SuTER. — Oil Netu Zealand Pleurotomidae. 65 



Sub-family PLBUROTOMIN^. 



Operculum oval, with terminal nucleus. 



Genus Pleurotoma, Lamarck (1799). 



Shell turriculated, fusiform ; spire long, sharp ; aperture 

 ovate, columellar margin smooth, the outer lip with a narrow 

 profound sinus situated rather distantly from the suture ; 

 canal long and narrow, straight, open. Dentition, 1 — — 1. 



Pleurotoma ischna, Watson. 



Watson, Journ. Linn. Soc. London, vol. xv., p. 403 

 (1881); "Challenger" Exp. Rep., pt. 42, vol. xv., 

 p. 208, pi. xxii.., fig. 2 (1886). 



Shell high, conical, blunt, with a contracted base and 

 longish snout, little sculpture, strongish, yellowish-grey, 

 porcelaneous. Lines of growth rising into tubercles on the 

 upper whorls. Whorls 7, faintly keeled by a more prominent 

 spiral thread ; another similar close above the suture. Upper 

 whorls reticulated. Mouth club-shaped. Sinus rather deep, 

 open-mouthed. 



Length, 8-5 mm.; breadth, 2-3 mm. 



Tvpe in the British Museum (Nat. Hist.). 



Hab. In 700 fathoms, off East Cape (Stat. 169, Chall. 

 Exp.). 



Genus Genotia, H. and A. Adams, em. 1853 {Genota). 



Shell narrowly obconic, cancellated ; body-whorl gradually 

 tapering to a but slightly developed canal ; lip-sinus wide and 

 shallow ; aperture long and narrow, with subparallel margins. 

 Operculum unguiculate. 



Genotia engonia, Watson. 



Watson, Journ. Linn. Soc. London, vol. xv., p. 405 

 (1881) ; " Challenger " Exp. Eep., pt. 42, vol. xv., 

 p. 300, pi. XX., fig. 7 (1886). 



Shell fusiform, biconical, with a rounded keel angulating 

 the whorls, and a broad lop-sided snout. Lines of growth 

 crossed by close-set spiral threads, somewhat granular below 

 the keel. Colour porcelaneous-white. Whorls 8, with a 

 slightly concave shoulder. Suture slightly canaliculated. 

 Mouth rhomboidally pear-shaped, with a broad open anterior 

 canal. 



Length, 32 mm. ; breadth, 13-2 mm. 



Tvpe in the British Museum (Nat. Hist.). 



Hah. In 700 fathoms, off East Cape (Stat. 169, Chall. 

 Exp.) ; one specimen. Obtained also off Inosima, Japan, in 

 345 fathoms. 



