SEXUAL PHENOMENA IN THE PROTOZOA 



231 



gametes and microgametes occurs during the same day, and after a 

 similar period of asexual increase, showing that the same ultimate 

 causes probably operate in each. The macrogamete is distinguished 

 from the schizonts by the possession of a reserve store of nutriment, 



Fig. 128. — Life-history of a Coccidium, [SCHAUD1NN.] 

 a, b, c, schizonts and asexual reproduction (schizogony). The merozoites at c repeat the cycle 

 or pass on to the follnwing stages: d, e,f, development of the female or macrogamete; h, i,j, 

 development of the male gametes; ^.copulation; k and /, stages in the formation of the spores 

 and ^porozoites. 



in the form of granules, which are used in the later development. 

 The storage of these granules begins in the young merozoite (Fig. 

 128, e-g) and in the close vicinity of the nucleus. 1 The nucleus is 

 not essentially different from that of the schizont, but at one stage, 

 according to Schaudinn, a large amount of chromatin is thrown out of 



1 Cf. yolk-formation in eggs of Metazoa ; see Wilson, The Cell, p. 155. 



