172 CONTRIBUTIONS 



nate ; substance of the shell rather thin ; spire somewhat 

 produced, acute at the apex ; suture small and irregular ; 

 whorls seven, subangular above ; mouth rather narrow ; 

 columella with two folds ; outer lip sharp. 



Length .9, Breadth .5, of an inch. 



Observations. This is the largest species I have noticed 

 from this deposit. It occurs one half longer than the in 

 dividual figured. It more strongly resembles the V. spinosa 

 (Lamarck) than any species I know, but differs somewhat 

 in the form, and in not having such strong spines on the 

 superior part of the whorl, these in our species being re 

 placed by very short spines or compressed tubercles. In 

 some specimens these are disposed to be double, and in 

 others the spines lengthen down the sides and form a kind 

 of rib. A third, very small fold, may sometimes be ob 

 served in this species above the two large ones. 



V. gradlis. Plate 6. Fig. 180. 



Description. Shell ovately turbinate, transversely striate 

 below, longitudinally and closely ribbed above, coronate ; 

 substance of the shell thin ; spire turrited ; suture linear ; 

 whorls six, angular and canaliculate above ; mouth nar 

 row, straight ; columella with two folds ; outer lip sharp. 



Length .6, Breadth .3, of an inch. 



Observations. This differs from the Defrancii, in being 

 striate only on the inferior part, and in having close longi 

 tudinal ribs. The end of the ribs are disposed to be granu 

 late at the angle. 



