REPOKT ON THE GASTEROPODA. 369 



Shell. — High, narrow, bicouical, with a tall bluut spire, a slightly impressed suture, 

 and a shortish base : the whorls are feebly ribbed and very obsoletely spiralled. Sculp- 

 ture: there are on the earlier whorls about 12, on the last two whorls about 14 elongated 

 tubercles, which project bluntly and slightly above the middle of the whorls, and are 

 obliquely and feebly produced to the inferior suture ; they are obsolete on the base : the 

 surface is closely scratched with fine, somewhat unequal lines of growth. Spirals — there 

 is a very slight pad which forms an inferior margin to the suture ; below this is a hardly 

 concave furrow, on the lower side of which the whorls are angulated by the projection of 

 the tubercles : the lower part of the whorls is very obsoletely marked with broad flat spiral 

 threads, which may be traced to the tip of the snout. Colour pale waxy white, whence 

 the name. Spire conical, with profile-lines interrupted by the prominence of the keel, 

 from which both above and below is a contraction into the suture. Apex consists of 2 

 tumid rounded whorls of nearly equal size, with a very slight suture. Whorls 8 iu all, of 

 slow and regular increase ; the last is small, with a rouuded couical base and a smallish 

 snout: they are angularly convex, with a slight contraction into the suture, both at top 

 and bottom of the whorls. Suture a little impressed, rather oblique. Mouth small and 

 narrow, pear-shaped, scarcely angulated above, and drawn out into a rather narrow canal 

 in front. Outer lip regularly curved above, flat in front : the edge retires slightly below 

 the suture, so as to form the deep rather narrow sinus, whose lower side is made by the 

 very high and prominent shoulder, which advances very far forward, and still continues 

 to do so, though more slightly, on to the edge of the canal, where it again retires. 

 Inner lip: there is a thin glaze on the body and pillar, whose union is very slightly 

 concave : the generic fold is a prominent, rounded, narrow thread which coils round the 

 pillar about the middle and parallel to the suture : the front of the pillar is narrow, 

 twisted, and oblique. H. 0*5 in. B. 0'2. Penultimate whorl, height 0"08. Mouth, 

 height 0-23, breadth 0-09. 



It is interesting to add a new species, and that from the Atlantic, to the few living Pacific species 

 of this Tertiary fossil genus. The whole aspect of the shell is that of a Pleurotoma of the Surcula 

 group. 



2. Borsonia silicea, Watson (PI. XXI. fig. 8). 



Pleurotoma (Borsonia) silicea, Watson, Prelim. Report, pt. 10, Journ. Linn. Soc. Lond., vol. xv. p. 474. 



Station 122. September 10, 1873. Lat. 9° 5' S., long. 34° 50' W. Off Pernambuco. 

 350 fathoms. Red mud. 



Shell. — High, narrow, biconical, with a tall, blunt, scalar spire, and a short contracted 

 base : whorls angulated but hardly prominent above, tubercled but scarcely ribbed, 

 obsoletely spiralled. Sculpture : there are in the middle of the whorls small rounded 



(ZOOL. CHALL. ESP. PART XLII. 188?.) Tt 47 



