354 THE VOYAGE OF H.M.S. CHALLENGER. 



conical. Apex consists of 4 very small, conical, scarcely convex, buff whorls, the upper 

 part of which bears straight little bars, and the lower part is minutely reticulated ; below 

 the buff-coloured surface the shell is porcellauous. Whorls 9 in all, slightly straight and 

 sloping below the suture, convexly rounded above, cylindrical below ; the last is a little 

 tumid, with a rounded base produced into a short, broad, lop-sided snout. Suture very 

 slight, as the inferior whorl laps up on the one above it, but it is defined by the curve of 

 the whorls. Mouth oval, pointed above ; there is scarcely any canal below. Outer lip 

 very thin, a little contracted above, and patulous below ; its curve is somewhat flattened 

 about the periphery ; its edge forms a very regular curve with a slight shoulder above, 

 between which and the body lies the broad, shallow, rounded sinus. Inner lip is a thin 

 narrow glaze which very soon dies out on the oblique, twisted, fine edge of the short 

 conical pillar, beyond whose point the front of the shell advances a good deal : the 

 junction of the pillar and the body is concave. H. 0'46 in. B. 0"22. Penultimate 

 whorl, height O'll. Mouth, height 0-24, breadth (HI. 



This species slightly resembles Daphnclla supercostata, E. A. Sm., but is more obese, the mouth is 

 shorter, the edge of the sinus is not thickened, and the apex is sharp and sculptured, while in that 

 it is plain and blunt. It most resembles perhaps Pleurotoma translucida, Wats. ; but that is smooth, 

 and has a blunt rounded apex. 



8. Clathurella pudens (Watson), (PI. XIX. fig. 2). 



Pleurotoma (Defrancia) pudens, Watson, Prelim. Report, pt. 10, Journ. Linn. Soc. Lond., vol xv. 



p. 461. 



Station 24. March 25, 1873. Lat. 18° 38' 30" N., long. 65° 5' 30" W. North of 

 Culebra Island, West Indies. 390 fathoms. Pteropod ooze. 



Shell. — Small, oblong, white, smooth, with a high, subscalar, small, and sharp-pointed 

 apex, a short and scarcely swollen body-whorl, and a conical base produced into a broadish, 

 triangular, lop-sided snout. Sculpture: Longitudinals — besides hair-like lines of growth, 

 there are some faint, very oblique, upwardly convex folds, which are obsolete on the 

 earlier and on the last whorls. Spirals — the surface is covered with superficial rounded 

 threads which, obsolete in the sinus-area, are feeble on the body, but sharper and more 

 distinct on the base and snout. There is a very faint angulation below the sinus-area. 

 Colour : the shell is thin, semi-transparent white, with hardly any gloss. Spire conical, 

 subscalar from the slight short tumidity below the suture.- Apex consists of 4 embryonic 

 whorls, which are buff, darkening to orange at the tip ; they are a little broadly conical, 

 rounded, with a slight angulation, and parted by a distinct suture ; they rise to a very minute, 

 spirally scratched, round, and very slightly prominent knob ; they are sculptured with 

 raised bars, which are straight and simple above, but oblique and crossed below. Wliorls 

 7^ in all ; they are slightly concave and shouldered in the sinus-area, which is bordered 



