590 GASTROPODA. [Pulmonata, 



hermaphrodite opening by an open or closed groove. Mouth with an 

 upper horny jaw, and with 2 buccal lobes, united above, separate 

 below. Radula broad and long ; teeth numerous, in slightly bent 

 cross-series ; central tooth narrow, tricuspid ; laterals diminishing 

 outwards. 



Shell spiral, with a horny epidermis, the internal partitions often 

 absorbed ; aperture elongate, with strong folds on the inner lip ; 

 the outer lip often dentate. 



These animals usually frequent salt marshes. 



Fossil they appear first in the Jurassic. 



KEY TO GENEKA. 



A. Shell with a periumbilical keel ; columella with 2 plaits . . OPHICAEDELUS. 



B. Shell without a keel on the umbilical area. 



a. Colurnella with 3 plaits, the uppermost very large . . MARINULA. 

 aa. Columella with 2 small plaits, the lower one sometimes 



obsolete, situated on the lower half . . . . LEUCONIA. 



aaa. Columella with 2 strong plaits, situated at the upper 



half . . . . . . . . . . . . CREMNOBATES. 



Genus 1. OPHICARDELUS, Beck, 1837. 



Ophicardelus, Beck, " Index Molluscorum," 1837, 108. Type : Auricula aus- 

 tralis, Q. & G. 



Shell ovato-oblong ; spire elevated, subconic ; aperture oval ; 

 columella with 2 plaits, the lower oblique, the upper horizontal and 

 prolonged exteriorly, forming a periumbilical keel ; outer lip simple, 

 without teeth. 



Distribution. Australasia, New Caledonia, &c. 



1. Ophicardelus australis, Quoy and Gaimard, 1832. Plate 24, 

 fig. 1. 



Auricula australis, Q. & G., Voy. Astrol., ii, 1832, 169, pi. 13, f. 34-38. 

 Ophicardelus australis, Q. & G., Ad. G.R.M., pi. 82, f. 9. Melampus 

 (Ophicardelus} australis, Q. & G., Grit. List, 39. Ophicardelus australis, 

 Q. & G. : Button, J. de Conch., 1878, 42 ; M.N.Z.M., 34 ; Conch. Icon., 

 xx, f. 34. Tralia (Ophicardelus) australis, Q. & G. : Crosse, J. de Conch., 

 xlii, 320. Helampus costellaris, H. and A. Adams, P.Z.S., 1854, 12 ; 

 C.M.M., 57 ; Crit. List, 39 ; Button, J. de Conch., 42. Tralia costellaris, 

 Ad., M.N.Z.M., 33. Cremnobates cornea, Swainson, P.R.S. Tas., 1856, 

 43. Melampus Stutchburyi, Pfeiffer, P.Z.S., 1856, 393. 



Shell ovate-conic, imperforate or rimate, rather solid, smooth or 

 costate, usually with brownish spiral bands. Sculpture consisting of 

 distinct growth-lines, and very often of numerous irregularly spaced 

 and flattish axial ribs, no doubt marking periods of growth ; below 

 the suture there is a more or less distinct narrow groove. Colour 

 yellowish or light brown, with one or several dark-brown spiral bands. 

 Epidermis horny, thin, faintly shining. Spire conical, generally a 

 little less than the height of the aperture ; outlines lightly convex. 

 Protoconch very small, almost always eroded. Whorls 9, flat, the last 



