T6 VOLUTID.E. 



numerons plaits of Lyria. Differs from Valuta in possessing an oper- 

 culum, and in dentition. I am unable to follow ]Mr. Crosse in this 

 separation from VoVutn, for several reasons: 



1st. The dentition of only a single species ( V. muncn) of the Volutes 

 with numerous columellar plaits has been exaniined, and there are 

 others, ]'. llebra'a, for instance, which cannot be separated conclio- 

 logically from V. musiea, but the dentition of which is unknown. 



2d. The assumed type of dentition of Valuta rests upon the examina- 

 tion of only three or four among the numerous species of the genus — it 

 may difter widely in some of the others 



;M. The presence of an operculum is proven in V. musica, but its 

 absence is not proven in most of the Volutes, although we know it to be 

 absent in several of them. The presence or absence of an operculum 

 has but little value in the classilication of some groups; indeed it is well 

 developed or absent in the, same species occasionally, as in Volutharpa, 

 etc. 



4th. If we assume V. Hehrcea and V. rirescens to be, with V. musica, 

 Volutolyriae, what shall we do with the groups Ilarpula and Fulgoraria, 

 which form the passage into the Volutes with few plaits ? 



.")th. If we adopt Volutu, Linn, or even the restricted Valuta of Gray, 

 in either case V. musica is the type, and if a new name is required it is 

 for those species the characters of which are difl'erent from V. musica.'} 



LYRIA, Gray. Shell ovately fusiform, solid; spire acuminate; whorls 

 longitudinally ribbed; aperture ovate, rather narrow; columella with 

 numerous transverse plaits; outer lij) simple, acute. Dentition, PI. 2, 

 fig. 7. 



The species are smaller than in Valuta, and Mitrteform, connecting 

 with the genus Mitra. 



MIC'ROVOLUTA, Angas. Shell small, ovately fusiform, solid, smooth, 

 shining; spire as long as the aperture, apex papillary; whorls simple; 

 aperture narrowly ovate; columella with four strong transverse plaits, 

 the anterior one the smallest; outer lip thin, simjjle, slightly contracted 

 at the base; base rounded, spout-shaped, with a tlexuous bend upwai'ds 

 towards the columella, which is a little thickened and reflected below 

 the plaits. 



The above description is drawn up from the only known species, and 

 probably many of its characters are of slight importance. The animal 

 is unfortunately unknown. 



Fossil Oenera. 



The following groups are enumerated by W. M. Gabb. They should 

 probably all be considered as subgeneric under Valuta rather than as 

 distinct genera. 



