AGGREGATA. 



201 



Fig. 99. — Life-cycle of Aggregata eherthi Labbe. The stages above 

 the dotted line occur in the cuttlefish, those below in the 

 crab. R, merozoite swallowed by the cuttlefish ; A, un- 

 differentiated parasite in submucous tissue ; B, C, D, growth 

 into niicrogametoe3rte and production of microgametes ; 

 E, F, G, growth into macrogamecyte and fertilization ; 

 H, zygote ; /, first nuclear division in zygote ; J, K, nuclear 

 multiplication in zygote and production of sporoblasts ; 

 L, sporocyst containing three sporozoites and small residual 

 body ; M, escape of sporozoites in intestine of crab ; N-Q, 

 growth of schizont and production of merozoites in sub- 

 epithelial connective tissue. (From Wenyon, after DobeU.) 



