TURBINACEA. MOLLUSCA. MARGARITA. 255 



This beautiful shell cannot be mistaken for any other species on the 

 American Atlantic coast. Its color, its regular spiral lines, undulated 

 sutural region, and pearly aperture, render it a very beautiful shell, 

 having more of the aspect of a tropical, than of a northern shell. Mr. 

 Sowerby's description and figure were published in the same month 

 in which Mr. Couthouy read his description to the Boston Society of 

 Natural History ; and we must, therefore, allow his name the right of 

 priority. 



There is considerable variety in the coloring ; the freshest young 

 shells are of a rose-red, and of a more depressed form ; the majority 

 are of a brownish red ; the undulations are seldom, but sometimes, 

 wanting. 



MARGARITA A'RCTICA. 



Shell orbicular, depressed, smooth and shining, translucent, of 

 a light horn-color, with veryjine revoking lines on the base ; aper- 

 ture circular. 



FIGURE 163. 



State Coll., No. 36. Soc. Cab., No. 895. 



Margarita arctica, LEACH ; in Ross's Voyage of Discovery, 8vo. 1819. Appendix. 

 SOWERBY; Malacol. and Conchol. Mag., part i. 25. Conchol. Must., (Marga- 

 rita), f. C. 



Margarita helicoides, BECK ; MS. 



Turbo inflatus, TOTTEN ; Silliman's Journ., xxvi. 368, f. 5, a, b, c. 



Paludina inflata, MENKE ; 



Shell small, orbicular, depressed, thin and translucent, smooth 

 and shining, of a light yellowish horn-color or light olive ; whorls 

 four or five, very convex, the last very large and tumid, a little 

 flattened above ; minutely wrinkled by the lines of growth, and at 

 its base marked with very fine spiral lines ; suture well impressed ; 

 aperture large, circular, somewhat expanded ; edge sharp and 

 simple, a little reflected at the umbilicus, which is large and pro- 

 found, not bounded by an angular ridge ; operculum horny, multi- 

 spiral. Length ^ inch, breadth nearly -^ inch. 



Found abundantly on all our sandy beaches. In some seasons, 

 however, I have looked for them almost in vain. Their proper 

 habitat is the deep sea, as they are thrown up alive, on the large 



