COCCIDIUM BIGEMINUM 8l 



intestinal lumen is sometimes entirely filled with free parasites, and 

 frequently more than one schizont is met with in each epithelial 

 cell. In such severe cases death occurs after a few days, in 

 milder cases the diseased animals sink gradually, or may spon- 

 taneously recover. 



FIG. 33. Coccidium hominis (Riv.) in sporulation. (After Riek.) 



The coccidia observed in the intestine of the horse, goat, ox, 

 sheep, pig, mole, marmot, guinea-pig and weasel are generally 

 regarded as varieties of Coccidium hominis, i.e., C. perforans. 



Eimer found the intestinal epithelium of two cadavers of human beings of the 

 Pathological Institute in Berlin permeated with coccidia (Die ei. u. kugelf. Psorosp. 

 1. Wirbelth., 1870, p. 16). Railliet and Lucet's case was undoubtedly attribut- 

 able to intestinal coccidia. In this case a woman and her child had both 

 been suffering from chronic diarrhoea for a long time, and coccidia were 

 found in the faeces of both (Railliet, Trait Zool. med. et agric., 1893, 2nd 

 edition, p. 140). In other cases (Grassi, Rivolta) in which only the occur- 

 rence of coccidia in the faeces is reported, the origin of the parasites 

 whether from the intestine or liver remains doubtful, and likewise also- 

 the species to which they belong. 



3. Coccidium bigeminum, Stiles, 1891. 

 Syn : Cystospermium villorum intestinalium canis et felis, Rivolta, 1874. 



This species has been known since 1854 (Finck, Sur la phys, 

 de Vcpith. intest., These, Strasburg, p. 17) ; it lives in the intes- 

 tinal villi of dogs, cats and the pole-cat (Mustela putorius, L.), 

 and is distinguished by its small size and its constant appearance 

 in pairs. According to Stiles, 1 the oocyst divides into two equal 

 portions which become encysted and then form four spores. The 

 oocysts of this species attain a length of 0*012 0-015 mm. and 

 a breadth of 0-0070-010 mm. in the dog, only 0*008 0*010 by 

 0-007 0-009 mm. in the cat, and 0-008 0-012 by 0*006 0-008 mm. 

 in the pole-cat. 



' Stiles, Ch. W., " Notes on paras.," No. n (Journ. of Comp. Med. and Vet. Arch., 

 1892, xiii., p. 517). 

 6 



