A NEW WEST INDIAN FOSSIL LAND SHELL. 



By Paul Bartsch, 



Curator of Marine Invertebrates, United States National Museum. 



Among a lot of kitchen midden marine shells collected by Theodoor 

 de Booy on Salt Kiver, North Coast of St. Groix, and submitted to 

 the United States National Museum for determination, is the shell 

 of a Pleurodonte belonging to the Section Caracollus. A critical 

 comparison shows it to be quite distinct from all the other known 

 members of the group. I therefore name it : 



PLEURODONTE DEBOOYI, new species. 



Plate 93. 



Shell large, very broadly conic, depressed above and well rounded 

 below. Upper surface grayish-white excepting the nuclear turns, 

 which are rusty brown ; and a band of the same color about one-fifth 

 as wide as the whorl situated about half the width of the dark band 

 posterior to the periphery. The basal side is of the same general 

 color as the upper and bears a rusty spiral band a little distance 

 anterior to the periphery. All the whorls are flattened. Suture 

 scarcely indicated, not at all impressed. Periphery strongly cari- 

 nated. Base slightly inflated, strongly rounded, with a narrow, 

 shallow, impressed umbilical pit. Aperture subtriangular, oblique; 

 outer lip thickened at the edge, the upper less so than the basal, 

 the latter as well . as the columellar portion much thickened and 

 reflected; parietal wall covered with a thin callus. Entire surface 

 both above and below^ marked by moderately strong, decidedly re- 

 tractively curved incremental lines and the exceedingly fine, crinkly, 

 crisscross markings characteristic of all the members of the section. 



The type (Cat. No. 218039, U.S.N.M.), was collected by Mr. Theo- 

 door de Booy in kitchen midden deposits on Salt River in northern 

 St. Croix, West Indies. It has six whorls and measures — altitude, 

 26 mm. ; greater diameter, 58 mm. ; lesser diameter, 49 mm. 



Proceedings U. S. National Museum, Vol. 54— No. 2254. 



605 



