MALARIA AND MOSQUITOES 



93 



FIG. 21 STAGES OF PLASMODIUM VIVAX IN THE STOMACH OF THE 

 MOSQUITO, SHOWING FORMATION OF GAMETES AND FERTIL- 

 IZATION 



A , The young gametocyte within the blood-corpuscle ; B, $ , micro- 

 gametocyte; B } ? , macrogametocyte ; C, <$, microgametocyte 

 with nucleus divided into several parts ; C, $ , older macro- 

 gametocyte ; D, $ , microgametocyte giving off microgametes 

 (a free male is near) ; D, . , macrogamete giving off a small part 

 of its nuclear material prior to being fertilized ; E t fertilization ; 

 F, zygote or ookinete which has become slightly elongated and 

 is capable of free movement. [There should be more diffuse 

 chromatin in D, $ ] 



