PROTOZOA IN THE CIRCULATORY SYSTEiM 95 



2. Growth period. The infected erythrocytes are more 

 or less oval with irregular fimbriated margins or outline 

 (Fig. 25, 2-4). There seems to be a slight increase in size 

 also. The schizonts are not actively amoeboid, and some- 

 times seen in band form with brownish -black haemozoin 



•«|^' 



Fig. 25. Plasmodium ovale. X 1150. (original) 



1. A ring fomi. 



2, 3. Growing schizonts. 

 4-6. Schizogonic stages. 



7. A macrogametocyte. 



8. A microgametocyte. 



granules, resembling those of P. malariae. Schiiffner's dots 

 are usually abundant. 



3. Schizogonic stage. The fully grown schizont is smaller 

 than the erythrocyte (Fig. 25, 5), and produces 6-12 mero- 

 zoites (Fig. 25, ^), which resemble those of P. malariae. 

 Schiiffner's dots appear abundantly. 



Gametocytes 



The gametocytes do not fill the erythrocytes, and re- 

 semble closely those of P. malariae. But in P. ovale, the 

 host cells show Schiiffner's dots and seem to be slightly 

 enlarged (Fig. 25, "'^ ^). 



