CLASSIFICATION OF CTENOPHORES. 



95 



Order 2. Saccatce. Body more or less spherical, with two long tenta- 

 cles capable of being wholly retracted in a sac (Pleuro- 

 brachia). 



Order 3. T&niata. Body ribbon-like, being very much compressed in 

 the direction of the lateral diameter (Cestum). 



Order 4. Lobatce. Body lateral, compressed, bilobed (Bolina). 



VIEW OF THE CLASSIFICATION OF THE CTENOPHOKA. 



Lobata. 

 (Boliua.) 



T&niata. 

 (Cestum.) 



Saccata. 



(Pleurobrachia.) 



Eurystomeas. 

 (Idyia.) 



CTENOPHOKA. 



Laboratory Work. The Ctenophorse should be studied while alive. 

 They may be collected with a drag or tow-net from a boat when the 

 surface of the ocean is calm. For studying the fine anatomy and 

 tissues they should be treated by the same methods as the smaller jelly- 

 fishes. 



' '> It A /; 



