FUNGI AND BACTERIA. 25 
samples have been found which, though they contained 
these moulds, were harmless. Such differential action 
might possibly be accounted for by assuming the pre- 
sence of different strains of the same species. An analog- 
ous case has been described by Dr. M. Otto, who found 
that while a strain of Aspergillus fumigatus from Italy 
was markedly poisonous, another from Germany was not 
at all, or only slightly so. The existence of similar strains 
of other common moulds has not, however, been demon- 
strated. 
A more promising line of attack has been from the 
bacteriological standpoint. The work was carried out at 
the Kentucky Agricultural Experimental Station by Gra- 
ham, Bruechner and Pontius. They isolated from mouldy 
hay that had caused typical cases of forage poisoning, a 
bacillus resembling B. botulinus, the organism of botulism. 
Like the latter it is an anaérobic bacillus but grows in air 
when accompanied by certain of the moulds usually found 
on forage. Pure cultures of the bacillus, fed to horses, 
mules and guinea pigs, produced typical cases of forage 
poisoning, similar to those caused by the hay from which 
it had been obtained. The disease is apparently caused 
by toxins produced for the most part, before the forage 
is eaten. In their experiments animals were poisoned 
from a single barrel of the hay, by water which had been 
poured over the forage and had dissolved some of the 
toxin. Since the bacillus in question closely resembled 
B. botulinus in appearance, anaérobic characters, and 
physiological effects, these investigators made further 
tests to determine, if possible, whether the two were 
identical. Antitoxic serum prepared from B. botulinus 
was procured and was found to produce immunity from 
the effects of the bacillus cultured from the poisonous 
