PLATE I 



PLATE I 



LIFE-CYCLE OF THE TERTIAN MALARIAL ORGANISM, Plasmodium 



vivax 



The stages above the dotted line occur in the peripheral blood of 

 man, whereas those below are found only in the mosquito. 



1. Sporozoite. 2. Trophozoite, in red cell. 3. Full-grown schi- 

 zont. 4. Schizont with chromatin in several masses. 5. Seg- 

 mentation stage. 6a. Male gametocyte. 6b. Female gametocyte. 

 7a. Exflagellation of male gametocyte formation of microgametes. 

 7b. Female gametocyte extruding chromatin from nucleus. 8. 

 Fertilization of macrogamete by microgamete. 9. Ookinete. 10. 

 Young oocyst. 11. Oocyst with sporoblasts forming. 12. Ripe 

 oocyst discharging sporozoites. 



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