Blood of Australian Animals. 189 



low as 6/y. x (i/jL. As these latter observers point out, the Teleostei 

 have evidently branched off from the main stem, giving rise to 

 liatrachians and reptiles, so that there is little of comparative 

 interest in this reading. 



Batrachia. (Plate XVIII. ; Figs. 7-17.) 



Red Corpuscles. — Considerable variations in the size of all types 

 of eell were observable in this group; but, with the doubtful excep- 

 tioi) of one slide from a tadpole, the young forms have larger eor- 

 puscles than the adult. Spindle cells were found in Lymnody- 

 nastes dorsalis, averaging 2'6fi x 12.45//, also in fresh blood 

 of lhil<i aurea, used for laboratory demonstration purposes, and 

 in the haemocytometer ; while in the majority of cases baso- 

 phil polychromatic reds were found. Some of these stained more 

 deeply than others, and, witli the exception of L. dorsalis, averaged 

 smaller than the ordinary red. The chromatin of these forms 

 did not stain as deeply as that of the typical erythrocytes. The 

 smears also contained masses of a homogeneously staining sub- 

 stance, or. in other cases free nuclei (cf. Fantham (5) p. 728); 

 while in one young //. aurea were forms with vacuolated protoplasm, 

 and very densely stained nucleus. In some eases the red cells 

 were apparently in a state of active division. This Avas observed 

 chiefly in /.. dorsalis. Gruner (p. 94) remarks seven varieties of 

 red cell in the frog, giving their average size as 14.5 x 25 /x, and 

 their number as half a million per c.cm, being much fewer than 

 in other animals. 



Lymphocytes varied much in size and shape, ranging from 

 6.6/x to 1 3.4/i. x 5.3//.: and were occasionally, e.g., H. aurea and 

 L. dorsalis, observed with the nucleus in a state of division. In 

 L. dorsalis they showed a distinctly fringed outline, comparable 

 to that described by Erhlich in human blood. They were always 

 basophil. 



Mononuclear forms were strongly basophil, and varied much 

 in size, and also in relative numbers, showing all gradations from 

 8.6/x-19.9/x in diameter [cf. description of intermediate forms by 

 Stephens and Christopher (9), p. 19], the average size falling, 

 however, between 10 /a and 14//.. The nucleus tended to become 

 segmented, and the cell substance to contain granules. 



Eosinophils were not, as a rule, clearly defined, with the excep- 

 tion of L. dorsalis and //. peronii, in which there was a decided in- 

 crease in the relative numbers of these cells, together with a 

 marked difference in the size of the granules as compared with 



