MOLLUSOA OF THE * CHALLEN&Ba ' EXPEDITION. 375 



above, very faintly aad obtusely angulated above the middle, and 

 contracted below ; the last is slightly ventricose, with a rounded 

 base, produced into a very lop-sided triangular snout. Suture 

 small but distinct, being slightly impressed. Mouth erescentic, 

 pointed above, and prolonged below into a short oblique canal. 

 Outer lip thin and sharp, slightly sinuated above, rounded and 

 prominent in the middle, and retreating along the canal. Inner 

 lip flat above, concave at the base of the pillar, which is straight, 

 longish, conical, and obliquely cut ofi" in front : a thinnish, 

 narrow, sharply-defined pad of glaze extends along the whole 

 length of the lip. Operculum subtriangular, with the apex at 

 the lower inner point, thin but strong, brownish yellow. H. 1"55. 

 B. 0-6. Penultimate whorl, height 0-28. Mouth, height 078 

 breadth 0-33. 



This species greatly resembles Fusus {Sipho) Kroyeri, Moller ; 

 but is smaller, and has a contraction below the suture absent in 

 that, the whorls are less tumid, the longitudinal ribs are much 

 smaller and less curved ; the lines of growth correspond with the 

 ribs instead of cutting obliquely across them ; the spiral sculpture, 

 too, is more raised and less regular. The apex in the ' Challenger ' 

 specimen is somewhat eroded, but is distinctly more cylindrical, 

 the first and second whorls being much more nearly equal than 

 in Moller's species. 



4. Ftjsus (Sipho) calithiscus, n. sp. 



St. 147. Dec. 30, 1873. Lat. 46° 16' S., long. 48° 27' E. Off 

 Marion Island and the Crozets. 1600 fms. Qloligerina-ooze. 

 Bottom temperature 32°-2 F. 



Shell. — Thin, white, tumid, fusiform, with a high scalar spire, 

 and a rounded base prolonged into a short, small-pointed, lop-sided 

 snout. Sculpture. Longitudinals — there are very many close-set 

 lines of growth; the surface of the thin membranaceous epi- 

 dermis is very finely and sharply wrinkled, so as to project in 

 very fine lamellae. Spirals — there are on the upper whorls 7 to 

 8 narrow, rounded threads, parted by wider furrows which are 

 very shallow. The spirals become feebler and sparser on the last 

 whorl, with fainter threads in the intervals. Colour porcellaneous 

 white under the pale yellowish- white epidermis. Spij^e high, 

 blunt, scalar. Apex eroded. Whorls about 6, well rounded, 

 slightly flattened at the top, and a little contracted toward the 

 bottom ; the last is rather tumid. Suture strong and impressed. 



