65 



ON SOME TASMANIAN FEESHWATEE UNIVALVES. 



By the Eev. J. E. Tenison-Woods, F.L.S., E.O.S., Hon. 



Member Eoyal Society, New Soutli Wales ; and Hon. Cor- 

 responding Member Eoyal Societies Tasmania, Victoria ; 

 Adelaide Phil. Society, etc., etc. 



IRead 7th Odoher, 1878.] 



On the 9th August, 1875, I read before this Society a 

 paper on the Freshwater Shells of Tasmania, which was 

 incorporated in the Proceedings, and aj^pears in the volume 

 for 1875, p. 66. In dealing with certain of the univalves, I 

 stated my reasons for regarding them as true Bytliinice, and 

 for not including them in the genus Paludestrina, of 

 D'Orbigny. Since that time I have been able to compare 

 the Tasmanian shells with good types of the European 

 BijtlimcB, and I have come to the conclusion that our shells 

 differ in so many important respects from them that they 

 cannot be considered the same. I do not think, however, 

 that they should lie considered as FaludestriniB. That is a . 

 genus erected for South American shells, characterised 

 thus : — 



Shell semi-globose, thick, solid, with a short obtuse spire, 

 and few smooth whorls ; aperture large, oval, entire; peristome 

 continuous, inner lip callous. . Animal with subulate tentacles, 

 at the external base of which the eyes are situated. The oper- 

 culum is horny, oval, and paucispiral. Small sj^ecies found in 

 fresh or brackish waters in the West Indies or South America."^ 

 (See D'Orbigny. 2Iollusques de Vile de Cuba, 1841, vol. 1., 

 p. 199, and vol. 2., 1842, p. 7 ; also PaJceontologie Franqais, 

 Ter. Cret.). M. Chenu, in his Manuel de GoncJiyliologie, looks 

 upon this genus as synonymous with one proposed by J. K. 

 von Muhlfeldt (J. D. W. Hartmann. Von Hartmannsrutlii. 

 System der Erd und Flusschnechen der Scliweiz. Sticrms Fauna 

 VL, Heft 5., p. 57), the etymology of which was derived from 

 xWos yXvcpw, stone sculpture. It was separated by the authors 

 as a division of Faludina, of which P. naticoides, FerussaCj 

 was the type. Gray, in the FMlosopliical Transactions, 1835, 

 p. 308, unites the genus Lithoglyjjhics with Liitorince ; but 

 Pfeiffer, in 1841, in Weigmann's Arcldfiiv Naturgeschichte 

 (Berlin Arch. 1, p. 228), retains it. Hermannsen, in his 

 Indicis Genera Malacozoorum (Cassel, vol. 1, 1846 ; vol. 2, 

 1847-8), in vol. 2, p. 191, makes the genus Paludestrina a 

 synonym of Hydrohia. The latter was, according to Mons. 

 P. Fischer (Journal de Conchy., 1878. Note sur la synonomie 



* One has teen described from Ne^v Zealand, by M. Crosse. 



