2 ON SOME LAND AND Ai^FATIC SHELLS FROM MARIA ISLAND. 



Woods, but maturer exam])les have a constant and unique flat 

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

 attachment, and by this character it is separated from all 

 known coiifreners. 



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 umbilicatcd, depressed lenticular, of 

 a pale brown colour, finely striated throughout with distant, 

 prominent, oblique riblets, whorls 4, convex al>ove, obtusely 

 carinated at the periphery ; aperture roundly lunate, mar- 

 gins approximating. 



Diara., greatest, 2 ; height, \\ mill. 



Habitat : Maria Island, under and attached to stones. 



This new species is about the size of Helix hobarti, Cox., 

 but differs much in both form and sculpture. Its decided 

 lenticular build, and, for so small a shell, prominent riblets, 

 quite separates it from the large number of minute species 

 of the genus which have been described. 



LIST OF SPECIES COLLECTED. 



Aquatic Species. 



1. Potamopyrgus sirasoniana. Brazier variety, 



2. Ancylus mariae, u. sp. 



Land Species. 



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



2. Bulimus gunnii. Pfr. Very plentiful in favourable 



localities. 



3. Vitrina verreauxi. Pfr. Abundant. 



4. Helix sinclairi. Pfr. Rare; of the usual type. 

 6. ,, ruga. Cox. 



6. ,, legrandi. Cox. 



7. ,, diemenensis. Cox, 



8. ,, halli. Cox, 



9. ,, nelsonensis. Cox. 

 10. ,, juliformis. Cox. 

 31, „ hobarti. Cox. 



12. „ lottah. Mihi. 



13. „ discors, u. sp. 



