164: PROCEEDINGS OF THE ACADEMY OF [April, 



1| smooth, strongly convex embryonic whorls, 4| subsequent 

 whorls, which are separated by a very deep y channelled suture ; 

 the last whorl therefore being bluntly carinate abov and at the base. 

 Sculpture of strong, narrow, retractive axial ribs, 14 on the last 

 whorl, passing over the carinse at summit and base; crossed by numer- 

 ous, unequal, low spiral cords. The aperture has two strong lirae 

 within the straight upper margin, eleven within the outer. The 

 inner lip has many entering wrinkles, and three columellar plaits, 

 the anterior one low and obtuse. 



Length 24.5, diam. 21 mm. 



Type is No. 2989, A. N. S. P. 



This species is not at all like the recent C. hrevis Sowb. It closely 

 resembles C. perspediva Conr., of the Chesapeake Miocene, but 

 differs in its more rugose aperture and narrow, irregular ribs, which 

 in C. perspectiva are wide and regularly alternating. The aperture 

 and umbilicus are larger than in C. depressa Dall, of the Tampa 

 silex beds. It differs conspicuously from C. moorei Guppy in the 

 basal region. 



A Trigonostorna figured by Toula, referred to above, appears to be 

 close to C. insularis, perhaps specifically identical. 



Oliva proavia n. sp. 



Oliva cylindrica Sby., Gabb. Tr. Amer. Philos. Soc, XV, 1873, p. 215 (pars 



secunda). 



The shell is somewhat fusiform, the upper fourth of the last whorl 

 and the spire tapering, forming a straightly conic spire. In its even 

 surface the suture appears as an engraved groove, the individual 

 whorls being flat. The first two whorls form a minute, mammillate 

 apex. Whorls 9. The aperture occupies almost exactly f of the 

 total length. Columella is rather heavily calloused, and bears about 

 21 very oblique plaits, of which all but about 10 in the median part 

 are quite small. There are faint traces of a color pattern resembling 

 that of 0. sayana Rav. 



Length 81.5, diam, 27, aperture 62 mm. (type). 

 " 101, " 37, " 86.5 " 



The type and a larger specimen are No. 2992, A. N. S. P. 



Comparing the two large . specimens with 0. sayana Rav. (0. 

 litterata Lam., 0. carolimensis Conr.) we note the more slender con- 

 tour and much more oblique columellar folds of 0. proavia. A further 

 important distinction is that the lateral contours of the spire are 

 continuous across the suture in proavia, while in the other species 

 the posterior edge of each whorl projects beyond the preceding. 



