80 J. B. CLELA.ND AND T. H. JOHNSTON. 



19. Protoplasm deepish stained, granular. Melanin as 

 spherical masses, 2 towards one end, 1 towards other, 

 3 opposite nucleus. 



20. Smaller, very little, if any, pigment. Outline of 

 parasite irregular. Evidently an immature form. 



The clear and pale forms probably represent male 

 gametocytes. In two of these, the pigment occurred as 

 rods, in the others as masses. It was aggregated more or 

 less definitely at one end. This arrangement of the pig- 

 ment corresponds with that in the described microgameto- 

 cytes. 1 The deepest stained ones may be, on the other 

 hand, macrogametocytes. In these, there seems a decided 

 tendency for the melanin masses to approach nearer to one 

 end than the other, or to be greater towards one end. The 

 intermediate stained ones, which show a similar arrange- 

 ment of the melanin, are perhaps schizonts. It would 

 appear, however, that all stages are met with as regards 

 depth of staining between the quite clear and the most 

 intensely stained and that overlapping as regards the 

 arrangement of the melanin similarly occurs. The amount 

 of pigment did not seem to vary between the extreme 

 forms. The only difference noticed was that in two of the 

 pale forms, it was rod shaped, while in the others angular. 



In examining other examples of the parasites, vacuoles 

 were seen in two instances, in faintly granular specimens, 

 towards one end (Diagram I, fig. 13). In one, this end was 

 that containing decidedly more pigment than the other. In 

 occasional large forms, no pigment was discernible (Diagram 

 I, fig. 9). The red cells measured 11*5 to 12 x 6/x. Some of 

 the parasites 9 x 2/s 10 x 2/*, 11 x 3/*, 12 x 2*5/s and 

 13 x 2/x. 



1 Minchin's Article ' Sporozoa' in Ray Lancaster's Treatise on Zoology, 

 Part i, 2nd fasic, p. 268. 



