
clear evidence provided by the frequent presence on the perithecium 
of a larger or smaller number of conidiophores bearing conidia typical 
of the leafspot fungus and arising unmistakably from the perithecial 
wall (fig. 4, A). Sometimes the conidial fructifications arising in this 
manner become very abundant, with the usual result that the internal 
differentiation of the fruiting body is largely if not entirely sup¬ 
pressed. 
CLASSIFICATION OF PARASITE 
In reference to Saccardo’s system, the fungus is presumably to be 
reckoned among the scolecosporous Sphaeriaceae, by virtue of the 
relative dimensions of the ascospores rather than because of any 
close similarity to the usual filamentous type. Among the definitions 
of the genera included in this category, none contain any special 
provision for the most noteworthy characteristic of the fungus—the 
disposition of the ascospore in a well-defined spiral. A considerable 
degree of similarity is discernible, however, to a fungus originally 
described by Saccardo {12) as Rhaphidophora camptospora, a com¬ 
bination later reduced by the author {IS, v. 2, p . 844) to a synonym 
of Ophiobolus camptosporus Sacc. Under the latter binomial, 
Berlese published illustrations {1, v. 2, pi. 159) and a somewhat 
altered description {1, v. 2, p. 133) based upon material supplied by 
Saccardo. Berlese’s figures show a short, stipitate, cylindrical ascus 
containing four spores partly coiled in helices in a manner strongly 
suggestive of the maize parasite, although the direction of rotation 
is opposite to that prevailing in the latter. In Ophiobolus campto¬ 
sporus one of the median segments in the ascospores is swollen, 
which would seem to show relationship to certain other forms assigned 
to Ophiobolus, as well as to species referred to allied genera exhibiting 
one or more nodose intermediate segments. 
Another fungus that should be mentioned in this connection is 
Ophiobolus chaetophorus (Crouan) Sacc., which, according to the 
account given by Malbranche and Niel {6 ), exhibits a spiral dispo¬ 
sition of its ascospores suggesting the elaters of certain slime molds. 
In the figures, the direction of rotation seems to be like that found 
in the maize parasite. As the asci are described as eight-spored, and 
the perithecia as provided with rigid bristles oy the upper part, 
differences from the latter organism are not lacking. 0. heticosporus 
(B. & Br.) Sacc. {13, v. 2, p. 350) with “sporidiis linearibus praelongis 
spiraliter convolutis” ana 0. galii Rich, with “sporidiis spiraliter 
fasciculatis, hyalinis” represent two imperfectly described species 
that may possibly be related. Malbranche and Mel state that the 
perithecia of 0. helicosporus are glabrous, thus differing in one 
particular from 0. chaetophorus, which Saccardo later referred to the 
genus Ophiochaete, erected to include definitely setose forms. 
According to recent publications by Hohnel {4, 5) and Weese {16), 
the genus Ophiobolus, as employed by Saccardo and other writers, is 
far From being a homogeneous group. HohneFs recommendations 
contemplated the maintenance of three genera—(1) Leptospora 
Rabh., based on L. porphyrogona (Tode) Rabh. to include not only 
“sphaeriaceous” forms having narrow spores with or without a 
nodose cell, but also species having somewhat broader many-septate, 
colored spores with nodose segments; (2) Entodesmium Riess, based 
on Entodesmium rude Riess, a “dothidiaceous” type, to include those 
