40 BULLETIN OF THE 



then irregularly striated) are produced in a more or less irregular manner, 

 become confluent, and assume the shape of the coral upon which the animal 

 lives. Diam. of embryonic shell, 0.37 mm ; of adolescent, 2.5 ; of adult, 5.0 mm. 

 Lon. of adult, from 3.0 to 9.0 mm. 



Barbados, Hassler Exp., 100 fms. Off Havana, Sigsbee, 450 fms. Yucatan 

 Strait, 640 fms. 



This seems sufficiently different from any species noticed by me. 



Margarita aegleis Watson. 



Linn. Soc. Journ., XIV., 1879, p. 704 ; St. Thomas, W. I., 390 fms. 

 M. lamcllosa Verrill and Smith, Am. Journ. Sci., Nov. 1880, p. 397. 



This beautiful species, like most of the genus, is exceedingly variable, the um- 

 bilicus varying from very wide to comparatively narrow, the shell depressed 

 or conical ; the number of nodulated ribs or simple carinas, the thickening or 

 absence of it on the pillar, and the number of whorls, differing according to 

 age and individual. I am not at all sure that others of Watson's species 

 shoidd not be combined with this ; but, in the absence of specimens for com- 

 parison, I hesitate to do more than suggest a careful inspection. The number 

 examined shows every transition. 



Station 2,805 fms. ; Yucatan Strait, 640 fms.; Station 21, 287 fms. ; Sta- 

 tion 46, 888 fms.; off Cape San Antonio, 640 fms. ; Station 41, 860 Jins. ; Sta- 

 tion 19, 310 fms. 



Margarita asperrima n. s. 



Shell conical, yellowish white, turreted, higher than wide ; whorls five to 

 seven, the last forming half the height of the shell ; base rounded, umbilicus 

 small, partly covered by the reflexed lip, transversely striate, with one longi- 

 tudinal thread close to the bounding nodulated strong carina! rib ; upper 

 whorls with two strong longitudinal ribs, the lower of which forms the carina 

 of the last whorl ; near the beginning of the latter a single less conspicuous 

 thread is intercalated between these two ; the carina is above the middle of 

 the last whorl, and between it and the bounding rib of the umbilicus are four 

 strong, simple revolving threads, not nodulated, between which, near the 

 mouth, intercalary, weaker threads begin to appear. Suture distinct, compact, 

 not channelled, except by projection of the ribs above and below it which 

 rive tin- shell a turreted appearance. Lip thin or slightly thickened, denticu- 

 lated on the edge by the rib-ends ; pillar little thickened, its base apparently 

 toothed by the ends of tin- umbilical threads (these denticulations an- probably 

 missing in tin- perfect adult); mouth slightly oblique, not produced below; 

 transverse sculpture consisting of threads Following the lines of growth, rising 

 into lamella between the ribs, and in passing over them (excepl the basal 

 ones) forming squarish projections, t-utt in^ tin' ribs obliquely. Nucleus smooth, 

 polished, the remainder dull white, with no visiUe nacre. Alt. 7.5. hat. «'l 

 . 6.0. Beight of aperture, 3.0 mm. 



