762 



PATHOGENIC PROTOZOA 



ookinetes, zygotes and oocysts in the lower portion of the midgut. As 

 the ob'cyst grows, it stands out from the gut wall and finally shows the 

 striations indicative of the presence of sporozoites; after rupture of 



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FIG. 180. H^MOPEOTEUS COLUMB^E. la to 3a, Development of female parasite in 

 blood of dove; Ib to 3b, Development of male parasite in blood of dove; 4a, 4b, 

 5b, 6 to 12, Development in the digestive tube of the fly (Lynchia) ; 13 to 20, 

 Development of the parasite inside leucocytes in the lung of the dove. (After 

 Avagao. MacNeal, "Pathogenic Microorganisms," published by P. Blakiston's 

 Sons & Co.) 



