108 



American Se ash ells 



Margarites groenlandicus Gmelin 



Arctic Seas to Massachusetts Bay. 



Greenland Margarite 



Figure 3id 



H inch in length, % inch in width. Angle of spire 1 1 o degrees. Whorls 

 strongly rounded, aperture round, umbilicus wide and deep. Outer lip and 

 columella very thin. Base smooth; top of whorls with about a dozen smooth 

 spiral lirations or almost entirely smooth (form umbilicalis Broderip and 

 Sowerby). Nucleus glassy smooth. Suture finely impressed. Color glossy- 

 cream to tan. Aperture pearly. Commonly dredged from 5 to 150 fathoms. 



Figure 31. American A4argarites. 3l^ Margarites siiccinctiis 0^^:.,% inch (Vdici^c); 

 b, Solariella perainabUis Cpr., ^. inch (Pacific); c, Margarites piipilhis Gould, % 

 inch (Pacific); d, M. groenlandicus Gmelin, V^ inch (northern Atlantic); e, M. 

 liridatiis form parcipictiis Cpr., 14 ii^ch (Pacific); f and g, Solariella obsciira 

 Couthouy, 4 inch (Atlantic); h, Lischkeia cidaris Cpr., i inch (Pacific). 



Margarites lindatus Carpenter 



Santa Barbara, California, to the Coronado Islands. 



Lirulate Margarite 



Figure 3ie 



^ inch in length, 4 to 5 whorls, strong, semi-glossy. Very variable in 

 color (solid purple, whitish with dark-brown variegations and sometimes 

 with a spiral row of dark squares on the periphery), and variable in the num- 

 ber and strength of the small, smooth, spiral cords. Base rounded. Umbilicus 

 narrow but deep. Suture well-impressed. Interior iridescent. Common in 

 shallow water. M. parcipictus Cpr. and obsoletus Cpr. are forms of this 

 species. 



