[Vor. 3 
248 ANNALS OF THE Missourt BOTANICAL GARDEN 
tral nervous system, but he obtained no cultures of the 
organism. 
The spores of fungi, introduced by injection into the 
blood-vessels, are carried by the blood into all parts of the 
body. They do not germinate in the blood current itself, 
but only in certain organs of the animal into which they are 
conveyed by the blood. The living organs show different 
degrees of liability to the attack of the fungus, especially 
when the spores are injected in small quantities. Lichtheim 
(’82) arranges the susceptibility of the various organs to 
Mucor in the following descending series: kidneys, Peyer’s 
patches, mesenteric glands, spleen, marrow, and the liver. 
After the death of the animal there is no difference in the 
rate of germination and development of the fungus in the 
organs. The development of the fungus is attended by 
characteristic local derangements, and these produce dis- 
turbances of the general health. Sticker (’00) asks the ques- 
tion whether or not the large amount of carbon dioxide 
formed by the development of the fungus does not cause the 
injurious effects on the animals. Others believe that a fer- 
mentative action plays an important róle. Spontaneous As- 
pergillus and Mucor mycoses in internal organs removed 
from the direct access of air are, to say the least, a doubtful 
occurrence. 
Grawitz (’77) attempted to produce infection in dogs and 
rabbits by inoculations with spores of Mucor Mucedo, M. 
racemosus, and Rhizopus nigricans. None of the two hun- 
dred animals used died from the effects of these treatments. 
Experiments of Lichtheim (’82) and Lindt (’86) indicated 
that Mucor corymbifer, M. pusillus, and Rhizopus Cohnii 
were pathogenic for certain animals. However, none of 
the species of Mucor and Aspergillus when injected into 
the blood system of animals gave rise to fructifications in the 
tissues. Lichtheim pointed out that the negative results of 
other investigators were to be expected, since all species of 
Mucor and Aspergillus are not pathogenic. His predecessors 
had experimented with diverse species, impure cultures, or 
with fungi inexactly determined. 
