84 BULLETIN OF THE 



stout; anterior and posterior canals developed; outer lip expanded, sliglitly 

 thickened, aperture rounded. Lon. of shell, 6.5 ; of last wliorl, 1.85 ; of aper- 

 ture, 0.75. Max. lat. of shell, 1.5 ; of last whorl, 1.4 mm. 



Cape San Antonio, 640 fms. 



Owing to the anterior taper, this species has the aspect of a diminutive 

 Cylindrdla or Clausilia. It belongs to the section Mastonia of Hinds. 



Triforis (bigemma Watson var. ?) abruptus n. s. 



Shell short, stout, yellowish white to dark red brown in color, with nine to 

 eleven whorls ; sculpture precisely resembling that of T. bigemma Watson, from 

 which the shell differs in its shorter, stouter, and more abruptly tapered f(jrm ; 

 in having about half the number of whorls ; in the rounded and sculjitured 

 base, upon which are several spiral threads and numerous strong and elevated 

 radiating lines of growth ; the anterior canal is very short and not closed in 

 the specimens examined, the posterior canal indicated by a deep wide notch ; 

 the outer lip patulous and flaring. Lon. of shell, 7.5 ; of last whorl, 2.5 ; of 

 aperture, 1.5. Max. lat. of shell, 2.25; of aperture, 1.25 mm. 



Cape San Antonio, 640 fms. Yucatan Straits, 640 fms. 



It would seem hardly probable that such an extreme disparity of form and 

 number of whorls, as well as size, should exist in one species ; however, since 

 the variability of many of these deep-sea forms in many cases surpasses almost 

 anything recorded from shallow water, I have hesitated to separate this little 

 shell absolutely from Watson's species. 



Triforis triserialis n. s. 



Shell slender, acute, whitish or yellowish, of about fifteen whorls ; nucleus 

 flattened, sharply keeled, white, polished ; first nuclear whorl with two keels, 

 on the third an intercalary thread appears, all of which quickly become sub- 

 equal and uniformly nodulated ; sculpture of three spiral rows of tubercles 

 with their anterior (basal) slopes moderate, but the posterior (spireward) slope 

 nearly perpendiciilar to the axis, so that the tubercles point more or less spire- 

 ward ; the posterior row, just in front of the suture, is a little more prominent 

 than the other two, and so marks the whorls, which are somewhat obliquely 

 coiled ; the tubercles are arranged on the whorls obliquely from right to left, 

 and connected by the representative of the nucdear keels, with the spaces be- 

 tween the spirals deep and narrow, that space in which the suture is contained 

 being only distinguishable from the others by the above-mentioned more 

 prominent spiral ; the suture itself, even with a good glass, is hardly to be 

 made out ; base flattened or in the perfectly mature shell rounded, in the first 

 case with one, in the latter case with three well-marked spiral threads and evi- 

 dent radiating lines of growth ; pillar stout, straight, with a thick solid but 

 small lump of callus on it ; aperture small and narrow ; both canals probably 



