368 PROCEEDINGS OP THE ACADEMY OP 



name it. The fragment consists of the principal part of the body whorl, inclu- 

 ding the anterior two-thirds of the mouth and, on the opposite side, the sur- 

 face, almost to the suture. It resembles somewhat V. mutabilis Con., but the 

 body whorl is more convex in the middle, although the shell was more 

 slender in its outline. Shell thick, mouth narrow, curved and more regular in 

 its width than V. mutabilis. Columellar lip with three very prominent rounded 

 folds, the anterior one most oblique and ending gradually at its outer extremity. 

 The upper two end abruptly, the upper one most decidedly so. These folds are 

 as high as the thickaess of the shell, while in mutabilis they are always faint, 

 sometimes almost obsolete. Columella very tortuous, reflected somewhat up- 

 wards at its extremity, when the shell is in its natural position. Surface 

 smooth. 



Length of body whorl about 2-5 inches ; width about 1*25 inches. 



TCBBONILLA. 



T. a s p e r a. Shell elongated, acute ; spire very high, whorls ten or eleven : 

 suture distinct. Mouth ovoid, slightly expanded at the inner anterior margin, 

 angulated behind ; columella nearly straight. Surface of the whorls most pro- 

 minent a little below the middle, and marked by about ten very prominent lon- 

 gitudinal ribs not continuous from one whorl to another. These ribs are 

 crossed by three revolving lines, which take the form of acute ribs between the 

 longitudinal ones, but develope into large nodes on their crest ; under surface 

 of the body whorl marked by fjur additional plain revolving ribs, becoming 

 smaller in advance. 



Length -28 in.; width of body whorl -08 in.; length of mouth '06 in. 



From the Miocene of Santa Barbara, Cal. 



Modelia Gray. 



M. striata. Shell turbinate; whorls five, rounded above. Suture simple, 

 well marked. Mouth about half the length of the shell, angulated above, 

 broadly rounded below, and somewhat expanded anteriorly. Outer lip simple ; 

 inner lip simple above, marked by a thickened line inside the margin, in ad- 

 vance of the umbilicus and extending to the middle of the anterior margin. 

 Umbilicus small, deeply perforated and bordered by a sharp line. Surface 

 marked by minute revolving strke, very numerous, most distinct on the under 

 surface of the body whorl ; and a few larger lines of growth. Outline of the 

 whorls regularly but slightly convex above, concavely truncated below, and 

 with the lower angle marked by a sharp angular revolving ridge immediately 

 below the line where the succeeding whorl conies in contact with the surface, 

 so that it is only visible on the body whorl. 



Length -2 in.; width of body whorl -14 in. ; length of mouth -1 in. 



From Santa Barbara, Cal. Miocene ? 



The carina on the lower angle of the whorl appears, on a cursory examina- 

 tion, to be the broken remains of the mouth, on account of its proximity to the 

 posterior end of the outer lip ; but is, in reality, a normal character, is a very 

 little below the edge of the lip, and is found at all ages of the shell, becoming 

 in adult shells somewhat less marked as it approaches the extremity, on the 

 body whorl. In advance of it, the lip is very faintly emarginate. 



Rocellaria Fleuriau de Bellevue. 



R. antiqua. Shell cuneiform, very widely gaping in front. Beaks small 

 involuted ; anterior but not terminal. Cardinal margin straight for about half 

 the width of the shell, joining the posterior margin, which continues a short 

 distance, nearly parallel with the basal edge. The posterior extremity is 

 broadly and regularly rounded. Basal margin nearly straight, the hiatus be- 

 tween the valves continuing from the extreme anterior end almost to the pos- 



[Nov. 





