PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 319 



than twice as large as that of B. midatum, and different in cliaracter; 

 wLile on the second and third whorls the spiral ciuguli are fewer and 

 very much more prominent and coarser. The character of the nucleus 

 and upper whorl will also distinguish it from all the other species of 

 our coast. 



I have named this interesting shell in honor of Mr. Sanderson Smith, 

 of the U. S. Fish Commission parties during these explorations. 



Sijilio pubescens Verrill. 



Xe2)tiineai)ro2nnqitaYcvh\], Amer. Jouru. Sci., xvi, p. 210, 187S. 



Nej^tunea (Sipho) proplnqua Verrill, Amer. Jouru. Sci., xs, p. 391, Nov., 1880; 



Verrill, Proc. U. S. Nat. Mus., iii, p. 370, 1880 {nou Alder, Jeffrey.s, etc.). 

 Sipho puhescens Verrill, Tr. Couu. Acad., v, p. TjOl, pi. 43. fig. 6, pi. 57, fig. 25, 

 June, 1882. 

 Shell rather stout, fusiform, regularly tapered, obtuse at the tip of 

 the spire, with the suture deep and canaliculate. Whorls about seven, 

 broadly rounded and somewhat Hattened, narrowly but distinctly chan- 

 neled at the suture. 



Sculpture over the whole surface, regular and numerous shallow, 

 spiral grooves, or sulci, separated by slightly raised, flat, or somewhat 

 rounded cinguli, usually but not constantly wider than the sulci; on the 

 penultimate whorl there are about li to 1(3 of the sulci; slight but dis- 

 tinct curved lines of growth cover the surface. Aperture narrow ovate- 

 elliptical; outer lip broadly and regularly rounded, the edge receding 

 in the middle in a broad, concave curve; at the base of the canal the 

 lip is decidedly incurved. Canal moderately long, somewhat contracted, 

 spirally curved to the left and strongly bent backw^ard at the tip. Col- 

 umella very much bent, with a strong sigmoid curvature; portion o})- 

 posite the middle of the aperture greatly receding. Epidermis thin, but 

 firm, yellowish green to olive-green; when fresh and uninjured covered 

 with fine, short, capillary processes, forming spiral lines along the cin- 

 guli. 



Color of the shell white; inside of aperture translucent bluish white. 

 The nucleus is moderately large (diameter 2.15'"™), smooth, mammil- 

 lary; its first whorl is strongly turned up obliquely, and incurved. 



The median tooth of the radula is broad, with three denticles, the 

 middle one largest; the lateral teeth are large, with three sharp curved 

 denticles, the outer one much the largest, the middle one smallest; 

 occasionally the inner one bears a small secondary denticle on its outer 

 edge. 



Operculum long, ear-shaped, with the nucleus at the tip of the small 

 end, which is but little incurved; inner edge strongly convex beyond 

 the middle; outer edge broadly rounded. A female of the ordinary 

 adult size and form is G5'"'" long; breadth, 28"^™; length of canal and 

 body-whorl, 4G'"'"; breadth of body-whorl, 25'"'"; length of aperture, 

 SS"""^; its breadth, ll'""^; breadth of opening of canal at base, 5'"'". 



An average male is 50"'"' long; breadth, 26'""'; length of body-whorl, 

 40'"'"; its breath, 17'"'"; length of aperture, 31'"'" ; its breadth, 12'""'. 



