BY CHAS. T. MUSSON. 889 



My thanks are due to Messrs. Brazier and Hedley forinformation 

 on this subject, freely and kindly given. It is to hoped that these 

 few remarks, together with a list of Australasian records (so far as 

 known) appended below, will cause a little more attention to be 

 paid to our introduced forms of Mollusca, which, although often 

 found to be arrant pests, are like ourselves, making a new home 

 in a country to which their forefathers were strangers. 



List of the Naturalised Land and Fresh-water Mollusca found 



in Australasia. 



LiMNiEA PEREGRA, Miiller, 1773. 



L. Hohartensis, T.-Woods, P.R.S. Tas. 1875. 



An abundant species, ranging throughout Europe, to Siberia, 

 Thibet and Afghanistan. Inhabits sluggish streams, ponds and 

 ditches ; as a rule not so large in fast-running water, but cleaner 

 and more elegant. A great wanderer. 



Tasmania : neighbourhood of Hobart (T.-Woods and W. F. 



Petterd). 



LiMNiEA STAGNALis, Linne, 1758. 



L. Tasmanica, T.-Woods, P.R.S. Tas. 1875. 



Common in Europe ; also found in Siberia and Cashmere. 



Inhabits stagnant water usually. 



Frequently found floating shell downwards on the surface of 

 water ; a favourite habit also of L. pe^^egra, and species of the 

 Bulinus family. 



New Zealand ; Auckland, at the Onehunga Springs ; Christ- 

 church, in the Piver Avon, said to have been introduced inten- 

 tionally as food for trout. 



Tasmania : Hobart (T.-Woods). 



Examples of this form in the Melbourne Museum appear to 

 belong to the variety fragilis. 



Planorbis spirorbis, Miiller, 1774. 



In stagnant water and sluggish streams in every part of Gt. 

 Britain. 



