2 ON SOME LAND AND AQUATIC SHELLS FROM MARIA ISLAND. 



Woods, but maturer examples have a constant and unique flat 

 expansion of the aperture, which thus forms a firm base of 

 attachment, and by this character it is separat<id from all 

 known cojigeiiers. 



So far as known, it is restricted to the insular locality 

 mentioned. It is apparently abundant, and was the only 

 species collected on the island. 



2. Helix discors, n. sp. 



Shell minute, openly umbilicated, depressed lenticular, of 

 a pale brown colour, finely striated throughout with distant, 

 prominent, oblique riblets, whorls 4, convex above, obtusely 

 carinated at the periphery ; apertui'e roundly lunate, mar- 

 gins approximating. 



Diam., greatest, 2 ; height, 1| mill. 



Habitat : Maria Island, under and attached to stones. 



This new sj^ecies is about the size of Helix hobarti, Cox., 

 but differs much in both form and sculpture. Its decided 

 lenticuLu- build, and, for so small a shidl, prominent riblets, 

 quite separates ir, from the large number of minute sjjecies 

 of the genus which have been described. 



LIST OF SPECIES COLLECTED. 



Aquatic Spenes. 



1. Potamopyrgus simsoniana. Brazier variety, 



2. Ancylus marise, n. sp. 



liand Species, 



1 Bulimus dufresnii. Leach. Abundant, but not large. 



2. Bulimus gunnii. Pfr. Very plentiful in favourable 



localities. 



