EIMERIA. 187 



membrane. Oocyst spherical, the cytoplasm dividing into 

 four sporoblasts without leaving any residuum. The four 

 sporocysts have clear contents. Each shows one smaller and 

 two larger spheres ; the two larger ones represent the larger 

 end of each of the contained comma-shaped sporozoites, and 

 the smaller one a residual body which is granular to start with, 

 but soon becomes transparent and refringent like the sporo- 

 zoites. 



Remarks. — The parasite differs from E. kermorganti in the 

 smaller dimensions of the oocysts and in the appearance of 

 the sporocysts. The oocyst wall is very thin and all the 

 developmental stages are passed mthin the tissues of the host. 

 The sporocysts fall into the bile ducts and pass out through 

 the ahmentary canal. 



Habitat. — Gall-bladder and bile-ducts of the tortoise, 

 Lissemys punctata granosa (Schoepff) : India. 



116. Eimeria mitraria (Laveran & Mesnil). (Fig. 90.) 



■\Coccidium mitrarium, Laveran & Mesnil, 1902, p. 613, figs. 12-14. 

 Eimeria mitraria, Wenyon, 1926, p. 859, 860, fig. 369, 3-5; 

 Reichenow, 1929, p. 949. 



Schizonts produce twenty fusiform merozoites with a central 

 nucleus. The microgametocytes produce a number of hair- 

 like microgametes. The oocysts have a characteristic mitre- 

 like form, the surface of which, unlike those of other Coccidia, 



Fig. 90.— Eimeria mitraria (Lav. & Mes.). A, oocyst with four spore- 

 blasts ; B, oocyst containing four sporocysts, each with 

 two sporozoites and a residue. (After Laveran and Mesnil.) 



presents four or five ornamental projections. One pole of the 

 oocyst always bears a single projection, and the other pole, 

 which is truncated at the base, bears three (or four) projections 

 round it. The protoplasm retracts itself from the wall of the 

 oocyst, becomes spherical, and divides into four sporoblasts 

 without leaving any cystic residue. Each sporoblast gives 

 rise to an ovoid sporocyst containing two sporozoites and a 

 sporal residue. 



Dimensions. — Schizonts 10-12 jx ; merozoites 3-5 jj, in length ; 

 microgametocytes 10-15 ju, in diameter ; oocysts 10-15 /x in 

 diameter. 



