220 POL YZOA. PART III. 



Poljzoa have pedicellarise attached to their stems, either 

 sessile or stalked. Their forms are various : a jointed 

 spine, a pair of pincers, &c. But on the Cellularia they 

 are like a bird's head with a crooked beak, opening very- 

 wide, and attached by a stem. B, fig. 159, represents 

 a highly magnified pedicellaria in the act of seizing 

 another. These bird's head appendages are numerous 



Pig. 159. A, Cellularia ciliata ; B, ' bird's head ' process of Bugula avicularia, highly 

 magnified, seizing another. 



on the Cellularia ciliata, and in constant motion ; the 

 jaws are perpetually snapping little worms, or anything 

 that comes in their way, while the whole head nods 

 rhythmically on its stalk. Two sets of muscles move 

 the jaws ; when open, a pencil of bristles projects beyond 

 them, which is drawn in again when they are closed ; 

 they are supposed to be organs of feeling. The Polyzoa 



