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A MANUAL OF BACTERIOLOGY 



and accumulate in the salivary or poison glands, whence 

 they are discharged by the middle stylet (hypopharynx) 

 of the proboscis, when the insect " bites," into the circula- 

 tion of a fresh vertebrate host. Here, presumably, the 



Human Phas'e 



Endogenous 

 or Asexual Cycle 



The 

 Mosquito Phase 



Exogenous 

 or Sexual Cycle 



FIG. 60. Diagram of the asexual and sexual cycle of the malaria 

 parasite. 



blasts become attached to erythrocytes and develop into 

 amrebulse. The diagram x (Fig. 60) represents in graphic 

 form the asexual and sexual cycles of reproduction of the 

 malaria parasite. 



So far as is known, malarial infection is conveyed 

 only through the bite of infected mosquitoes of the 



1 This figure is reproduced by permission from Daniel's Laboratory Studies 

 in Tropical Medicine (Bale, Sons, and Danielsson, 1908). 



