ANIMAL PARASITIC INFECTIONS 429 
about 2.5 em. in diameter. A piece of the tumor was preserved in Zenker’s 
solution. The study of stained sections of it has revealed nothing of special 
interest, the structure is that of a typical wart, with very marked increase of the 
epithelium, the horny layer being especially thickened and a number of epithelial 
pearls present. At the necropsy of this animal there were in both the spleen and 
liver irregular areas which were of a paler red color and particularly soft and 
friable. It was thought at the time that this condition might be due to a post- 

No. 356. — Photomicrograph of section of the spleen of hyena, Crocuta thomasi, showing 
postmortem infection with fungus. Zeiss objective DD, compensating ocular 6 
mortem invasion with Bacillus aerogenes-capsulatus. However, examination of 
stained sections of the spleen did not show any postmortem bacilli but on the 
contrary an extensive invasion of the organ with a fungus. Both mycelial and 
spherical forms of the parasite are present in many parts of the tissue. No 
mycotic infections of the spleen were observed in Africa, with the exception of 
several postmortem invasions of the organ with fungi. 
It may be of general zoological interest to mention that a single almost full- 
term foetus was found in the uterus of one hyena. Very little, of course, is known 
of the breeding of hyenas, which is said not to take place in captivity. Roosevelt 
