Terrestrial Mollusca from Norfolk Island. 531 



regularly increasing, the last channelled above and carinate 

 at the periphery, the apical whorls smooth, the later whorls 

 marked with irregular transverse growth-ridges, and sculp- 

 tured with very distinct, closely set, spiral strife ; suture 

 narrowly callously margined above, deeply channelled below, 

 the sutural channel being continued as the supraperipheral 

 channel on the last whorl ; base of shell inflated, bearing the 

 same sculpture as on the spire ; columella margin descending 

 in a very oblique curve; labruin acute, notched at the 

 termination of the supraperipheral channel ; aperture 

 obliquely sublimate. 



Alt. *75, diam. maj. 2, diam. min. 1*75 mm. 



IJab. Limestone quarry , Norfolk Island; also found on 

 Mount Pitt {E. Bell). 



Iredaleoeoncha caloraphe, sp. n. 



Shell rather depressedly turbinate, brown ; whorls 5, regu- 

 larly increasing, the last narrowly channelled above and 

 carinate at the periphery, sculptured with fine, closely set, 

 spiral striae, and marked with oblique transverse growth- 

 piiese ; suture channelled, bearing an erect callous ridge 

 above, bordered on the upper side by a rather deep but very 

 narrow groove; base of shell inflated, also sculptured with 

 line revolving striae ; columella margin vertically descending- 

 tor a short distance, then sharply angled and very obliquely 

 descending below ; labrum acute, notched at the termination 

 of the supraperipheral channel ; aperture broadly and 

 obliquely subcrescentic. 



Alt. 2, diam. maj. 4"25 (nearly), diam. min. 3*75 mm. 



Hab. JDuncombe Bay, Norfolk Island {E. Bell). 



PlTTOCONCHA, gen. nov. (Zonitidce). 



Shell imperforate, corneous, turbinate, swollen, peripherally 

 carinate, spirally striate, and transversely costulate. 

 Genotype: B. concinna, Preston. 



Bittoconcha concbina, sp. n. 



Shell small, turbinate, with inflated spire, thin, horny, 

 dark blackish brown; whorls 4, regularly increasing, the last 

 strongly carinate at the periphery, sculptured with coarse, 

 closely set, very oblique, and somewhat curved, transverse 

 pliese, crossed by indistinct spiral striae, which are more 

 noticeable on the apical whorls and base of the shell ; suture 

 impressed; base of shell inflated; columella margin white, 



