Gastroptychia.] GASTROPODA. 185 



Fain. DIPLOMMATINID^l. 



Shell small, dextral or sinistral, umbilicated or subperforated ; 

 whorls convex ; aperture subcircular ; peristome usually double, outer 

 lip expanded, columclla sometimes with a spiral fold. Operculum 

 horny or calcareous, concave, of few whorls. 



The metropolis of this family is the Oriental or Palaiotropical 

 region. 



Genus 1. PALAINA, 0. Semper, 1865. 



Type : P. alntri, Semper. 



Suell mostly sinistral. The last whorl is constricted at its beginning 

 or at the last fourth. Aperture without spiral fold. 



1. Palaina chordata, PfeiSer, 1855. 



Diplommntina chordata, Pfr., P.Z.S., 1855, 105; Moil. Pneura. viv.. ii, 12; 

 Medley and Suter, P.L.S. N.S.W. (2), vii, 620; Suter, J. de Conch., 

 xli, 223. 



Shell sinistral, deeply rimated, subfusiform, diaphanous, thin. 

 Sculpture consisting of somewhat distant cord-shaped radiate riblets. 

 Colour waxy-whitish. Epidermis very thin. Spire ovately conical, 

 apex acute. Whorls 7, convex, the last attenuated, ascending an- 

 teriorly. Aperture slightly oblique, subcircular. Peristome double. 

 The outer lip shortly spread out, the inner lip continuous over the 

 parietal wall, shortly adnate, otherwise rather expanded. 



Diameter, 2 mm. ; height, 4 mm. 



Type in the British Museum. 



Hob. New Zealand (Strange, fide Cuming). 



Remark. I have not seen this species, and its occurrence in New 

 Zealand requires confirmation. 



Genus 2. GASTROPTYCHIA, Kobelt and Moellendorff, 1900. 



Gastroptychia, Kobelt and Moellendorff, Nachrichtsblatt d. Deutsch. Mai. 

 Gesellsch., 1900, 186. Type : Paxillus adversus, H. and A. Adams. 

 Paxillus, H. and A. Adams, A.M.N.H. (2), vii, 1851, 63, not of Michean. 



Shell pupiform, rimate, smooth ; spire acuminated ; aperture semi- 

 ovate, ascending on the body-whorl ; inner lip adnate, spreading, 

 flexuous, with a prominent tooth-like fold in the middle ; outer lip 

 double, emarginate anteriorly ; umbilical region with a spiral elevated 

 ridge ending in a notch at the fore part of the aperture; operculum 

 orbicular, of many gradually enlarging whorls ; nucleus central. 



1. Gastroptychia peregrina, Gould, 1847. 



Balea peregrina, Gld., P. Bost. S.N.H., ii, 197; U.S. Expl. Ex., xii, 91, 

 f. 105, n, b. Diplommntina (Paxillus) peregrina, Gld. : Hedley and 

 Suter, P.L.S. N.S.W. (2), vii, 620 ; Suter, J. de Conch., xli, 223. 



Shell small, sinistral, elongated, subfusiform, solid, opaque, rufous- 

 cinereous, hardly striated, perforated. Spire mamillated at the apex. 



