Bartsch — New Marine Mollusks from America. 39 



Vitrinella (Docomphala) columbiana, new species. 



Shell moderately large, depressed helicoid, semitranslucent, bluish-white. 

 Nuclear whorls decollated. Postnuclear whorls gently rounded, almost ap- 

 pressed at the summit, marked by rather strong incremental lines which ex- 

 tend over both the upper and lower surface ; the lower surface is a little more 

 convex than the upper; the umbilical wall is marked by strong notches. 

 Aperture decidedly oblique, almost circular; parietal wall marked by a thin 

 callus, which renders the peristome almost complete. 



The type, Cat. No. 340,848, U. S. N. M., was collected by Mrs. Oldroyd 

 at Departure Bay. It has two and a half whorls remaining and measures: 

 altitude, 1.5 mm.; greater diameter, 3.1 mm. 



The present species is nearest related to Vitrinella {Docomphala) stearnsi 

 Bartsch, but differs from it in being a little more depressed, almost lacking 

 the sculpture of the upper surface of that species, and in having the umbili- 

 cus decidedly narrower and the notchings of the umbilical wall in the um- 

 bilicus much less pronounced. 



