BY T. H. JOHNSTON AND J. B. CLELAND. 483 



mentioned, the presence of three different types of haematozoa, 

 including the above haemogregarine. The other film was 

 negative. Films taken from the same species in September 

 and in October, 1910, in the Burnett River, by Dr. Bancroft, 

 were forwarded to us ; and, on examination, the former was 

 found to contain Trypanosoma chelodina, as well as the above 

 hsemogregarine, whereas in those of the latter date, only a 

 few hcemosporidia were detected. The same parasite was 

 found in films taken from a long-necked tortoise, Chelodina 

 longicollis, by the same gentleman (Burnett River). We have 

 also recognised as belonging to the same species, the hsemo- 

 gregarines present in films taken from this tortoise by Dr. 

 Angas Johnson (Murray River, South Australia). The latter 

 films also contained the trypanosome described by him (1907, 

 p. 26) as Trypanosoma chelodina, and were forwarded to Dr. 

 H. G. Chapman, who kindly allowed us to compare our try- 

 panosomes with those present on this slide. 



The hasmogregarines were variable in size, those from the 

 Chelodina longicollis from Queensland being small, averaging 

 about 10xr)-3/^. The longest forms detected, were found 

 in the same species from the Murray River, some reaching 

 17/x in lengtli x 6 /x in bi'eadth. The broadest parasite .seen 

 by us, was found in Chelodina oblonga, and measured 16-5/x 

 in length by 7-8 /x in breadth. The smallest and youngest 

 form noticed, was only 5 //, long and under 1 /x in ma.ximum 

 breadth. It was club-like, one end being narrow and tapering, 

 the other broad and rounded. It was seen in Chelodina longi 

 collis. 



The general form of the hsemogregarine was elliptical or 

 reniform, possessing a fairly regular outline. In such cases, 

 the ends were alike, though the nucleus usually approximated 

 towards one extremity, the posterior. In a few parasites, a 

 well-marked "tail" was present, lying bent round so as to be 

 parallel to the main part of the "body." 



The protoplasm became stained a pale blue on using 

 Giemas's stain, there being an appearance of vacuolatioii in 



43 



