60 



INFUSORIA. 



or embryos, either of higher animals or true hi' 

 fusoria. 



5. Form and §4ruetiire, — In outward form 

 the Infusoria may be said to vary indefinitely, all 

 being, however, more or less rounded (figs. 13 and 

 14). The presence of a simple spu'ally contrac- 

 tile stalk is especially characteristic of the true 



Fig. 13. 



Various forms of Infusoria : — a, Stentor Miilleii ; b, Chi- 

 lodon cucullulus; c, Oxytricha gihba ; d, Aspidisca lynceus; e, 

 Euplotes patella (under view) ; e', the same (side view) ; /, Pe- 

 ranerna globulosa ; g, Vaginicola crystallina. 



Vorticellce ; in other stalked forms, the pedicle is 

 either rigid as in Epistylis, or branched as in 

 CarchesiiiTii and Zoothamoihion, Vaginicola (fig. 

 13, g) has the body protected by a membranous or 



