THE SPOROZOA 



163 



nikoff, Manson, and others regarded it as an essential develop- 

 mental stage of the malaria organism, and believed that the free- 



Fig. 90. Life-history of Malaria, causing Sporozoa. [Ross and FiELDlNG-OULD.] 

 A-F. Stages in the development of merozoites. A- 1. The sporozoite. B, C, D, and jf, K, L. 

 The growing sporozoite in blood-corpuscles. . Asexual reproduction (schizogony). f, G, and 

 M. Liberation of merozoites and melanin granules. O- W. Stages in the development of sexual 

 individuals. R. Polymitus form. S. Fully developed microgametes. T- W. Development of the 

 female individual (macrogamete). X. Fertilization of a macrogamete by a microgamete. Y. The 

 fertilized cell copula, with its vitelline membrane, a-e. The copula in the stomach of the mosquito 

 {Anopheles sp.). b. The copula penetrating the epithelium which lines the stomach of Anopheles, 

 b, c, d, e. Growth of the copula in the body-cavity of Anopheles. The small spheerules at V, W, and 

 X are supposed to be analogous to polar bodies of metazoan eggs. f. Sporulation in the body- 

 cavity of Anopheles, g. Liberation of the sporozoites. h. Salivary gland (in section) , with sporo- 

 zoites in the lumen, in the cells, and penetrating the membrane. 



swimming detached processes are germs which reproduce the adult. 

 Many others (Grassi, Felletti, Celli, Sanfelice, Sacharoff, Labbe, etc.), 

 however, regarded these forms as degenerating parasites induced 

 by the abnormal conditions of exposure and not present, normally, in 



