86 BULLETIN OF THE 



This shell somewhat resembles T. concors Hinds, from the Straits of Malacca, 

 but the aperture in our species is much narrower, and the shell is of a different 

 color. The base is also of a somewhat different shape. The specimen meas- 

 ured is the most perfect, but not the largest. 



Triforis colon n. s. 



Shell very slender, elongated, acute, pure white, with a glassy polish when 

 fresh, with twenty-eight or thirty whorls when perfect and complete ; nucleus 

 and first nuclear whorl white, polished, smooth, flattened on top ; surface passing 

 gradually into the second nuclear whorl, with two strong narrow projecting 

 smooth keels, which are then continued into the normal sculpture which they 

 assume very promptly ; the keels project so much that the diameter of the 

 keeled whorl is slightly larger than that of the tubercled third whorl ; spiral 

 sculpture consisting of two rows of round, pointed tubercles and a narrow, flat- 

 tened band on each edge of the whorl ; the latter occasionally a little waved, 

 but usually smooth, one before and one behind the suture joining so closely 

 that the suture is practically invisible, or appears only under a strong magnifier 

 like a faint groove on the joined surfaces of the (really double, but appar- 

 ently single) narrow band ; there are sixteen tubercles on the last turn, and 

 those on the anterior row are opposite the interspaces of the posterior row, 

 thus falling into oblique series from right to left across the whorls ; the bases 

 of the tubercles are connected spirally and transversely by small ridges, and the 

 tubercular rows are much more elevated above the general surface than the 

 BUtural bands ; there is on the flattened base a single faint thread just within 

 the periphery ; a very young specimen, however, shows several additional inner 

 striae ; none of the specimens have the mouth in its adult form, consequently, 

 as in immature specimens of this genus generally, the base is flattened, and 

 the canal short and straight, the pillar without callus, and the outer lip simple, 

 thin, and not projecting ; the transverse sculpture additional to the above is 

 solely composed of the lines of growth, which are hardly evident, except on 

 the base ; outline of the spire a very elongated cone, which in old and decol- 

 lated specimens assumes a Bubcylindrical form. Lon. of shell, 12.0; of last 

 whorl, 1.5 ; of aperture (immature), 0.6. Max. lat. of shell, 1.87 mm. 



Sigsbee, off Havana, in 450 fms. Off Cape San Antonio, in 640 and LOOS 

 fathoms. 



Tins species has a sculpture somewhat like Triforis ruber Hinds, from New 

 Ireland ; bnt the tubercles are alternate instead of opposite, and die form and 

 coloration are qnite distinct. Indeed, they would fall into different sections 

 according to Hind's classification. 



Triforis ibex n. a. 



Shell elongated, conical, but leas deader than T. colon, yellowish white, 

 blunt-tipped, with eighteen or nineteen rather rounded whorls ; nucleus about 



