JAWS AND TEETH OF ROTIFERA. 6^ 



animalcule seizes and tears to pieces its living prey; 

 for the Rotifera possessing this dental apparatus are 

 carnivorous, and very rapacious. Others have several 

 teeth fixed at the moveable extremity of each jaw, 

 forming, as it were, toothed hammers, which strike 

 upon a solid body, the food being thus comminuted, or 

 crushed, as upon an anvil {Brachionus, pi. xii, 1, 2, 

 and lign. 5, fig. 2). 



LiGN. 5. — Fig. 1, Jaws and Teeth of the Floscularia, highly magnified. 

 Fig. 2. Jaws and Teeth of the Brachionus. 



In some species each jaw is of the shape of an open 

 stirrup, and the two are placed horizontally, the trans- 

 verse bars being opposed to each other. The teeth lie 

 across the arch, and are fixed by one end to the upper 

 transverse process; the lower process gives support to 

 the muscles. This structure is well exemplified in the 



