62 



in grains around its nucleus. Feeding on the blood cor- 

 puscle, it now almost fills it. It is now ripe ior reproduc- 

 tion, asexual by schizogony ; the nucleus divides up, 

 and the protoplasm is segmented. The result is a number 

 of nucleated merozoites around a small portion of residual 

 protoplasm, where all the melanin has accumulated. This 

 is the rosette stage. The blood corpuscle now breaks up, 

 the merozoites are set free in the blood plasma, and the 

 melanin is scattered. This completes the Schizogony cycle. 



KEY TO FIG. 13. 



A combined diagram (the figures are not all from the same species). 

 Figures akdrS the dotted line represent stages passed in human 



blood ; those below are stages found in the mosquito. 

 r to V. and 6 to 10, Schizogony of tertian parasite, Plasmodium 

 vivax After Schaudinn, and magnified about 1500 diameters. 

 WT Vila., and Vllb. Formation of gametocytes of pernicious 



' > ar i'a (Plasmodium falciparum). 



TW* XIIL Stages of sexual generation of Plasmodium vivax 

 Vim. to * 4h of mosquito. After Schaudinn. The sign $ signifies 



ma!f m p female ' 

 XIV. .to XVm. " Sporogony. Diagrammatic. 



r\ lorozoites. 



Germs or S 



IV. ': Signet-ring'- 

 V. Amoeboid tropho. meroz oites. 

 9. Rosette stag and . 

 10. Free ; mm>zoites. Descent." 



la. Male gametocyte or %. rescent." 

 Tllb. Female- -gametocyte or * c. One is shown free. 



Xa. Formation of microgamet^ rtion of nucleus. 

 Xb. Macrogametocyte extruding po. mete (" sperm ") is shown 

 XL Process of Syngamy. A microga. " ovum "). 



penptrating the macrogamet^ ( side it is a cluster of 



XII. A zygrote which is elongating. Ba. s "). 



degenerating microgametes (' spenu 

 XIIL Motile oukinete. 

 XIV. Oocyst or spore-cyst. 

 XVI. Sporoblasts formed. 



XVII. Formation of sporozoites. i residual 



XVIII. Ripe cyst containing numerouj?i 

 protoplasm 



