142 CONTRIBUTIONS 



one third the length of the shell; columella with two 

 folds. 



Length 5-20ths, Breadth .1 , of an inch. 



Observations. The strongly characterised longitudinal 

 ribs of this species eminently distinguish it. At the base 

 there are a few indistinct transverse striae, but the larger 

 part of the whorl is entirely free from them. Among those 

 here described, this is the only one with this character. 



C. parva. Plate 5. Fig. 141. 



Description. Shell somewhat elevated, turrited, with 

 large longitudinal folds cut by large elevated transverse 

 striae, spire elevated, obtuse at the apex; suture deeply 

 impressed ; whorls five, convex ; umbilicus very small ; 

 mouth semilunate ; columella furnished with two large 

 folds ; outer lip sharp, within crenulate. 

 Length .2, Breadth .1, of an inch. 



Observations. This truly beautiful little species is very 

 distinct from either of the others here described. It may 

 be at once known by its strong folds on the columella, 

 and its large longitudinal folds and strong transverse striae. 



The genus Cancellaria has been observed in England 

 only in the London Clay, from whence three species have 

 been described.* M. Deshayes's Tables give forty-two 



* Min. Conch, pi. 360 and 361. 



