M0LLUSCA OF THE ' CHALLENGER ' EXPEDITION. 4G9 



four embryonic whorls, which form a high cone with a slightly 

 impressed suture, and rise to a small rounded prominent tip : 

 the sculpture is typical, the tip being scored with some 10 or 

 12 minute sharp spiral threads, while the other whorls have 

 straight bars on the upper part and reticulated bars below, only 

 the part occujned by the straight bars is exceptionally short. 

 Whorls 7-8, of regular increase, with a drooping shoulder, a 

 double carination, and a marked contraction to the inferior 

 suture ; the last whorl is very regular in form, with a slightly con- 

 tracted base, from which projects a small triangular one-sided 

 snout. Suture slightly impressed, flatly but minutely margi- 

 nated below. Mouth oval, angulated above, and prolonged into 

 a rather broad and longish canal below. Outer lip very regu- 

 larly curved, but drawn out straight along the canal : its edge, 

 which is rather prominently curved below, forms a somewhat low 

 shoulder above, between which and the body lies the wide-mouthed, 

 deep, rounded sinus. Inner lip rather broad and distinct ; it is 

 very early cut off on the short pillar at the very oblique twisted 

 edge, which then runs on as a thin sharp margin to the canal : 

 the junction of the pillar and body is rather deeply concave. 

 II. 0-15. B. 06. Penultimate whorl, height 0026. Mouth, 

 height 0-06, breadth 003. 



This is a very small species ; but I think one of the speci- 

 mens is very nearly full-grown. 



60. Pleurotoma (Defrancia ?) perparya, n. sp. 



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

 Pernambuco. 350 fms. Mud. 



Shell. — Small, high and narrow, ribbed and spiralled, with 

 convex whorls, a small short body, impressed suture, a high, 

 conical, scalar, small-tipped spire, a rounded base, and a small, 

 short, triangular, one-sided snout. Sculpture. Longitudinals — 

 there are on the last whorl 12, on the earlier one or two fewer, 

 small, straight, rounded ribs, which originate somewhat promi- 

 nently in an angle of the whorls below the sinus-area, and run 

 down to the point of the base, but do not extend to the snout ; 

 they are parted by rounded furrows of nearly three times their 

 width : close below the sinus is a crowded row of very short, 

 small, curved bars — the old sinus-scars. The whole surface is 

 closely, very regularly, and rather sharply scored with lines of 



