1102 PROF. E. A. MINCIIIN ON [Dec. 10^ 



and D and that seen in slides A and B already described ; I 

 think my figures show this point with sufficient clearness. 



Besides the slender elongated forms just described, there are 

 found also (but less commonly) short, stumpy intra-corpuscular 

 parasites (PI. LVI. figs. 17, 18) — not in the least comparable, 

 however, to the young forms found on slides A and B. They 

 give me the impression, rightly or wrongly, of being dwaifed, 

 stunted forms, which for some reason have not attained their full 

 growth. Their nucleus is as large as, or even larger than, that 

 of the long forms, and has the same type of structure, with the 

 fenestrations even more apparent in many cases ; it occupies 

 at least half, sometimes mvich more than half, the length of the 

 body, leaving two clear poles free from chromatin at either end. 



A third type of intra-corpuscular parasite, found in a few cases 

 (figs. 20, 21), was also stouter than the more elongated forms, and 

 noteworthy for the presence of red-staining granules, apparently 

 chromidia, in the cytoj^lasm outside the nucleus. Since these 

 forms resemble, as Avill be shown, the free vermicules in this 

 feature— and since they f recjuently occui' with reversed curvatures, 

 as seen in the figures — I am inclined to regard these stouter 

 forms as ripe parasites, ready to escape from the blood-corpuscle. 



In one single instance I was so fortunate as to find a doubly- 

 infected blood-corpuscle (fig. 16). The two contained parasites 

 can be seen to be below the normal in size, and one is much 

 smaller than the other ; both, however, show abundance of 

 chromatin in the nucleus, and I am inclined to regard their small 

 size as a result of their being stunted in growth owing to lack of 

 sufficient space or nutriment for their proper development. 



Free vermicules, as already stated, were scarce in these prepara- 

 tions, and I only saw one which might have been one of the long 

 forms, but as it was obscured by overlying blood-corpuscles, I could 

 not be sure of it. One stumpy for'm was also found. All the 

 others seen were of what I should term medium length (figs. 22,. 

 23). Their nucleus was similar to the intra-corpuscular forms, 

 but with a tendency to be more compact. But their most marked 

 feature was the presence in their cytoplasm of distinct red- 

 staining granules, apparently of the nature of chromidia ; in this 

 point they contrast sharply with the vei'micules seen on slides A 

 and B, in which the cytoplasm always appeared free from such 

 granules. 



A count of these two slides, cairied out in the manner already 

 described, gave the following results : — 



