40 1 



(MIC of which roaches a lent^tli of i - Mill., the i^cmmatc keel is from lindy i^ciiiniatc tc) nearly 

 smooth in lower whorls, and may approat'h ihc specimens menlioned by Smiiii in i(;<).i (I. c.j 

 as var. minor, in ilu> u[)i)im' poslnuclear whorls the gemmulcs are more constant. 'The nuclear 

 whorls, about .( in number, arc^ at I'lrst smooth, then over a lari^er or small(M- part costnlat(.', 

 with more or less conspicuous traces of a narrow, undulated keel, just above; the sutures (this 

 nucleus remembers the section Gcuinutla). The specimens vary slightly in colour, some of them 

 being- lighter, I think onl)- in part b)- being bleached. 



10. riciti'otoDia (Heniiplenrotoi)ia) violacea Hinds. 



Hinds. Voy. "Sulphur", iAIolI., p. i6, PL 5, fig. 8. 



RI':eve. Conch. Ic. Vol. I, Pleurotonia, fig. i86. 



WeiNKAUFI^ IMartini-Chcmn. Conch. Cab. Ed. II, Vol. IV, p. 30, Tl. 6, fig, 7, 9. 



Tryon. Man. of Conch. Vol. VI, p. 169, PI. 4, fig. 42. 



Stat, 33. Bay of Pidjot, Lombok. 22 M. and less. Mud, coral and coralsand. 3 Spec. 



Stat. 51. Madura-bay. 69 — 91 M. Fine grey sand, coarse sand with shells and stones. 5 Spec. 



Stat. 58. Seba, Savu. Up to 27 M. Sand, i Spec. 



Stat. 71. Makassar and surroundings. Up to 32 M. Mud, sand with mud, coral. 2 Spec. 



Stat. 95. 5°43'.5 N., ii9°4o'E. Sulu-archipelago. 522 M. i Spec. 



Stat. 1 14. Kwandang-bay-entrance. 75 M. Hard sand very fine. 4 Spec. 



Stat. 231. Amboina, 54 M. Coralsand. i Spec. 



Stat. 285. South coast of Timor. 34 M. Limit between mud and coral. Lithothamnion. i Spec. 



The specimen from Stat. 58 has on the top of the lirae a fine brown line; this specimen 

 is uncommonly well preserved, it may be that the species in all its splendour, will be always 

 marked in the same manner, but that this colour is commonly rubbed off. The specimen from 

 Stat. 95, from the exceptional depth of 522 M. is a young worn shell and may not have lived 

 at this depth. 



1 1 . PleiLvotoma (Hemipleurotonia) vertebrata Smith. 



Smith. Ann. and Mag. Nat. Hist. Ser. 4, Vol. XV, 1875, p. 416. 



Smith. Proc. Zool. Soc. Lond. 1879, p. 186, PI. 19, fig. 6, 6a. 



Tryon. Man. of Conch. Vol. VI, p. 170; PL 3, fig. 29, 29^: [violacea pars?). 



Stat. 51. Madura-bay. 69 — 91 M. Fine grey sand, coarse sand with shells, i Spec. 



The specimen is small, about 6 Mill. ; it probably would be broader, even than Smith's 

 fig. 6, if adult ; the species has been considered by many authors as synonymous wdth or as a 

 variety of P. violacea Hinds, the Siboga-specimen, which has been identified by its author, 

 seems to differ sufficiently from young specimens of violacea^ being much less slender, even 

 though it appears to be slightly variable in this respect. The sculpture appears also to differ con- 

 siderably, but the only specimen is too small, to be fit for close comparison. 



12. Pleztrotoma (HemipleiLrotoma) sp. 



Stat. 260. Near South point of Nuhu Jaan, Kei-islands. 90 M. Sand, coral and shells, i Spec. 



This specimen is probably young and certainly too bad for description, it belongs to 

 the same alliance as the two preceding species. 



37 



