428 EEV. E. BOOG WATSON ON THE 



umbilical furrow. Operculum typical, having the nucleus apical 

 and being curved ; thin, rather strongly marked with the lines 

 of growth, and having on its outer face a small, prominent, but 

 not thickened bank or rising in the middle from end to end. 

 H. 1-42. B. 0-45. Penultimate whorl, height 0-23. Mouth, 

 height 0-6, breadth 0'24. 



The specimen of this fine species obtained from off Albany 

 Island is full-grown, and is very markedly broader than the other ; 

 but in all obher respects they are identical. Otherwise like P. 

 interrupta, Lam., in form, it has a longer pillar. It has some 

 resemblance in shape to P. rosaria, Eeeve, but in all details is 

 most distinct. 



29. Pleueotoma (Ceassispiea) climacota, n. sp. (fc\t/iaau- 

 tos, scalar). 



St. 172, July 22, 1874. Lat. 20° 58' S., long. 175° 9' W. 

 Inside the reef, Tongatabu. 18 fms. Coral. 



Shell. — Strong, biconical, with a high, pointed spire, and a short, 

 lop-sided, but truly conical base, reticulated with ribs and spirals, 

 and with a constricted band below the suture. Sculpture. Lon- 

 gitudinals — there are about 15 or 16 rather narrow, sharpish ribs 

 on each whorl, with intervening furrows of rather greater 

 breadth ; they cross the whorls with very little obliquity from 

 suture to suture, and on the last extend to the very point ; a few 

 of them bifurcate on the base ; the lines of growth are very 

 slight. Spirals — below the suture is a band about -^ of an inch 

 high, which constricts the upper part of the whorl to the breadth 

 of the base of the one above ; this forms the sinus-area : below 

 this is a shoulder on which the ribs project. There are about 

 sixteen or seventeen rounded spiral threads, which are feeble in 

 the furrows, but rise into small rounded tubercles on the ribs 

 they are parted by shallow flat furrows of about the same breadth 

 of these spiral threads there are four on the penultimate whorl 

 and they diminish in number up the spire. The whole surface is 

 very finely spirally striated ; and there are microscopic granula- 

 tions besides. Colour white. Spire very regularly conical, but 

 distinctly scalar from the angular projection of the shoulder. 

 Apex somewhat worn, but small, apparently consisting of two 

 conical, rounded, embryonic whorls with a fine sharp suture. 

 Whorls 10 in all, rather high, of very regular and slow increase, 

 angulated by the constriction and the shoulder below it. The 



