PARASITOLOGY. 79 
cyst by migration, and if they reach the bronchi may 
be expelled with mucus through fits of coughing, and 
thus soil the feed or water. In the adult state the 
parasites infest the nasal chamber, and possibly the 
pharynx and larynx. They hold on to the mucous 
membrane by means of hooklets and produce an 
inflammation which is accompanied by a muco-puru- 
lent discharge. The animal sneezes, scratches and 
rubs its nose, etc. 
FUNGI. 
The fungi that attack animals are vegetable para- 
sites and are similar to the common moulds in their 
general appearance and method of reproduction. 
Reproduction is by spores, which are small round 
bodies, microscopic in size, resembling small seeds. 
The filaments, or hyphae, consist of a series of cells 
arranged end to end. These cells consist of a cell 
wall and protoplasm. The spores have a greater 
resistance to unfavorable conditions than the mycelia, 
and when placed under favorable conditions, or “fer- 
tile ground,” produce the hyphae. 
TRICHOPHYTON TONSURANS (Trix—hair ; phyton, a plant.) 
(Tonsurans—to shear.) 
Disease. —Tinea tonsurans: circinate ringworm; 
ringworm. 
Animals Intested.—Man, horse, ox, hog, dog, cat, 
sheep, and bird. 
Symptoms.—The affected spot is at first red; it 
gradually enlarges and is covered with a thin, gray- 
ish scale, under which is found serum. The hair is 
cut off at the surface as a result of the invasion of 
the skin by the fungi. The circumference is red, 
