120 SPOROZOA. 



Intra-corpuscular individuals of various forms and sizes, 

 many of them showing a characteristic pink-staining sheath. 

 Free gregariniform individuals actively motile in the blood 

 plasma. Small forms enter by boring directly into the cor- 

 puscle. Occasionally the organism, on reaching the inside 

 of the corpuscle, rests for a few minutes and then wriggles out 

 again into the plasma. 



Dimensions. — Length 26-28 /u, ; mdth 4-5- 5 /x. 



Fig. 46. — Heemogregarina berestneffi Cast. & Will. A, intra-corpuscular 

 form ; B, free form. (After Dobell.) 



Remarhs. — ^According to Berestneff the parasite lies within 

 a strongly refringent colourless capsule, both ends of which 

 are rounded and curved, the whole embracing the displaced 

 nucleus of the corpuscle after the manner of a Halteridium ; 

 it shows a very close resemblance to H. magna, found in the 

 same hosts, but differs by the possession of a capsule. The 

 parasite was named H. berestneffi by Castellani & Willey 

 (1905), who, however, did not find the parasite in hosts of the 

 same species from Ceylon. Dobell (1910) found the species 

 in Hana tigrina from Ceylon. Patton (1908, p. 319) notes 

 that he had the opportunity of studjang no less than five 

 Hsemogregarines in E. tigrina and R. hexadactyla and also in 

 the leech which transmits them, but he does not mention the 

 species encountered. Wenyon (1926, p. 1398) records H. en- 

 cajpsulse Berestneff as a parasite of R. limnocharis and both 

 H. encajpsulse Berestneff and H. berestneffi Castellani & Willey 

 from R. tigrina. The name H. encapsulse Berestneff is an 

 error, as Berestneff did not give this name to his form, and 

 so it must be treated as a synonym. 



Habitat. — Blood of Rana tigrina Daud. and R. limnocharis 

 Wiegmann : Bombay, Bombay ; Rana tigrina Daud. : Ceylon, 

 Colombo ; R. tigrina Daud. and R. hexadactyla Lesson, and 

 in the leech which transmits them : Madras, Madras ; 

 R. tigrina Daud. : PoRTUorESE India, Nova Goa ; also 

 R. tigrina Daud. from India, in the Zoological Gardens, 

 London. 



