THE RECENT MOLLUSCA OF TASMANIA. 



By Mary Lodder. 



Tasmania may be considered fairly rich in recent mol- 

 luscan species, as she possesses nearly 700 marine fornjs, 

 with about 100 terrestrial and fresh-water kinds besides. 

 Very many o* ■^e species in all branches are extremely 

 small, requiring much careful search in order to obtain 

 them, and microscopical examination to reveal their char- 

 acteristics, their beauties of form, sculpture, and coloui-ing. 

 But siich work is well repaid by the results^ whilst, doubt- 

 less, there are still various species to be discovered in the 

 less well-known parts of the island, for many of the recog- 

 nised forms are very local in their habitats, and, in 

 numeroiis cases, their minuteness renders them so difficult 

 to find that even an experienced collector niay overlook 

 them. On the other hand, some of the marine species 

 afford a strong contrast by the great size to which they at- 

 tain, the most remarkable being Valuta mamilla (Gray), 

 which is a foot long when full grown, and broad in propor- 

 tion ; but adult specimens are rarely found in good preserva- 

 tion. The young examples are much prettier as regards 

 colour and markings, having brown bands and dashes on a 

 creamy-yellow ground externally, .while the interior is of a 

 rich yellow, and highly enamelled ; the large mamillary 

 nucleus (which was thought to be a deformity in the first 

 specimen discovered) is always a striking characteristic, 

 giving a curious appearance to the very young shells. This 

 species is chiefly found on the North Coast, where V. fusi- 

 formis (Swainson) and V. tmdulata (Lamarck), with the 

 rarer V . papillosa (Swainson) are also to be had. 



Megalatractus maximus (Tiyon) is another fine shell, also 

 somewhat scarce in perfect condition. The finest specimen 

 I have seen was in the collection of the late Mr. C. E. Bed- 

 dome, who dredged it in the Derwent; it measured 7|- 

 inches in length, and 2| inches in breadth. Triton spen- 

 gleri (Chemnitz) attains a length of 5 inches, its solid struc- 

 ture and thick varices making it a weighty shell. Gyprcm 

 umbilicata (Sowerby) is another remarkable shell found on 



