436 



SPECIFIC MICRO-ORGANISMS 



is unknown, but it may be due to the mechanical streaming of the 

 blood acting upon the bladder-like cell which has been deprived of 

 elasticity by the destructive action of the parasite. The further 

 stages in the cycle of sporogony are unknown. An asexual 

 multiplication probably occurs in some internal organs of the bird. 

 Fantham has observed schizogony in ] the spleen of Lagopus 

 scoticus, the red-game grouse of Scotland, infected with a similar 

 parasite Leukocytozoon iovati. 



Fig. 195. — Diagram of the developmental cycle of Proteosoma. i. Sporozoit 

 entering an erythrocyte; 1, 2, 3 and 4, the cycle of schizogony; 5, macrogameto- 

 cyte; Sa, microgametocyte; 6, macrogamete; 6a, formation of microgametes; 7- 

 fertilization; 8, ookinete; 9, formation of sporoblasts (in mosquito); 10, forma- 

 tion of sporozoits; 11, sporozoit. (From Doflein after Schdudinn.) 



Proteosoma (Plasmodium) Praecox. — Grassi and Feletti de- 

 scribed this malarial parasite of birds and designated it as Ham- 

 amoeba prmcox} The parasite is very common in the blood of 

 small birds, such as sparrows, robins and larks, in all parts of the 

 world. The cycle of schizogony is completed in the peripheral 

 circulation. The small merozoit or agamete enters an erythro- 



1 Centrabl.f. Bakt., 1891, Bd. IX, S. 407. 



