Species of Land- ^foUusca from Borneo. 2-45 



collection tliroii;2:h ^Ir. A. Everett, made in the hills of 

 Borneo by Mr. C. Hose, and I have to thank them both for 

 the further assistance they have thus given to me. We are 

 apparently only beginning to know the richness of the land- 

 molluscan fauna of this great island, so that as it becomes 

 explored in all parts what a wealth of new species we may 

 exj)cct it will produce ! Two shells I now describe present 

 a remarkable ditference from the hitherto known s[)ecics of 

 Opisthostoma from India and the Malay peninsula in being 

 more or less spined, the first and iinest example yet dis- 

 covered being 0. grandespinosa^ in which the spines are 

 developed in a peculiarly beautiful way. The same variation 

 in Borneo extends to the genus Diplommatina, as exemplified 

 in D. spifiosa. Further exploration by naturalists who know 

 how and where to find these minute shells will no doubt 

 bring to light others equally interesting. 



The species of Diplommatina now described was sent to me 

 to examine with other species by Mr. Aldrich, of Cincinnati, 

 U.8.A., to whom a collection of Bornean shells had been sent, 

 and a list of which he gave in a paper published in the 

 Journ. Cincinnati See. Nat. Hist. April 1889, p. 23. This 

 shell he thought might be D. concinna, Adams; but it is not 

 that species, and I have much pleasure in naming it after 

 Mr. Aldrich. 



I take this opportunity of giving drawings (PI. VII. 



figs. 4, 5) of two species described in my paper quoted abo.ve, 



pp. 342, 343, but which were received too late to include in 



the plates which illustrated it ; they are Rhiostoma Ilanjer- 



fordi and iris. 



Opisthostoma pulchellay sp. n. (PI. VII. fig. 1.) 



Shell pyramidal, thin, narrowly perforate ; sculpture, wavy 

 costulation on a smooth surface ; upon the lower whorls this 

 forms the base of sharp, thin, white cirque-like bands standing 

 at right angles to the whorl ; on the penultimate and antepe- 

 nultimate these in the centre are produced into short spines ; 

 they are generally found worn off at an early stage of growth ; 

 colour ochraceous with a golden tinge, nearly white on the free 

 portion of the whorl; spire conical; apex papillate; suture 

 much impressed ; whorls 7 up to the constricted portion, 

 whence the latter part is free and curved outwards from the 

 axis and upwards ; aperture circular ; peristome double, very 

 thin, much expanded, particularly the outer margin. 



Size : major diam. 2'2 ; alt. axis 2"3 millim. 



Locality. Baram district, Borneo [C. Hose). 

 Ann. & Mag. N. Hist. Ser. 6. Vol. vi. IS 



