Laonui.\ GASTROPODA. 749 



fine crowded spiral lines. Colour corneous, alternately flamed with 

 whitish and reddish-brown above, horny-brown beneath. Epidermis 

 lustrous, translucent. Spire conical, but little higher than the 

 aperture ; outlines very lightly convex. Protoconch of 1J smooth 

 volutions. Whorls 5|, regularly increasing, rather convex ; peri- 

 phery carinated, base very convex. Suture simple, slightly im- 

 pressed. Aperture somewhat oblique, subrhomboidal. Peristome 

 thin, sharp. Outer lip angled. Columella short, arcuate. Inner lip 

 thin, expanded. Umbilicus narrow, open, showing part of the 

 penultimate whorl, deep. 



Diameter Maj., 3-75 mm. ; min., 3 mm. : height, 2-5 mm. 



Animal with the mantle rather anterior, included ; tail acute, 

 without any mucous gland ; peduncles long, slightly clavate, ap- 

 proximated at their bases. Colour greyish-brown, the anterior portion 

 of the head darker ; sometimes a dark transverse band under the 

 shell. (Hutton.) 



Dentition. Button. T.N.Z.I.. xiv, 153. pi. 3, f. F, N. ; pi. 4. f. N 

 (as H. fattia). 



Jaw composed of about 20 imbricating, papillate plates. 



Raduki having the formula 20 + 1 + 20 ; central tooth with a, 

 single cusp and cutting-point ; laterals and marginals bicuspid, the 

 cusps and cutting-points equal, small. 



Type in the Canterbury Museum, Christchurch. 



Hob. North Island : Thames (Adams) ; Ho wick (Major Broun) ; 

 Tuakau ; Wanganui ; Wellington. South Island : Kenepuru ; Ti- 

 muka (Professor Chilton) ; Akaroa (F. Suter) ; Capleston ; Grey- 

 mouth ; Dunedin, type (Hutton) ; Milford Sound ; Owaka ; Fortrose 

 (Miss Eich) ; Invercargill (W. W. Smith) ; The Nuggets, Port Moly- 

 neux (A. Hamilton). Stewart Island : Half-moon Bay (A. Hamilton). 



17. Laoma cognata, Suter, 1909. Plate 29, fig. 18. 



Laoma (Phrixgnathus) cognata, Suter, Subantarct. Islds. N.Zeal., i, 1909, 

 38, pi. 1, f. 16. 



Shell minute, conical, thin, finely costate, keeled, perforated. 

 Sculpture consisting of exceedingly fine equal flexuous radiate riblets, 

 about 50 per millimetre, crossed by fine microscopic spiral strise. 

 Colour yellowish-white, with radial broad and regularly spaced streaks 

 of fulvous ; base uniformly light brown. Epidermis thin, not shining. 

 Spire conical, with a blunt apex, about 1^ times the height of the 

 aperture ; outlines straight. Protoconch comparatively large, globose, 

 of 1| quite smooth and strongly convex whorls. Whorls 5, regularly 

 increasing, convex, the last sharply angled at the periphery ; base 

 convex. Suture deep. Aperture transverse, slightly oblique, sub- 

 rhomboidal, not much excavated by the penultimate whorl. P<ri- 

 stome simple, thin, sharp. Outer lip angled ; basal lip very lightly 



