Terrestrial Moll u sea from Norfolk Island. 523 



exserted spire; whorls 3, the first very small, the remaining 

 two very rapidly increasing, the last sculptured with very 

 fine, microscopic, closely set, transverse, silky strire ; suture 

 impressed, narrowly margined below; columella margin 

 cuivedly excavated above, very obliquely descending below ; 

 labrum submembranaeeous at the extreme eoVe, advancin«- 

 in front, receding above and below ; aperture very large, 

 ovately subrecf angular. 



Alt. 15*5, diam. map 18 - 75, diam. min. 14 mm. 



Aperture: alt. 12-25, diam. 14 mm. 



Hub. Ball's Bay, Noifolk Island (R. Bell). 



ALLENOCONCHA, gen. nov. (Zonithlr). 



Shell thin, corneous, depressedly turbinate or almost 

 planulate, imperforate, microscopically spirally striate. 

 Genotype: A. basispiralis, Preston. 



Allenoconcha basispiralis, sp. n. 



Shell turbinate, thin, semitransparent, polished, shining, 

 pale reddish brown ; whorls 5, flattish, regularly increasing, 

 the last rather sharply angled at the periphery, marked with 

 radiate growth-plicae, and sculptured with microscopic, closely 

 set, wavy, spiral stme ; suture rather lightly impressed, 

 narrowly margined below ; base of shell convex, sculptured 

 with similar stria? to those on the spire ; columella outwardly 

 expanded, obliquely and rather steeply descending; labrum 

 acute; aperture obliquely, broadly, and compressedly sub- 

 lunate. 



Alt. 2*5, diam. maj. 4*5, diam. min. 4 mm. 



Hob. BalPs Bay, Norfolk Island (R. Bell). 



Allenoconcha belli, sp. n. 



Shell small, depressedly conoid, with somewhat convex 

 base, slightly polished, yellowish brown ; whorls 4, regu- 

 larly increasing, the last angled at the periphery, microscopi- 

 cally sculptured with fine, wavy, closely set, spiral stme ; 

 suture impressed, narrowly margined below; columella 

 margin white, narrowly reflexed throughout, somewhat 

 oblicpue, curved ; labium simple ; aperture very broadly and 

 a little obliquely sublimate. 



Alt. 2, diam. maj. 3*5, diam. min. 3'25 mm. 



Hab. Steel's Point, Norfolk Island (/?. Bell). 



37* 



