134 



that P. bivaricosus, and the other species, herein touched on, do 

 not resemble any of the Bulimi of New Guinea so far as known. 



Placostyhis is not known to occur on Norfolk Island ; and con- 

 sidering the position of the lattei* between New Zealand, Lord 

 Howe Island, and New Caledonia, with the numerical preponder- 

 ance of Placostylus where it is found, we are aiforded further food 

 for reflection on this important subject. 



It is interesting to note that the geological occurrence of P. 

 senilis, Gassies, in the Isle of Pines and Koutoumo Island, New 

 Caledonia, is very similar to that of var. senilis at Lord Howe 

 Island, in a sand-rock overlying an upheaved coral i^eef, and 

 inferior to the present surface soil of the islands.* 



In the course of these investigations I have been assisted with 

 several important suggestions by Messrs. J. Brazier and C. Hedley, 

 which have led up to the views enunciated. 



THE LAND AND FRESH-WATER SHELLS OF LORD 

 HOWE ISLAND. 



By C. Hedley, F.L.S. 

 (Plates xxi. — xxii.) 



In the Memoirs of the Australian Museum, No. 2, " Lord Howe 

 Island," a sketch will be found on pp. 22 - 30 of the moUuscan 

 fauna of the island, illustrated by plates 4 and 5, which were, by 

 an unfortunate accident, reversed. Stress of professional duties 

 has prevented Mr. Brazier from completing this outline by 

 detailed descriptions of the species there enumerated, and, greatly 

 to the disadvantage of conchological science, that portion of the 

 work dealing with fluviatile and terrestrial shells is now under- 

 taken by the present writer. 



On glancing over the species inhabiting the island, the most 

 noticeable feature is that they are all endemic, while the absence 

 of ubiquitous species like the Truncatellit indicate that further 

 search would augment the roll. To the eye of an Australian 

 student the types are unfamiliar, and old acquaintances are 

 conspicuous by theii- absence. Here, the operculates are largely 

 represented, in Australia they arc a foreign intrusive element 

 confined to the north-east border, where they increase with every 

 degree of latitude as Torres Straits are approached. Neither are 



* Gassies, loc. cit., Pt. ii., p. 67. 



