Blood <>/ Australian Animals. 193 



these cells were first observed, they averaged slightly smaller than 

 the ordinary erythrocytes, with rounder nuclei. The smaller cells 

 tended to be basophil, the larger staining normally. Normal baso- 

 phil cells were also common, their nuclei being larger, and taking 

 the stain less darkly than the ordinary forms, and showing a 

 great tendency to branch or bud ; in fact, in T . rugosus one was 

 observed showing three nuclear masses. 



Lymphocytes varied in size, the largest being found in young 

 Gramat. muricata. These were distinctly oval in shape, measuring 

 1 1.9//. x 6.6/x. On the other hand those of young Tiliqua scin- 

 coides ran smaller than any other form, viz., 4.8/j.. The percent- 

 age counts also varied, being fairly high in young individuals. 

 The fringe of ragged protoplasm observed in some batrachia was 

 also seen in this group (Track, rugosus and Til. nigra-lutea). In 

 the former these cells were most distinct when treated with .Tenner's 

 stain, and an appearance was obtained resembling division. The 

 general shape varies from oval in Gram, muricata to round in 

 Track, rugosus, while in other cases it Avas almost impossible to 

 distinguish lymphocytes from free nuclei. 



Mast cells were common in this group, averaging larger than 

 the mononuclear forms, but they were not present to any large 

 percentage. The greatest number was found in the young of 

 Gram, barbata, where they were present to the extent of 13.8 per 

 •cent, of the total white cells. They were common in Ckel. longicollis, 

 in which, as in Track, rugosus, they showed both large and small 

 varieties. In Track, rugosus also, one was seen apparently in a 

 state of division, and in this species the granules of the corpuscle 

 were distinctly divided into large and small ; while some cells 

 appeared transitional in staining between the mononuclear and the 

 mast variety, staining more darkly purple than the ordinary mono- 

 nuclear forms, and with a few characteristic granules in the proto- 

 plasm. 



Transitional forms of ordinary type were not observed. 



Mononuclear cells varied in size, and might be divided into two 

 classes — (a) Small, ranging from T.9//.-9.9//. ; (b) those correspond- 

 ing more nearly to those of other forms, and ranging from 11.7/t- 

 15.4//., while in the carpet snake (specimen in very pathological 

 condition) they ran up as high as21.1//.. 



The percentage counts were fairly high, but it was difficult in 

 many cases to make a rigid distinction between large specimens of 

 class (a) and small specimens of class (b). The small forms of Ckel. 

 longicollis were distinguished from the lymphocytes by the presence 



