Orders 

 CYDIPPIDA 



(Two tentacles, retractile into 

 sheaths) 



LOBATA 



(Numerous lateral tentacles 

 contained in a groove ; body 

 compressed ; two large oral 

 lobes) 



CESTIDA 



(Ribbon-like form, from body 

 being extremely compressed 

 in the vertical plane) 



BEBOIDA 



(No tentacles; mouth very 

 wide ; gullet occupies greater 

 part of body) 



Class 

 CTENOPHORA 



Genera 



< Pleurobrachia 



<| Bolina 



' Mnemiopsis 



< Cesium 



Idyia 



Species 

 P. rhododactyla 



B. alata 



B. septentrionalis 



B. vitrea 

 M. Leidyii 



C. veneris 



I. roseola 

 I. cyanthina 



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