SuTER. — On N.Z. Land and FresJi-icatcr Shells. 227 



thirds of the diameter, not descending, on the inner side 

 rapidly ascending, regularly arcuated to the periphery. Suture 

 very deep. Aperture lunar, narrow, vertical, much excavated 

 by the penultimate whorl. Peristome straight, acute ; upper 

 margin narrowly, lower broader arcuated ; columellar margin 

 vertically descending, margins convergent. Penultimate whorl 

 smooth, white, rather callous. Umbilicus broad, deep, per- 

 spective, about one-third of the diameter. 



Diameter, 0-lin. (2-7mm.) ; height, 0-04in. (l-5mm.). 



Hah. Under rotten logs. Very scarce ; only two specimens. 

 North Island : Forty-mile Bush ; Hastwell. (H. S.) 



Named in honour of Professor F. W. Hutton, F.G.S., 

 to whom I am so greatly indebted for his assistance in con- 

 chology. 



DiplompJialus moussoni, n. sp. Plate XV., fig. 12, a, h. 



Shell small, discoidal, white banded with brown, the 

 streaks following the direction of the ribs at irregular dis- 

 tances, faintly shining, thin, transparent, strongly ribbed ; ribs 

 sliarp, directed forwards and arcuated on the surface, slightly 

 undulating on the periphery, straight below, about 18 ribs in 

 the tenth of an inch (7 per mm.). Spire concave to about 

 one-quarter of the height. Apex smooth, shining. Whorls 4, 

 the first 3 very narrow, the last large, two-thirds of the dia- 

 meter, not descending, on the inner side rapidly ascending, 

 regularly arcuated outside. Suture vei-y deep. Aperture ver- 

 tical, lunar, excavated by the penultimate whorl. Peristome 

 straight, acute, lower margin regularly arcuated, the upper 

 margin forming a nmch narrower arch : columellar margin 

 descending nearly vertically, not reflected; margins convergent. 

 Penultimate whorl smooth, white, somewhat callous to a short 

 distance outside the aperture. Umbilicus broad, perspective, 

 about one-quarter of the diameter. 



Diameter, 0-15in. (4mm.) ; height, 0-08in. (2mm.). 



Hab. Under rotten logs. Only two specimens. North 

 Island : Forty-mile Bush ; Hastwell. (H. S.) 



Named in honour of Professor A. Mousson, of Ziirich, the 

 distinguished conchologist, who has assisted me in any way he 

 could for the last twenty years. 



Hyalina microrctlculata, n. sp. Plate XV., fig. 13, a, h. 



Shell very small, globosely elevated, horny-fulvous, shining, 

 very thin, pellucid, finely striated, reticulated between the 

 striae. Sj)ire conical, elevated. Whorls 5, rounded, regularly 

 increasing. Suture impressed. Aperture oblique, rotundly 

 lunar, but little excavated by the penultimate whorl. Peri- 

 stome straight, acute, margins faintly convergent ; columellar 



