42 M. C. Semper on a new Oenus o/Testacellidas. 



Nl.— On a 7ieio Genus o/" TestaceUidse in Australia. 

 By C. Semper. 



It is a fact often complained of that it is extremely difficult or 

 even impossible to obtain the animals of tropical shells, espe- 

 cially of the land-shells. This, indeed, is to be regretted the 

 more, as even conchologists begin to miderstand that the 

 examination of the animals will furnish many interesting ob- 

 servations, especially valuable for the geography of the species. 

 Very lately I met with an instance which may be worth 

 a short notice. Through the kindness of Herr v. Frauenfeld 

 I obtained two well-preserved specimens of Helix incBqualis, 

 Pfr., which, apparently, is common in Australia, the examina- 

 tion of which proved that I had a genuine Testacellid before 

 The jaw is entirely wanting ; and, as the drawing shows, 



me 



Rhjtida mcequalis, Pfr. 



the teeth of the tongue so completely resemble those of Olan- 

 dina (of which genus I have had occasion to examine three 

 species) that this Australian Helicean must necessarily be 

 ranged close to Glandina. 



In the work of Albers on the Helicidfe this species is placed 

 in the group Rhytida, which is considered there the last sub- 

 genus of those allied to Patula. The type of the subgenus is 

 Helix Greenwoodi of New Zealand, which is nearly related to 

 the Australian species ; however, Helix Strangei^ Pfr., living 

 also in Australia, comes nearer to it. The last species has 

 lately been classified in the genus Zonites by Mousson (Journ. 

 de Conch, ser. 3. vol. ix. p. 36) ; and indeed it cannot be gain- 

 said that both these flati?/??/^?VZa-species possess a Qcxiainhahitus 

 oi Zonites-^ yet Crosse rightly remarks {ibid. p. 57. 1) that it 



