﻿DALL] SHELLS* COLLECTED IN Mil'- BAHAMAS 443 



Cerion oweni new species. PI. lviii, figs. 3, 8, 10, 12. 



Typical form south side of Little Abaco, opposite Marsh Harbor, 

 and on the opposite shore of Grand Bahama at Riding Point ; variety 

 reticulatum at the Sugar Loaves, reeks northwest of Elbow Cay, off 

 Great Abaco; variety incisum (nearly all dead or subfossil). 

 Stranger ( ay, northwest of Little Abaco, and one specimen, appar- 

 ently the same, at Sweeting's village, Little Harbor, Great Abaco; 

 var. vermiculum at Mathews Point, south side of Great Abaco. This 

 member of one of the most difficult groups of Cerion has been sub- 

 mitted to Dr. Pilsbry, who regards it as new and forming a parallel 

 series to C. agrestinum Maynard, from New Providence. As he has 

 recentlv monographed the group I have adopted his opinion. The 

 species is named in honor of Mr. Owen Bryant, the collector. 



Typical form. PI. lviii. fig. 12.— Shell large, slender, ashy white, 

 or white marbled and longitudinally streaked and clouded with nut 

 brown of varied intensity ; the apical 2)A whorls subtranslucent, the 

 remaining ten opaque, smooth and somewhat polished, or more or 

 less sculptured by fine oblique wrinkles with subequal interspaces 

 about three to one millimeter on the line of the suture ; apex beehive- 

 shaped ; remainder of the shell subcylindric, the last whorl rising 

 a little near the aperture, the peristome thickened, somewhat re- 

 flected, rounded, simple, waxen white ; throat brownish, with a short 

 low parietal and feeble axial lamina or ridge of callus ; umbilicus 

 with a deep narrow chink ; the sutures are not impressed ; the imma- 

 ture shells are trochiform, with a narrow axial perforation, a small 

 sharp lamina on the pillar, usually a short feeble tooth on the roof 

 of the aperture and very rarely a faint trace of a callosity on the basal 

 wall also, but I have noticed this only once or twice ; measurements 

 of the mutations of this species show the following as divergencies 

 (U. S. Nat. Mus., No. 179,44^) : 



Surface. Whorls. 



Smooth 12.5 



Smooth 10.5 



Feebly striate 12.5 



Sharply striate 12.0 



Sharply striate 12.0 



Feebly striate 9-5 



Subreticulate 11.0 



Subreticulate 9-5 



Very sharply striate.. 12.0 



Very sharply striate.. 10.0 



Very sharply striate.. 11.0 



Very feebly striate.... 10. o 



Feeblv striate 10.0 



