[Proc. Eoy. Soc. Victoria, 23 (N.S.), Pt. I., 1910.] 



Art. VIII. — Note on a Haemogregarine in the Blood of 

 Varanus varius. 



By J. A. GILRUTH, D.V.Sc, M.R.C.V.S., F.R.S.E. 



(Professoi' of Veterinary Pathology in the University of Melbourne) 



(With Plate VI.). 

 [Eead 26th May, 1910.] 



Protozoa have been described as occurring in the blood of 

 nearly all animals, generally associated with a diseased condi- 

 tion of the host (as Malaria and Sleeping Sickness in man, and 

 Tick Fever in cattle), but not necessarily so, for the common rat 

 is often found to harbour a trypanosome which seldom, if ever, 

 produces any deleterious effects. 



In many members of the Reptilia, especially the snakes, a 

 falciform protozoan parasite has been discovered affecting the 

 red cells of the blood. These parasites, in whatever species of 

 cold-blooded vertebrate, are found to bear so close a resemblance 

 to each other in general characteristics that, although by some 

 considered to belong to one or other of three genera (Lankes- 

 terella, Karyolysus, and Haemogregarina), they are now usually 

 placed in the one genus Haemogregarina of the family Haemo- 

 gregarinidae of the group Sporozoa. 



In Australia the presence of the genus Haemogregarina has 

 been recorded in the blood of the Diamond Snake (Python 

 spilotes Lacep), the Native Cat (Dasyurus viverrinus Shaw), 

 in a Marsupial Squirrel {Petaurus sciurus Shaw), and in the 

 Northern Carpet Snake {Python amythestinus Shaw), amongst 

 native fauna, and also in the common rat (Mus decmnanus) 

 both in Sydney and Western Australia.^ So far as I can find 

 Haemogregarines have not been described in Australian lizai-ds, 

 though they have been elsewhere observed in species of Varanus, 

 including one {H. borreli) from Varanus griseAis described by 



1 See Pro. Linn. Soc. N.S.W., 1909, p. 400 et seq. On some " Haemogregarines from 

 Australian reptiles," by T. Ilarvej' Johnston. 



