64 COXTRIBL'TIOXS FOR SYSTEMATIC CATALOGUE AQUATIC SHELLS. 



I have tliouglit it well to reproduce the orii,'iual descrip- 

 tions of several obscure Tasmauiau aquatic shells that were 

 published iu the proceedings of the Vienna Society of Zoology 

 and Botiny many years ago from specimens sent to Europe 

 by the late Mr. Konald Gunn, and also of one collected in the 

 island b}- Professor Braun. These extracts I consider of 

 very great vahie and interest, as they no doubt will have an 

 im])ortant influence upon the nomenclature of the subject 

 and furthermore open quite a new and imexpected field 

 for careful investigation — later on I will endeavour to 

 identify the species described by the various authors. I may 

 state that the AmptiUaria Tasmania', Lc Guillon (Revue 

 Zool. page 105, 1842) is no doubt the shell now known as 

 belonging to the more modern genus Ampliihola, which is 

 generally considered as more fittingly placed in the marine 

 molluscan fauna. I have to thank Mr. John Brazier, F.L.S., 

 for the arduous task of supplying .ae with exact copies of 

 the descriptions taken from the extre'uely rare scientific pub- 

 lications in which they aj^pear, and to Mr. Thureau, P.Gr.S., 

 I am indebted for the kind and cheerful manner in which 

 he undertook to give me literal translations. 



So far as investigation has gone very few of our species 

 have been found to be identical with those known to exist in 

 the mainland of Australia, although a very large amount of 

 practical work has been done since the publication of the 

 catalogue of the fresh water shells of this island by the Rev. 

 Teuison-Woods (Proc. Royal Soc. Tas., 1875) ; more recently we 

 have had the useful reference summary of Professor Ralph 

 Tate and Mr. John Brazier, entitled "Check List of the Fresh- 

 water Shells of Australia " (Pro. Linnean Society of N.S.W., 

 1881), the elaborate and beautifully illustrated catalogue by 

 Mr. Edgar A. Smith of the British Museum (" On the 

 Fresh-water Shells of Australia," Journal of the Linnean 

 Society, London, 1882), and many valuable and ini])ortant 

 jiajiers by several well-known S2)ccialist8 all materially 

 enhancing our knowledge of this comparatively neglected de- 

 jiartment of natural history. In Australia the cosmopolitan 

 genus Pliysd is very largely re] >resented, for of thisgroup al)ove 

 50 species have been recorded of which number only two or 

 three have the faices of our insular forms. Limnoca has 16 

 species, one of which is certainly, and another doubtfully, 

 id<'iitical with forms common here, riinwrbis \s represented 

 by but six kinds, all different from thosi? known to exist iu 

 our streams. The genus Unio has about, 1 7 species to our 

 peculiar one which is restricted iu habitat to northern rivers. 

 In the l?i7/(ynia-group only six si)ecies are quotc<l ; here wo 

 have a much larger number. Only one form of Ancylus has 

 been discovered to (jur four — the two giants of the genus 

 have no congeners in the mainland. The northern form of 



