FRESHWATER SHELLS OP AUSTRALIA. 269 



Adams's description was founded on old worn specimens, void 

 of the dark brown epidermis which everywhere covers the sur- 

 face. The operculum is said to be " calcareous, with a vertical 

 submarginal claw " {Tenison-Woods, I. c. p. 71). As far as I can 

 discover, judging from an external view, it appears to be thin, 

 horny, paucispiral, with the nucleus subcentral, but rather towards 

 the base or lower end. 



Lieut. C. E. Beddome, I.N., kindly presented to the British 

 Museum some examples of Tatea Jiuonensis, which, on comparison, 

 prove to be identical with the Diala rnfilabris of A. Adams. 



Genus Htdeobia. 



31. Hydrobia* bttccinoides, Quoy Sf Gaimard. 



Pakidina buccinoides, Quoy ^- Gaim. Voy. Astrolabe, vol. iii. p. 1 "Jb, Atlas 



pi. Iviii. figs. 13-15. 

 Hydrobia buccinoides, Frauenfeld, Verhandl. zool.-botan. Vereins Wien, 



1864, pp. 582 & 665. 

 Sab. " Les marais saumatres du port Weston," New Hol- 

 land. 



32. Hydrobia Pretssii, Fhilippi. 



Paludina Preissii, Ph. Abbild. ii. p. 137, pi. ii- fig- 12. 

 Hydrobia Preissii, Frauenfeld, op. cit. suprd, pp. 637 & ^^1 • 

 Sab. West Australia. 



33. Hydrobia Bbazieri, n. sp. (Plate VII. fig. 21.) 



Shell trochoidal, subrimate, small, brown, coated generally with 

 an earthy deposit, acutely keeled at the periphery. Whorls 5, 

 moderately convex, striated by the lines of growth. Keel on 

 body-whorl prominent, acute, falling just above the suture, and 

 visible upon the upper whorls, obsolete on approaching the aper- 

 ture. Base a little convex. Aperture broadly ovate. Peritreme 

 continuous, a little thickened on the columellar side, and feebly 

 expanded on the labral margin. 



Length 3 millim., diam. 2 ; aperture 1-^ long, 1^ wide. 



Sah. South Grrafton, Clarence Eiver, New Soutli Wales, in a 

 freshwater creek {Brazier). 



This species is well characterized by the sharp prominent keel 

 which encircles the middle of the last volution. It does not, 

 however, extend quite to the aperture, which consequently is not 



* The generic poeition of this and the following nine species will remain in 

 doubt until the animals have been carefully studied. 



