192 Mr. Cosmo Melvill on the 



in the Tropics to one in Lieut. Hankey's day, now nearly 

 fifty years ago. This NaturaHst adds that when the 

 Cowry had virtually become naked and defenceless, in a 

 short time a thin layer, of the frail consistency of shell-lac, 

 began to cover it, and it assumed the form of a Cymba, of 

 the family Volutidse, but owing to the extreme delicacy of 

 the organization, he could not preserve any specimens. 



(VII.) Generic and siibgeneric divisions, hitherto adopted. — 

 Dr. Gray's subdivision of the genus, adopted with some 

 modifications by Messrs. Adams, 1858, in their "Genus of 

 Recent Mollusca," Vol I., p. 263, is as follows : — • 



CypR/EA (L.). 



Shell ovately cylindrical, polished ; spire obsolete, or 

 concealed by enamel ; aperture narrow, linear, inner lip 

 denticulated ; outer lip greatly inflected, denticulate or 

 crenate. 



Type C. talpa (L.). 32 sp. 



Aricia (Gray). 



Shell ovate, dorsally gibbous, flattened at the base, the 

 sides thickened and dilated, polished ; spire concealed ; 

 aperture narrow, linear ; inner lip gently expanded and 

 callous, dentato-lirate ; outer lip dilated, flattened and 

 callous, dentato-lirate. 



Type A. annulus (L.). 21 sp. 



LUPONIA (Gray).-'^ 



Shell ovately pyriform, ventricose, smooth, polished ;, 

 spire concealed, often depressed ; aperture narrow, linear, 

 inner lip plicato-dentate, the plaits often obsolete pos- 

 teriorly ; outer lip inflexed and crenate. 



Types L. tigris (L.), L. Algoensis (Gray). 59 sp. 



*Of L. Edentula (Sowb.) Mr. Roberts has made a genus Gaskoinia, 

 the only characteristic of which is that the teeth are obsolete. As, however, 

 .some specimens are slightly toothed, I see no necessity for maintaining this, 

 name even as a subdivision. 



