28 MALARIA 



apparently no development in low temperatures (ac- 

 cording to Manson this phase of the malaria parasite 

 requires a "sustained average temperature of at least 

 6o° F."). Thus it will be seen very readily that the 

 time factor plays an important role in the transmission 

 of malaria. 



Is Malaria inherited by Mosquitoes ? — For the 

 reason that malaria is said at times to be contracted 

 by explorers who have entered uninhabited territory, 

 it is believed by some that the mosquitoes of the said 

 territory had become infected perhaps years ago and 

 that the parasite has been handed down from genera- 

 tion to generation from the female to the ovum, ovum 

 to larva, and thus through the mosquito cycle. The 

 fact that Texas cattle fever is thus inherited and in- 

 fection is secured through the young seed tick seems 

 to lend some weight to the argument. Explorers and 

 others who have malaria in uninhabited regions have 

 pretty surely become infected before entering such 

 territory, and the disease is merely brought on by 

 fatigue or even in due time after infection, correspond- 

 ing to the incubation period. 



Knowing the life history of the parasite, it would 

 be more reasonable to suspect that other warm-blooded 

 animals besides man may harbor the protozoan during 

 its asexual cycle, a matter not, however, as yet proved. 



Furthermore, specimens of Anopheles maculipennis 

 larvae were transported by the writer from an intensely 

 malarial district to Berkeley and the adults reared from 



