1 39 



NOTES ON THE NON-MARINE MOLLUSCA OF NORFOLK AND 

 PHILLIP ISLANDS, WITH DESCRIPTIONS OF NEW SPECIES. 



By E. R. Sikes, B.A., F.L.S., etc. 



Read 8th June, 1900. 



PLATE XIII. 



Some little while ago I received from Mr. Suter a shell collected 

 on Norfolk Island, with a request that I would undertake its 

 determination. This led to an examination of the shells in the 

 British Museum, where I found a fairly representative collection 

 formed by John Macgillivray during a voyage of the " Herald," and 

 presented by the Admiralty. The description of this collection is the 

 aim of the present paper. One or two obscure species, and also some 

 single specimens, still await determination, in the hope of further 

 material coming to hand. 



Thanks to the kinduess of Mr. Hedley, I am enabled to incorporate 

 drawings made by him of species very briefly described by Cox and 

 hitherto unfigured ; I am glad to have this opportunity of further 

 expressing my indebtedness to Mr. Hedley for much information on 

 the subject. 



As pointed out by Professor Tate and others, the faunal relation- 

 ship of Norfolk Island lies rather with New Zealand and Lord Howe 

 Island than with the Australian Continent. 



1. Microcystis nux, n.sp. PI. XIII, Figs. 4 and 5. 



Testa subperforata, compacte conica, solidiuscula, cornea, sub lentc 

 lineis incrementi notata, nitida ; anfractus 5-5^, plano-convexi, lente 

 regulariterque creseentes, ultimus constrictus, antice non descendens, 

 in regione umbilicali valde sed anguste excavatus ; apertura lunaris, 

 marginibus callo tenui junctis, dextro acuto, columellari leviter reflexo, 

 incrassatulo. Alt. 4, diam. max. 7 mm. 



Sab. — Norfolk Island, under dead leaves (coll. Brit. Mus.). 



A small, compactly coiled species, the last whorl constricted in 

 front, with a well-marked depression in the umbilical region ; tin; 

 mouth is slightly thickened within by a white callus, thus causing 

 a lighter- coloured patch to appear behind the outer lip. 



2. Microcystis castaneocincta, n.sp. PI. XIII, Pigs. 8 and 9. 



Testa depresso-conica, solidiuscula, sub lente lineis incrementi notata, 

 microscopice et inconspicue dense spiraliter striata, nitida, cornea, 

 supra et subter peripheriam fascia lata fusco-castanea cincta; anfractus 

 5i, plano-convexi, regulariter lenteque creseentes, ultimus in regione 

 umbilicali excavatus, sutura leviter impressa ; apertura lunaris, 

 marginibus callo tenui junctis, dextro acuto, columellari leviter 

 reflexo, incrassatulo. Alt. o 9, diam. max. 7 8 mm. 



Sab. — Norfolk Island, under dead leaves (coll. Brit. Mus). 



