208 



THE SCIENCE OF LIFE. 



Olive, Cone, Harp, Murex, (Fig. in,) Whelk, (Fig. 112,) 

 and Winged-shell, (Fig. 113.) 



FlG. 112. The Whelk, (Bitccinuui,) showing its operculum. 



7. CEPHALOPODA, (Gr., cephalc, head ; pous, foot.) The 



class of Cephalopods stands 

 at the head of the Molluscan 

 type. Some of its forms sur- 

 pass in complexity of struct- 

 ure the highest Articulates, 

 although not so representa- 

 tive of their type as the Gas- 

 teropods. They are aquat- 

 ic free-swimming or creeping 

 Mollusks, inclosed in a mus- 

 \LL--y cular mantle, and in some 



. 113. Strombus gigas, or Winged- 

 shell ;" one fifth natural size. West Indies. spCClCS having a Univalve 



shell. The foot is divided into eight or ten long, wav- 

 ing, but strong tentacles, bearing numerous suckers, or 



