414 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Genus NISO Risso, 1826. 
Shell deeply umbilicated, long-conical, polished, many-whorled, the apex very sharp; whorls 
nearly flat; aperture oval, pointed above, somewhat drawn out below; lip thin; operculum as in 
Eulima. 
Niso portoricensis, n. sp. Plate 57, fig. 4. 
Shell small, brilliantly polished, with about thirteen whorls; sides rectilinear, base rounded, apex 
acute; umbilicus deep, funicular, the umbilical side of the whorls convex, the umbilical carina distinct 
but not sulcating the aperture; apex and upper part of the whorls brown, intensified at the lines marking 
the periodical resting stages. At the periphery is a narrow pale zone, while the base is brown under a 
whitish superficies; peripheral angle not sharp, the whorls microscopically sharply axially striate 
with rather distinct fine grooves. 
Length, 9; diameter, 3.5 mm. 
Station 6062, Mayaguez Harbor, Porto Rico. 
This elegant shell is nearest to N. xglees Bush, but lias a different system of coloration. 
Family PYRAM1 DELUDE. 
Genus PYRAMIDELLA Lamarck, 1799. 
Shell with elevated, sharp- pointed spire, many-whorled, smooth; aperture suboval, entire, 
rounded in front; columella straight, with prominent spiral plications; operculum horny, semicir- 
cular, subspiral, the nucleus at the front end, its columellar edge notched to fit the folds of the 
columella. 
Pyramidella subdolabrata Morch. 
Obeliscus subdolabratus Morch, Mai. Blatt., xxn, p. 157; A. Adams, Thes. Conch., Pyramidella, p. 805, pi. clxxi, figs. 1-3, 1854. 
Shell of rather light structure, with about thirteen rounded whorls, which are narrowly shouldered 
below the suture; last whorl slightly ascending; surface apparently smooth, but seen to have fine, 
revolving sculpture under a lens, and this being crossed by the growth lines makes it faintly reticulate; 
aperture long-oval; outer lip slightly thickened, not toothed within; columella with a strong, sharp 
fold above, the two lower folds feebly developed; umbilicus narrow, deep. Color brownish white, with 
about three brown, revolving bands on the body whorl and two on the upper whorls; besides these 
there is a brown patch or band around the umbilicus. 
Length, 30; diameter, 13 mm. 
Fajardo, Porto Rico, one very fine shell. 
This species has been mistaken for the P. dolabrala of Linnaeus, but it has a duller color, lighter 
structure, and less strongly developed columella folds than that species. The bands of color are wider 
and less distinct than in dolabrata, and the reticulation of the surface is stronger. 
Genus TURBONILLA Risso, 1826. 
Shell slender, straight, many-whorled; whorls slightly convex, generally costulate; aperture 
simple, oval or subquadrangular; columella straight; lip thin; operculum having a spiral groove at its 
columellar border. 
1 Turbonilla reticulata C. B. Adams. 
? Chemnitzia reticulata C. B. Adams, Contr., 1850, p. 75. 
A fragment of a badly worn shell was obtained from dredgings taken at Mayaguez, which is 
probably this species. 
Section PYRGISCTJS Philippi, 1841. 
Turbonilla portoricana, n. sp. Plate 53, fig. 15. 
Shell of medium size, moderately stout, of almost rectilinear outline, translucent, with a narrow 
yellowish or brownish-yellow spiral band around the whorls about one-fourth the breadth of the 
