356 DESCRIPTIONS OF NEW SPECIES OF FOSSILS 



STROMBINA, Morch. 

 S. LiMONENSis, Gabb, ii. s., PL 46, fig. 40. ' 



Shell minute, robust, spire elevated, as long as the mouth ; whorls eight, sides 

 nearly flat, very gently convex and sloping regularly outvv'ards ; suture incised ; 

 surface perfectly plain, except on the canal and extreme anterior part of the body 

 volution where there are half a dozen impressed obliquely revolving lines. Aper- 

 ture not very broad; outer lip deeply notched, below which it is very thick; 

 ridged internally ; inner lip not heavily encrusted. 



Length 3 mm. 



The figure is inaccurate in the columellar region. The anterior part is drawn 

 straight and narrow, whereas it should encroach much more on the mouth in its 

 anterior third, below which the columellar margin should slope bacjcwards to the 

 end of the canal. For the anterior two-thirds of the mouth the columella should 

 be nearly a third wider, encroaching that much more on the aperture. 



S. EXiLis, Gabb, ii. s., PL 46, fig. 41. 



Shell small, narrow fusiform ; spire high ; whorls eight and a half, including 

 the nucleus, smooth, convex ; suture well marked ; body whorl marked by a few 

 revolving lines on the anterior half; aperture one-half the length of the shell ; 

 narrow, produced in front into a broad, slightly recurved canal; inner lip lightly 

 encrusted ; outer lip thickened and internally toothed. 



Somewhat smaller than S. bicanaJiculata, this plain little shell can be at once 

 distinguished by the absence of the great posterior canal. The outer lip is the 

 least thickened of any species of the genus known to me, and in this character, as 

 well as in the absence of all tuberculation, the shell shows an approach to the 



genus Amycla. 



CASSIS, Lam. 



C. JLAMMEA, Lam., A. S. V. (Desh. Ed.), v. 10, p. 22. 



The common large West Indian shell is represented by one large characteristic 



» 



specimen, 



CASSIDEA, Brug. 



C. GRANULOSA, Brug., Enc. Meth., v. 1, p. 421. 



Common in the West Indies, both recent and fossil. 



CASSIDARIA, Lam. 



C. L^viGATA, Sby., Q. J. G. S., v. 6, p. 47, PL 10, fig. 2. 

 C. SUBL^EVIGATA, Guppy, loc. Git., V. 22,. p. 28t, PL 17, f. 10. 



The Costa Rican specimens, in their greater amount of striation, are nearer to 



