100 T. H. JOHNSTON AND J. B. CLELAND. 



parasites found in warm blooded animals, even if not 

 generically distinct from these. Summed up, in fact, on 

 the material and descriptions before us, we are unable to 

 draw any sharp distinction between the two genera Plas- 

 modium and Haemocystidium, except that of the nature of 

 the hosts. Minchin 1 seems to have experienced the same 

 difficulty when classifying Haemocystidium as a synonym 

 under Plasmodium. 



Description of the Parasite.— Nearly all the forms met 

 with were more or less rounded, and, we believe, represent 

 the gametocyte stage. They correspond to the spherical 

 male and female bodies described by Oastellani and Willey, 

 whose larger oval bodies on the other hand perhaps repre- 

 sent nearly mature schizonts. The only departure from 

 the rounded shape that we encountered, save in immature 

 forms, were occasional kidney-shaped parasites, and in one 

 case an imperfect halteridium shape lying along the side of 

 the corpuscle and slightly embracing the nucleus. With 

 this exception, all the bodies occupied the end of the cor- 

 puscle, the shape of which was not distorted nor was the 

 nucleus displaced in any instance. Immature forms were 

 very few, and always half-grown, and showed a slightly 

 irregular rounded contour with several short amoeba-like 

 prolongations. Such prolongations were also seen in one 

 nearly mature rounded form. 



In some of the rounded bodies, the protoplasm was very 

 faintly stained with very few granules : in others much 

 more deeply coloured with scattered fine granules, some- 

 times with the circumference of the parasite clearly out- 

 lined by a deeper stained narrow zone. Intermediate 

 stages between these two were met with, however, and 

 vacuoles, one, usually two, occasionally several, were 

 found in both very pale and deeply stained parasites, whilst 



1 Albutt and Eolleston's System. Med., Vol. n, part ii, p. 74. 



