70 



stream running into the Derwent near Duurobin. — U. 

 Maddock. 



AxcYLi^s TASMAXiciJs. n.s. A. Usta parva, ohlongo-ovata,diap}iana^ 

 cornea, con-centrico striata, et suhtillisime rugoso-radiata, epidermide 

 nigro plus minusve induta et macnlata, apice ohtuso, poatico ; apertura 

 postice suhatenuata. 



Shell small, ovate, diaphanous horny, concentrically striate 

 and very faintly rugosely radiate, more or less covered aud 

 spotted with a black epidermis, apex obtuse, posterior aperture 

 subattenuate posteriorly. Long., 3 — 3|. Lat., li — 2, Alt., 

 l|-2. 



Common near Hobart Town in streams, on stems of water- 

 cress (I^asturfium officinale^) 



LIMN^EA. Lamarck, 1799. 



Testa oblonga, interdum turrita; spira exserta, apertura Integra, 

 longitudinalis. Lahrum actUum, infernS ad sinistram reverters et 

 uscendens, in columdlaiu versus aperturam decurrit, plicamque obli- 

 quam mentitur. Operculum nullum. Hist. Nat. des Anim. s. 

 Verteb. 2 edit par Desliayes et Milne Edwards. Paris, 1838. 



Shell oblong, sometimes turretted, spire exsert. Aperture 

 entire, longitudinal. Outer ]\\> acute returning to the left, 

 and ascending decurrent with the columella towards the 

 aperture making a false oblique plait. No operculum. 



The Limneae are world-wide in their distribution, and in- 

 habit ponds, lakes, and running water. The species have a 

 wide distribution, so that it is difficult to distinguish between 

 those foifnd in America and Europe. Sowerby says that the 

 Australian species have generally an inflated form, while 

 Lovell Reeve (Land aud Freshw. Moll of Brit, p. 155) says, 

 " In India, neighbourhood of Calcutta, the shell is cylindi'ically 

 oblong. In Malayan Islands and Punjaub districts of India 

 it is of a peculiarly silvery horny substance, marked with 

 opaque white brown streaks. Western Asia, north of the 

 Himalayas, over the whole of Europe, extending to Greenland, 

 and over all the United States, the Limnese produce a dull 

 horny malleated shell. The inland waters of Central America 

 and Australia have few Limnese. They are chiefly inhabited 

 by Physse. 



1. LiMN^A TASMAJsricA n.s. P.testatemd,pelhicida,eleganterpyrami- 

 data, corneo-fulva ; S2)ira elevata, acuminata, apertura lungitudine, 

 paulo superanti ; anfractibus (5-8) obliquis ; ultimo anfracto inflate ; 

 apertura late ovata ; labio externo tenuissimo, fragilis ; lahio interno 

 subexpanso, plica iiiconspicua, columella alba, vix contorta. 



P. shell thin, pellucid, elegantly pyramidal, horny fulvous ; 

 spire elevated acuminated, aperture little larger than the 



