TO GEOLOGY. 129 



Observations. This species is very closely allied to the 

 above, but may at once be distinguished by the transverse 

 striae which alternate in this. The longitudinal stria3 are 

 not so close, nor are they imbricate. 



T.sukata. Plate 4. Fig. 119. 



Description. Shell elevated above, rounded below, 

 with numerous transverse furrows, the two superior ones 

 being indistinct ; substance of the shell rather thin ; apex 



not acute ; suture impressed ; umbilicus ; whorls 



inflated; mouth . 



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



Observations. This fragment resembles so closely the 

 two species above described, that I have with but lit- 

 tle hesitation placed it in the same genus. It has 

 apparently lost only one whorl seven remain. It is 

 rather more alternate than the preceding, and differs 

 entirely in being furrowed, and having no longitudinal 

 striee. Some of the parts being absent, I am neces- 

 sarily compelled to make an unfinished description and 

 figure. 



GENUS TURRITELLA. Lamarck. 



T. carinata. Plate 4. Fig. 120. 



Description. Shell turrited, transversely striate and ca- 

 rinate ; apex acute ; substance of the shell thick ; suture 



