A NEW MELANIN-PRODUCING HAEMATOZOON. 97 



On a new MELANIN-PRODUOING HAEMATOZOON 

 from an AUSTRALIAN TORTOISE. 



By T. Harvey Johnston, ma., b. sc, Assistant Microbi- 

 ologist, and J. Burton Oleland, m.d., ch.M., Principal 

 Assistant Microbiologist. 

 (From the Bureau of Microbiology, Sydney, N.S.W.) 



[With Diagram I and Plate III.] 



[Bead before the Royal Society of N. S. Wales, July 7, 1909.'] 



During the examination of the blood of a specimen of the 

 common Australian tortoise, Chelodinalongicollis, captured 

 near Sydney in April 1909, a number of pigmented parasites 

 of the red cells was met with. The characteristics of 

 these protozoa were a more or less regular spherical shape, 

 occasionally in the younger stage with short amoeba-like 

 projections, sometimes in the older stage with a kidney- 

 shaped indentation, the site occupied being almost always 

 the end of the corpuscle, very rarely the side ; the non- 

 displacement of the nucleus and the absence of any distor- 

 tion of the host cell ; the presence of masses of melanin 

 pigment, and the presence of two (sometimes one, occas- 

 ionally several or more) vacuoles. 



On searching the literature at our disposal, we could 

 only find two references to melanin producing haematozoa 

 of reptiles, one, Haemamoeba metchnikovi described by 

 Simond from a tortoise, Trionyx indicus, 1 and the other, 

 Haemocystidium Simondi taken from a gecko, Hemidacty- 

 lus leschenaultii, in Oeylon, and described by Oastellani 

 and Willey, 2 who made it the type of a new genus Haemo- 

 cystidium, 



1 Simond, Ann. Inst. Past., 1901' p. 319. 

 ■ Spolia Zeylanica, Vol. n, pt. 6, August 1904, p. 84. 



G— July 7, 1909. 



