GENERAL CLASSIFICATION 



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Conchs. 



Order 2. — Cephalic Molluscs. 



A distinct head and eyes, and two or four tentacles in the majority, jawa or a 

 proboscis at the mouth ; reproduction by copulation. 



The shell of those, which have one, never consists of two valves articulated at a 

 hinge. 



(1) Pteropods. 

 Two opposite, swimming fins. 



Hyalea. 



Clio. 



Pneumoderma. 



(2) Gastropods. 



(A) Straight body, united to the foot throughout the whole or nearly the 

 whole of its length. 



Tritonians. 



Glaucus. 



Aeolis. 



Scyllaea. 



Tritonia. 



Tethys. 



Doris. 



