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Beyond these three facts there is practically little or nothing in 
which there is entire accord. 
Pornts of DISAGREEMENT 
These may be summarized as follows: 
Symptoms.—Many observers describe as an essential symptom of 
foot-rot the presence of a brown felt-like mycelial weft on the diseased 
stem and adjacent sheath. Some describe it as a black crust. Others 
fail to find this, or at least do not mention it, while still others definitely 
assert that it is not an essential symptom. 
Some describe the roots as swollen, blackened, or stunted, though 
most writers mention no root symptoms. 
Most writers assert that if land on which the disease occurs is 
cropped with wheat the following year the disease will again appear, 
and often on a largely increased area. Some show by experiment that 
wheat planted in diseased stubble will become diseased; others say that 
succeeding crops may be healthy, and that the recurrence of the disease 
is dependent upon various factors, chief among which is the weather. 
Etiology—Most writers on foot-rot say that the causal fungus is 
Ophiobolus graminis; a smaller number that it is O. herpotrichus. Some 
merely report the presence of one or both of these fungi, while other in- 
vestigators claim to have demonstrated their actual parasitism by inocu- 
lations with pure or nearly pure cultures of one or another of these 
fungi. Other writers claim that Leptosphaeria herpotrichoides, Typhula 
graminis, and Cladosporium herbarum are causal agents of foot-rot, 
while some assert that any one of several of the five fungi mentioned 
above may be the cause of the disease. 
Some hold that these fungi are saprophytes or but weak parasites 
that can attack the wheat plant only when it is weakened by other causes, 
chiefly by cold. 
Conidial stages of Ophiobolus—Various claims have been made as 
to the conidiai form of Ophiobolus. Some state that the fungus is 
usually sterile in its young stages. Some find as the conidial form a 
Coniosporium, an Acremonium, a Fusarium, or a Hendersonia. 
Various prophylactic measures, as burning stubble, rotation, good 
culture, etc., have been suggested, but they are based on general grounds 
rather than specific knowledge of this disease, and will not be discussed. 
In view of these conflicting observations and conclusions the most 
reasonable attitude is that of Prunet, Voges, and others, namely, that 
we have here several distinct diseases due to as many separate causes. 
Clearly science will be best served by such a conception. 
So far as I can judge, the disease now present in Madison county, 
Illinois, is indistinguishable from that described by Cordley in Oregon, 
U.S. A., in 1902 (75), the cause of which he did not determine. I am 
not yet sure what the cause of the Madison county disease really is, but 
