245 MARINE SHELLS 



vated striae, not attaining the edge ; base not con- 

 tracted. 



Length nine-twentieths of an inch. 



Animal — about as long as the shell, and the foot 

 is transversely bifid ; tentacnla somewhat wrinkled, 

 cylindrical, rather smaller towards the tips, which 

 are obtuse or rounded ; eyes placed at the inner base 

 of the tentacula ; rostrum somewhat wrinkled, nearly 

 as long as the tentacula, bilobate before 5 foot, ante- 

 rior segment emarginate behind, posterior segment 

 bifid at the extremity ; all above, with the exception 

 of the tentacula and rostrum glabrous, reddish- brown, 

 beneath paler. 



Inhabits East Florida. 



Cabinet of the Academy and Philadelphia Mu- 

 seum. 



Var. a. With three or four fuscous revolving 

 lines 5 base of the aperture narrower than in the spe- 

 cies. 



Length seven-twentieths of an inch. 



Inhabits the coast of Maryland and New Jersey. 



These shells inhabit the salt marshes, and have 

 the habit of crawling up the culms of grasses, and 

 other plants. I observed them to be very numerous 

 near the mouth of St. John's river. It is sufficiently 

 distinct from the M. coniformis by the paucity of 

 striae on the labrum. 



The variety is a very common inhabitant of our 

 coast, and is very possibly a distinct species, as it is 

 lineated and is narrower at base ; if so, it may be 

 called lineatus. 



