44 



BULLETIN ()S, UNMTEI) STATES NATIONAL MX^SEl'M. 



TURBONILLA (STRIOTURBONILLA) VANCOUVERENSIS Baird. 



Plate 4, fi.sr. 9. 

 Chemnitzia vaacouverens is Baird, Proc. Zool. Soc, 1863, p. 67. Turbonilla {Strio- 

 turbonilla) vancouverensis (Baird), Dall, and Bartsch, Proc. U. S.Nat. Mus., 

 vol. 30, 1907, pp. 495-496, pi. 44, %. 1. 



Shell solid, rather broad and stout, siibdiaphanous, bluish to milk- 

 white. Nuclear whorls two, lar^je, heUcoid, partly obliquely im- 

 mersed in the first of the later turns. Post-nuclear whorls well 

 rounded, with the o;reatest convexity on the lower half of the exposed 

 portion; ornamented by about 10 very broad, strong, slightly pro- 

 tractive axial ribs on the second, 14 on the fifth, 16 on the eighth, and 

 18 on the penultimate whorl. These ribs terminate before they reach 

 the periphery of the whorl, leaving a plain band above the suture, as 

 in T. torquata Gould, but not as broad as in that species. Intercostal 

 spaces deep, narrower than the ribs. Sutures well marked by the 

 shouldering at the summit and the sudden sloping of the ribs just 

 above the periphery of the whorls. Aperture subovate; lip thin, 

 joining the short, somewhat re volute columella in an even curve. 

 Entire surface marked by faint, wavy, spiral striations. The speci- 

 men figured has 10 post-nuclear whorls, and measures : Length, 6 mm. ; 

 diameter, 1.8 mm. 



Another specimen from the same locality, which has 12 post- 

 nuclear whorls but is minus the nucleus and probably the first of the 

 succeeding turns, measures: Length, 9.2 mm.; diameter, 2.5 mm. 



This species resembles T. torquata Gould, but can easily be dis- 

 tinguished from it by its broader base, its large, partly immersed, 

 slanting nucleus, and the robust character of its whorls and ribs, the 

 latter being fewer and much broader; the intercostal spaces being 

 comparatively narrower. Baird's cotypes, three specimens, were 

 taken from the crop of a pintail duck shot in Esquimalt Harbor, Van- 

 couver Island, British Columbia; they are in the British Museum. 



The following sjiecimens have been exaniined : 



U.S.N.M. 

 cat. no. 



169489. 

 1G0490, 

 160993 

 126670 



44938. 

 196184 



196183 



No. of 

 speci- 



Localitr. 



Depth, 

 fath- 

 oms. 



Collector. 



Disposition of 

 material. 



W. H. Dall U. S. Nat. Mus. 



Do. 



Do. 



Kadiak Island, Alaska [ 13 



Lituya Bay, Alaska j 8 do 



I'ort'Etches, Alaska i do 



Victoria, Vancouver Is- j C.F. Newcombe. 



land, British Colombia. i 



Puget Sound, Washmgton C. B. Kennerley . 



Carter Bay, British Colum- | G. W. Taylor. 



bia. 



do do Taylor coll. 



i'ort Smipson, British Co- do U.S. Nat. Mus. 



lumbia. i „ , 



.do do Taylor coll. 



Do. 



Do. 

 Do. 



West of Rose Spit, Queen do. 



Charlotte Island, British 



Columbia. 

 Alert Bay, British Colum- , do. 



bia. 

 Departure Bay, British do. 



Columbia. 

 .. do do. 



Do. 



Do. 

 Do. 



U. S. Xat. Mus. 



