ZOOLOGY 



In some cases the conjugating cells are of two sizes, union always 

 taking place between a large cell or megagamete and a small cell 



nu c.vac 



Fia. 57. — Heteromita rostrata. A, the positions assumed in the springing movements 

 of the anchored form ; B, longitudinal fission of anchored form ; C, transverse fission of 

 the same ; U, fission of free-swimming form ; B, conjugation of free-swimming with anchored 

 form ; E 5 , zygote ; E<>, emission of spores from zygote ; F, development of spores ; fl.l, ante- 

 rior ; fl.S, ventral flagellum. (From Parker's Biology, after Dallinger.) 



or microgametc. In Vol vox (Fig. 56) this dimorphism reaches its 

 extreme, producing a condition of things closely resembling what 



