184 NOTES ON BRITISH MOLLUSCAN DISTRIBUTION. 



The above was written at the close of last year ; and 

 although a large number of specimens have been examined 

 during the three months which have since elapsed, we think it 

 well to allow the figures to stand as given in the original M.S. 



BIBLIOGRAPHY. 



A Monograph of the Land Shells of Tasmania. 



—By W. F. Petterd. 



Since the publication of Dr. Cox's Monograph of Austra- 

 lian Land Shells, in which only 21 species are noticed as in- 

 habiting Tasmania, the knowledge of the subject has been 

 greatly augmented, principally by Mr. Legrand (who a few years 

 ago published his " Collections for a Monograph of Tasmanian 

 Land Shells," which embraced not only the known species, but 

 contained descriptions of a number of new forms not previously 

 published), and Mr. Brazier (who has described a number of 

 species in the ' Proceedings of the Zoological Society of 

 London '). 



More extended observations show that much confusion has 

 occurred by variations of the different forms having been re- 

 garded and recorded as distinct species. 



Mr. Petterd in his excellent work has rendered good 

 service to conchology by pointing out where the so-called species 

 have been varieties only of some previously known kind. The 

 distribution of the different species is fully given and the 

 synonymy compiled with evident care and accuracy. The total 

 number of land shells found on the island appears to be 79, 

 of which number Dr. Cox has described 26, Brazier 14, Tenison- 

 Woods 4, Beddome 3, Pfeiffer 6, the Author 17, and the 

 remainder are attributable to various English and foreign con- 

 chologists. 



Two species are introduced European forms : Zonites 

 cella7'ius and Helix piilchella ; and two large and conspicuous 

 species, Helix bisulcata and Helix subangulata, though labelled 



J.C, iv;, April, 1884. 



