148 



p. 185. It has a small oblong aperture, no umbilicus, and the columella 

 is furnished at the upper part with a small winding plait, more or less 

 obscurely developed. 



Although Mr. Lea notices a recent species, which he proposes to call 

 Monoptygma Melanoides, he does not accompany the name with any de- 

 scription. The species here figured, is a sharp subulate shell, rounded at 

 the base, composed of about ten whorls of a convexly flattened growth, each 

 encircled by six fine equidistant linear grooves. The sutures are somewhat 

 deeply impressed, and there is no indication of any umbilicus. It is of 

 rather solid structure and evidently of marine habits. 



Figure. 



Monoptygma cinerea. PI. 15. Sp. 76. Shell, showing its small entire 

 aperture. — From Mr. Cuming's collection. 



Genus 18. EULIMA, Risso. 



Animal ; unknoion. 



Shell ; subulate, frequently very peculiarly obliquely distorted, 

 not umbilicated, polished ivory white, shining, whorls gene- 

 rally distinguished by a flattened or channelled varix ; colu- 

 mella arched, aperture small, entire, lip) simple, obtuse. 



The genus Eidima, established by Bisso, includes a limited, but extremely 

 natural group of small subulate shells, distinguished by their solid structure 

 and white enamelled surface, shining like porcelain. Many of the species 

 have likewise a curious distorted obliquity of growth, occasioned in some 

 measure by the formation of a row of channelled varices, consisting of one 

 in each whorl deposited a little in advance of that which precedes it. 



The typical species of this genus is the Turbo politus of Linnaeus, 

 Dillwyn, and Montagu; Turho suhdatus of Donovan and Dillwyn is also one 

 of the group, and M. Deshayes refers Melania nitida of Lamarck to Euli- 

 ma. Of the species figured under this head in Sowerby's ( Conchological 

 Illustrations/ a portion of them have been separated by M. Deshayes for 

 ample reasons under the title of Boncllia, properly Niso. 



The Eulimee are very distinct in their generic character, having little 

 affinity with Scalaria and less with Melania ; there are one or two species 

 on the southern shores of Europe, one from New Holland, and two or 

 three species inhabit the Pacific Islands. 



