190 PROCEEDINGS OF THE MALACOLOGICAL SOCIEXT. 



Sah. — Picsing, Upper Sadong, Sarawak. 



Characterised by the peculiar shape of the aperture, which is dis- 

 tinctly channelled at the lower part. 



Opisthostoma Picsingense, n.sp. Fig. 1. 



Testa conica, rimata, rufescens, dextrorsa ; anfractus6 convexi, regu- 

 lariter accrescentes, lamellis numerosis, tetiui^simis, con/ertis, ohliquis, 

 ornati, ultimus ad peripheriam obtuse subangulatus. antice contortus et 

 retrorsus ascendens, infra cristatus ; apertura rotundata, campanulata ; 

 peristoma duplex, pallidum, margine interno continuo, leviter expanse, 

 externo versus spiram fere interrupto, anfract. penultimo contiguo. 

 Longit. 2-3, diam. 2-6 mm. 



Hab. — Picsing, Upper Sadong, Sarawak. 



In this species the last whorl ascends so that the top of the 

 peristome is on a level with the top of the third whorl. There does 

 not appear to be any spiral sculpture. 



