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MOLLUSGA— SYSTEMATIC REVIEW 



83 



Fig. 33.— Spirilla prototypos, right aspect (after Cbun and Owen), 

 from Leuckart and Nitsclie, Zool. Wandtafuln. Both portions of the 

 shell are visiblej the inner portion seen through the mantle. The eye 

 should he placed more anteriorly on the " head" (Kopflfuss). 



^ 



B 



Fio, 34.— LoligO vulgaris (after D'Orbigny). A, Dorsal (physiologically ventral) view; B, 

 anterior (physiologically dorsal) view. Of the five pairs of anns, the fourth are seen to be 

 developed as long prehensile tentacles ; the eyes, the edge of the mantle, the fins, and the 

 chromatophores in the skin are depicted. 



