204 PARASITOLOGY. 



till it increases to twenty; later there is developed 

 around this spherical mass a limiting membrane; as 

 the development progresses the protoplasm sepa- 

 rates from the cell wall ; it then divides into two, then 

 into four bodies called sporoblasts; each sporoblast 

 divides into two corpuscles. Each of the corpuscles, 

 under favorable conditions, becomes an amoeboid 

 individual, capable of invading epithelial cells. 



Animals Infested. — The ox, sheep, goat, pig, rabbit 

 and man. 



Parts Infested. — ^Epithelial cells of the intestinal 

 mucous membrane and liver cells. 



Name of Disease. — Coccidiosis. When the liver cells 

 are invaded it causes coccidian hepatitis. When 

 the intestinal epithelial cells are invaded it causes 

 intestinal coccidiosis. 



Condition Produced. — When the intestinal mucosa is 

 infested there is a fetid diarrhoea, an elevation of 

 temperature, loss of appetite, weakness, followed by 

 death. On autopsy there is found a thickened, red- 

 dened mucous membrane with ulcerated patches ; the 

 mesenteric lymph glands are enlarged. If the liver 

 is infested, small, round abscesses, varying in size to 

 a hazel nut, are observed; these abscesses are filled 

 with a thick, creamy or cheesy pus; the wall is thick 

 and the inner surface velvety in appearance; often 

 the liver is several times its normal size, thoroughly 

 studded with small abscesses. The carcass will be 

 in an emaciated condition. 



CocciDiUM BiGEMiNUM, Variety Canis (Bis — twice) 



(Canis — dog). 



Synonyms. — Tetrasporous Coccidia ; Cystosperm- 

 ium Villarum IntestinaUum Canis. 



