MOLLUSCA. 671 



Order CTENOBRANCHIATA. 



Sub-order PLATYPODA. 

 Super-family GYMNOGLOSSA. 



Family BULIMIDAB. 

 Genus LEIOSTRACA H. and A. Adams. 



Leiostraca cretacea (Conrad). 



Plate LXXV., Figs. 15-17. 

 1869. Eulima cretacea Con., Am. Jour. Conch., vol. 5, p. 100, 



pi. 9, fig. 15. 

 1892. Leiostreca cretacea Whitf., Pal. N. ]., vol. 2 (Monog. 



U. S. G. S., vol. 18), p. 150, pi. 19, figs. 2-5. 

 1905. Hulima cretacea Johns., Proc. Acad. Nat. Sci. Phil. 



(1905), p. 20. 



Description. "Shell small, slender, subulate, spire very much 

 elevated, smooth and polished; volutions nine or more (eleven, 

 Conrad), flattened between the sutures, the upper edge of any 

 volution slightly smaller than the lower edge of the one imme- 

 diately above it, making the sutures remarkably distinct for a 

 shell of this group; body volution rounded subangular in the 

 lower part and rather rapidly contracted below to the short 

 columella; aperture ovate-elliptical, acute above and rounded 

 below ; outer lip thin and sharp, inner lip smooth, without callus 

 or ridges; surface polished, entirely destitute of lines or other 

 markings. On one individual, on which the lip is broken away 

 for one-third of the volution, there occurs a distinct spiral ridge 

 above the columella proper and just below the junction of the 

 outer lip with the body of the volution, within the aperture." 

 (Whitfield.) 



The dimensions of one of the type specimens are: height, 5.6 

 mm.; greatest diameter, 1.6 mm. ; apical angle, 16. 



Remarks. This species is known only from the specimens col- 

 lected near Haddonfield many years ago. 



Formation and locality. Woodbury clay, near Haddonfield 



(183). 



Geographic distribution. New Jersey. 



