230 



ANIMAL PARASITES 



quito. When a mosquito bites a human being they are introduced 

 into the blood where they are quickly transformed into the intracellu- 

 lar hyaline bodies and begin their asexual sporogony in the blood. 

 Each developmental cycle causing a febrile paroxysm either every 

 day or alternate days, or on every fourth day, etc., depending on the 



FIG. 83. Coccidium hominis, fron intestine of rabbit: i, a degenerate epi- 

 thelial cell containing two coccidia; 2, free coccidium from intestinal contents; 

 3, coccidium with four spores and residual substances; 4, an isolated spore; 5, 

 spore showing the two falciform bodies Xii4o. (From Railliet, in Tyson's 

 Practice.) 



character of the organisms and the number of infections. To pre- 

 vent spread of malaria, mosquitoes must be prevented from reach- 

 ing individuals infected with malaria and those not infected. Screens 

 accomplish this best. The larva of the mosquito develops in stag- 

 nant water. To prevent the development of these young mosqui- 



