96 TRACHELIPODA. 



Genus 51— STOMATIA.— Zawiarc/t. 



Generic Character. — Shell ear-shaped, imperforate ; spire 

 prominent ; aperture entire, oblong, and large ; outer lip 

 elevated as much as the pillar ; back with a transverse sub- 

 carinated tuberculated rib. 



Stomatia phymotis. — The Tumoured Stomatia, Plate 

 XIL fig. 29. Ovate oblong; back convex, striated, nodu- 

 lous, and white ; spire small, contorted ; lip thin and acute. 

 Three and a fourth inches long. Inhabits the Indian ocean. 



Genus52.—8TO'MkTELLX.— Lamarck. 



Generic Character. — Shell orbicular or oblong, ear-shaped, 



imperforate ; aperture entire, large, elongated ; outer lip 



effuse, dilated, and open. 



This shell is distinguished from Stomatia, by its never having the 

 transverse rib of the species of that genus. 



Stomatella imhricata The Imbricated Stomatella. 



Plate XII. fig. 30. Suborbicular, convex, somewhat de- 

 pressed, rough, having thick-set transverse ribs, covered 

 %vith imbricated scales ; grayish-brown. More than an inch 

 and a half long. Inhabits the Indian ocean. 



Genus 53— SIGARETUS.—Zamarc^. 



Generic Character. — Shell subauriform, suborbicular ; 

 outer lip short and spirally intorted ; aperture entire, very 

 expanded, ovate oblong ; the margins disunited. 



Sigaretus somewhat approximates the genus Natica, and much re- 

 sembles a depressed shell of that genus, from vihich, however, the 

 extraordinary width of the ajjerture, and its spiral short columeUa 

 render it quite distinct. 



Sigaretus concavi/s The Concave Sigaretus. Plate 



XII. fig. 25. Ovate, back convex, covered with transverse 

 undulated striae ; reddish-yellow, spire white, somewhat 

 prominent; aperture expanded, concave; umbilicus deepish. 

 Inhabits the Indian ocean. 



