OF CONCHOLOGY. 



turcs two, generally placed near the 

 upper end, one beneath the other. 



8th. TETHYS. 

 Body detached, rather oblong, 

 fleshy without peduncles ; mouth with 

 a terminal cylindrical proboscis, under 

 an expanded membrane or lip; aper- 

 tures two, on the left side of the neck. 



9th. TRITON. 

 Body oblong ; mouth with an invo- 

 lute spiral proboscis ; tentacula, or 

 arms, twelve, six on each side, divided 

 nearly to the base, the hind-ones che- 

 hferous. 



10th. SEPIA. 

 Body fleshy, receiving the breast in 

 a sheath, with a tubular aperture at 

 its base ; arms eight, beset with nu- 

 merous warts or suckers, and in most 

 species two pedunculated tentacula ; 

 Iiead short ; eyes large ; mouth re- 

 sembling a Parrot's beak. 



