1916] 
Emic—Yerast Funai 249 
Birds are very susceptible to aspergillosis and succumb 
regularly after a time varying with the quantity of spores 
injected. Rabbits and guinea-pigs are susceptible to a less 
degree, and these animals can survive when they receive 
infections of a small quantity of fungous spores. Dogs, cats, 
and sheep are immune. 
More recently Lucet and Costantin (’00) have established 
the pathogenic nature of Mucor corymbifer. Rabbits suc- 
cumb to the spores of M. corymbifer three to twelve days 
after the injection of the spores, with lesions in the kidneys 
and mesenteric glands. The same authors affirm the patho- 
genic properties of Rhizopus nigricans (Rhizomucor parasit- 
icus). Intravenous and intraperitoneal injections of R. nigri- 
cams proved fatal to rabbits and guinea-pigs, but subcuta- 
neous injections were ineffective. 
The authors above mentioned assert that the intensity of 
the toxic action of fungi is proportional to the quantity of 
the fungous spores injected, and that in this manner it dif- 
fers from that of pathogenic bacteria in which the intensity 
of the toxic action is independent, to a large extent, of the 
number of bacteria injected into the animal. The toxic 
action of fungous spores is apparently not affected by chem- 
ical treatment or by heating for a limited time up to the 
thermal death-point. The fungous spores may germinate, 
but no multiplication of cells takes place in the tissues; con- 
sequently, in experimental mycotic infections there is no 
secondary generalization. "These mycotic colonies are not 
directly inoculable into other animals, and in order to infect 
another animal, it is necessary to ‘‘produce a new series of 
spores in contact with the air.’’ 
There are a large number of species of Mucor and Asper- 
gillus of wide distribution. The most common species of 
Mucor is M. Mucedo which is non-pathogenic for animals, 
as is also Rhizopus mgricans (Mucor stolonifer), a very 
widely distributed species which is often considered patho- 
genic. The species of fungi given below have been consid- 
ered as injurious to animals. The greater number of these 
species have been misdetermined, whereas the toxic action 
