230 



*TURBINELLA. 

 voluta pyrum. — Linn, 

 Sowerhys Genera, No. 2, pi. 2. 



The greater number of these shells were classed by 

 Linnaeus with the G. Voluta, and others with the G. Mu- 

 rex, but although the columella is singularly plaited, 

 they have a much greater affinity to the G. Murex than 

 to the G. Voluta; the canal at the base of these shells 

 is however a sufficient distinction to separate them from 

 the latter, and the want of varices clearly distinguishes 

 them from the former. It does not at first appear easy to 

 draw a line between this genus and that of Fasciolaria, 

 nevertheless the position of the plaits on the columella 

 is so peculiarly different, that a separation is fully war- 

 ranted. Shell turbinated or fusiform, canaliculated 

 at the base; spire more or less produced; columella 

 with from three to five projecting plaits, compressed 

 and transversely placed; exterior coated with an epi- 

 dermis, aperture closed by a pear-shaped horny oper- 

 culum; columella lip frequently sharp, thin, and re- 

 flected. In the Tankerville collection is an hetero- 

 strophe or reversed example of this genus, specimens of 

 which air extremely* rare and valuable. 



