THE ANIMAL KINGDOM 



379 



a macrogamete, with which it fuses to form the zygote. The 

 zygote in the course of 24 hours is transformed into an active 



Some may be taken 

 into the stomach 

 of the Ulosquito when 

 it bites 



luman 



Development of 

 Parasite in 



6 



InSalivary Development 

 -n Gland 

 f\ offflosq. 



in the 



\ 



\ J /^ Body 



my Cavit y°f m ° sc i 

 i/ 



mosquito 



><» 





'•RARy 





Fiu. 212. — Diagram illustrating the life history of malarial parasite. 1, 

 red blood corpuscle; 2 to 7, schizogony; o, 6, c, a', b' , c' , development of gameto- 

 cytes; d, zygote; e, ookinete; /, g, h, development of oocyst; i, liberation of 

 sporozoites; k, section of salivary gland. (From Doane, Insects and Disease, 

 Henry Holt & Company. By permission.) 



ookinete, which bores into the stomach wall, in the outer 

 layers of which it forms the oocyst. The latter grows in size 

 and then divides to form sporoblasts, each of which, in turn, 



