ISOSPOEA. 167 



merozoites . There were numerous macrogametocy tes measuring 

 about 7-5 jLt in diameter. During life this dog passed in its 

 faeces numerous immature oocysts measuring 10-14 /x. by 

 7-5-9 )u,, the sporocysts measuring 7-5-9 ju, by 5-7 ju. In 

 another puppy a large number of odcysts of the same dimensions 

 were passed, and completed their development outside the 

 body in the usual manner, forming two sporocysts, each with 

 four sporozoites and a residual body. 



Wenyon (1926) is of the opinion that there are three species 

 of Isospora in cats and dogs, and gives the dimensions of the 

 oocysts as follows : — 



7. /eZis, 39-48 iLi by 26-37 /i. 



I. rivolta, 20-24 ^u by 15-20 ^it. 



/. bigemina (large), 18-20 /a by 14-16 jU,. 



I. bigemina (small), 10-16 ju. by 7-5-10 jU,. 



Dobell (1926) criticizes this view, but Wenyon (1926) 

 adheres to it. Reichenow (1929) recognizes these species as 

 distinct. According to Yakimoff, Matikaschwih, Rastegaieff, 

 and Lewkowitsch (1930) the domestic cat harbours three 

 species, viz., I. bigemina var. cati (Stiles), /. rivolta (Grassi), 

 and I. felis Wenyon. Sen (1932) noted an unidentified 

 coccidian from a dog at Muktesar. 



Habitat. — Subepithehal tissue of the intestine in dogs : 

 Ceylon, Colombo. 



97. Isospora ealotesi, sp. no v. 



■fisospora sp., Setna, 1933, p. 97. 



Schizonts spherical. Multiple fragmentation gives rise to 

 a number of small ovoid merozoites which gradually become 

 vermiform. Merozoites vary in size : there may be four large 

 merozoites clustered round a central cytoplasmic residue, 

 or a large number, up to about 100, of slender fusiform mero- 

 zoites. Male and female gametocytes may develop in the same 

 epithelial cell or in separate ones, and in the earher stages are 

 difficult to distinguish from the schizonts and from one 

 another. 



Remarks. — The developmental stages are clearly marked off, 

 and as many as 80 per cent of the hzards examined were 

 infected. Infection was Hmited to the epithehum ; the sub- 

 epithelial tissue was not affected. 



Dimensions.' — Schizonts up to 22 ;u, by 17 )u,; merozoites, 

 small and slender 9)u, by 1-2 ^u,, large 8ju, by 2-8 ju,. 



Habitat.' — Intestine of the lizard, Calotes versicolor (Daudin) : 

 Bombay, Bombay. 



