84 POST-PLEIOCENE FOSSILS. 



Chemnitzia interrupta, Gould, Invert, of Mass., p. 268, fig. 173. 



Chemnitzia interrupta, Stimpson, Boston So. Nat. Hist., Proceed., Vol. 4, p. 16. 



Chemnitzia interrupta, Stimpson, Shells of New-England, p. 41. 



Turbonilla interrupta, H. $ A Adams, Gen. Mollusca, Vol. i, p. 231. 



Description. There is only a slight difference in this shell from the two first named 

 species, T. exarata, and T. nivea, (page 83.) Like the last named, the ribs are straight 

 but more numerous, and the grooves are crossed by about fourteen fine revolving lines, 

 which are interrupted by the ribs ; in some specimens the lines appear to be in pairs when 

 seen through a lens. 



Plate XIII. Fig. 4, Natural size. 

 " 4a, Magnified. 

 " 4b, Magnified rib and groove. 



Locality. Simmons'. Museum, College of Charleston; Cabinet F. S. H. 



TURBONILLA. C A N C E L L A T A. — {New Species.) 



Plate XIII. Figs. 6, 6a, &>. 



Description. The whorls of this species are more inflated than any of the foregoing; 

 the sutures are deeper and angular, and the grooves are crossed by four lines, one 

 equidistant from the sutures, and a pair in the middle. To the unassisted eye the shell 

 appears beautifully cancellated. 



Plate XIII. Fig. 6, Natural size. 

 " 6a, Magnified. 

 " 6b, Magnified ribs, grooves, and revolving lines. 



Locality. 'Simmons'. Museum, College of Charleston; Cabinet F. S. H. 



