12 



0^^ SOME LAND AND FRESH-WATER MOLLUSCA FROM SUMATRA. 

 PART I. 



By the Eev. R. Ashington Bullen, B.A., F.L.S., F.G.S. 



Bead lOth November, 1905. 



PLATE II. 



The shells recorded in this communication have been collected during 

 the Spring and Summer months of 1905 in various localities in mid- 

 Sumatra, and reached me during July and August. A further series 

 will arrive later and be dealt with in a future paper. 



The sequence followed in this paper is that adopted by Dr. E. von 

 Martens in Max Weber's " Zoologische Ergebnisse einer Reise in 

 Niederlandisch Ost-lndien," Band ii (1892), pp. 209-264, and Band iv, 

 Heft 1 (1897), pp. 1-331. 



CroLOPHORUs (Crossopoma) planorbulum, Lamarck. 

 Ifab. — Mount Sago. 



CrcLOPHORUs (Amplus) eximius, Mousson. 

 Jlab. — Mount Sago. 

 Dark variety. 



Var. RouTERi, n.var. PI. II, Figs. 1, 2. 



Testa subdepresse turbinata, permodice umbilicata, subsolida, superne 

 spiraliter multum subelevate striata, ad peripheriam subcarinata, infra 

 striis etiam multis spiralibus paullum elevatis, sculpta ; periostracum 

 ornaraento et subfusco et castaneo stictum, infra f uscatum ; anfractus 5, 

 tres priores convexi, apicem satis promiuentem formantes, duo sequentes 

 subconvexi ; sutura leviter impressa ; apertura caeruleo-albida, rotun- 

 data, oblique descendens ; peristoma angustum, subcrassum, expansum, 

 vix reflexum, caeruleo-albidum, margine columellari late expanso et 

 reflexo, umbilicum plus minus obtegente ; operculum corneum, multi- 

 spirale. Diam. max. 50, min. 41 mm. ; alt. 40*5 mm. 



ITab. — Mount Singalong. 



These specimens are somewhat like, but smaller than, typical 

 C. eximius, the shell being more closely whorled, the columella being 

 regularly widened so as almost to cover the umbilicus ; the body-whorl 

 is also more rotund and the spiral ridges are more rounded, and there 

 are more of them on the under-surface of the body-whorl. In one 

 specimen of C. eximius from Mount Sago there is a widening of the 

 columella, but it is not symmetrical as in the form under discussion, 

 and is more in the nature of an abnormality than a regular widening. 

 The new shell differs in many essentials from C. validus, Sow., and 

 its varieties from the Philippines, and C. appendiculatus, Pfr. The 

 above description is put forward as provisional. M. Henri Rouyer has 



