PHYLUM PROTOZOA 



91 



protoplasm, while the outer portion is tolerably firm and resistant. 

 When partially retracted, a spiral ridge is sometimes observable 



\ 



C.VGO 



7.0t>hryodendron 



S.Epholol-a 



FIG. fi7. Various forms of Tentaculifera. la and h, two species of PodopJirva: c, a 

 tentacle much enlarged ; 2a, Acineta jolyi ; 2!>, A. tuberosa ; in 6 the animal has captured 

 several small Ciliata ; 8a, a specimen multiplying by budding ; ,V6, a free ciliated l>ud ; 9a, the 

 entire colony ; .%, a portion of the stem ; 9c, a liberated bud ; a, organism captured as food ; 

 b.c. brood-cavity ; >><(. bud ; c roc. contractile vacuole ; my. nu. meganucleus ; mi. nu. micro- 

 nucleus ; t. tentacle. (After Butschli and Saville Kent.) 



around the tentacle : this may indicate the presence of a band of 

 specially contractile protoplasm, resembling the axial fibre in the 



