318 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Buccinum Sanderson! VciTill. 



Trans. Conn. Acad., v. n. 400, pi. V8, fig. D (uucleus), Jnue, 18S2. 

 Shell elongated, browuisb, trausluceut, rather thiu aud delicate, with 

 a high spire: well impressed suture ; strongly convex, obliquely ribbed 

 and strongly, spirally sculptured whorls ; a large, smooth, mammillary 

 nucleus; a small aperture: aud a short, nearly straight columella. 



Whorls, in our largest example, seven, a little flattened below the 

 suture, strongly convex in the middle; the penultimate whorl with about 

 13 broadly convex, curved ribs or undulations, stronglj- excurved at the 

 middle of the whorl ; on the body-whorl the ribs are less prominent and 

 fade out below the middle : on the three upper whorls they are absent. 

 The spiral sculpture, on the lower whorls, consists of prominent, narrow, 

 rounded cinguli, unecpial in size and separated by narrow grooves; 

 usnally there are three or four smaller and lower cinguli between two 

 of the larger ones, and sometimes a narrow groove appears on the larger 

 ridges, dividing them into two ; on the anterior part of the body-whorl 

 the cinguli become more uniform in size and more numerous. The whole 

 surface is covered with fine distinct lines of growth, which decussate the 

 cinguli and mostly cross the ribs somewhat obliquely. 



The nucleus is rounded and remarkably large for the genus (2'"'" in 

 diameter), translucent glossy brown, nearly smooth for about one turn 

 and a half; the apex is regular aud not obliquely raised. 



The aperture is unusually small and short, elliptical, a little contracted 

 posteriorly; outer lip thiu, well rounded, the edge receding in a broad 

 curve below the suture; canal short and narrow; columella rather 

 straight, thiu, with the folds slightly developed, the anterior end thiu, 

 rounded, and projecting quite as far as the lip; the upper part of the 

 columella-lip is not excavated, nor distinctly excurved. The operculum 

 il5 small, pale yellow, rounded-elliptical, with the nucleus at about the 

 middle of the length, aud a little to one side of the center. Epidermis 

 thin aud smooth. Color of the shell, with epidermis, yellowish brown to 

 dark reddish brown, sometimes with small whitish spots on the larger 

 spiral ridges; columella whitish, inside of aperture pale orange-brown 

 or light amber. 



Our largest example (female) is 40™'" long; breadth, 21"'"'; length of 

 "body whorl, 29.5"^'"; length of aperture, 21.5""" ; its breadth (lip broken), 

 12™'"; length of operculum, 11.5™"'; its breadth, 9™™. A male has very 

 nearly the same propc»rtions. 



Off Martha's Vineyard, station 939, in 25S fathoms; station 1032, in 

 208 fathoms, 1881, two living examples, male and female. 



This species resembles some of the varieties of B. nndatiim, but besides 

 its more slender and elongated form and more delicate texture, it difl'ers 

 decidedly in the character of the spiral sculi)ture, the shortness and 

 small size of the aperture, and in the operculum ; but the most striking 

 difl'erences are in the nucleus aud upper whorls, for the nucleus is more 



