Mr. W. H. Benson on new species 0/ Cyclostoma. 191 



sutnra impressa ; anfractibus 4^ convexis, sensim accrescentibus ; 



apertura circulari, peristomate tenui, recto, marginibus approxi- 



raatis ; imibilico profundo, perspectivo. 

 Operculo comeo, tentii, concaviusculo, arctispirali ; anfractibus 7-8. 

 Diam. major 12, minor 10, alt. 4 mill. 

 Hab. ad DarjUing, Himalajse Sikkimensis. 



With reference to its operculum and aperture it belongs to the 

 third dinsion of Pfeiffer^s Cydophorus. Although the larger 

 of my two specimens does not bear the signs of age, yet, even 

 if the peristome should be found to acquire a further develop- 

 ment, the pecuhar dull and sharp scabrous sculpture, as weU as 

 the narrower umbilicus, will sene to prevent the species from 

 being confounded yath any aUied form, such as C. annulaium 

 and C. stenostoma, which possess a similar operculum. The im- 

 pressed spiral strise are confined to the inner slope of the whorl, 

 towards the sutm-e, and are only \"isible under a lens. C. pla- 

 norbulum, Sow., has a veiy different operculum, and belongs to 

 Aperostoma, Troschel. 



C. stenomphalum, Pfr,, Zeitschr. 1846, and Conch. Cab. 2nd 

 edition, p. 59. t. 8. f, 5, 6, — Pfeiffer notes that the habitat of 

 this species is imknown, but that a smaller bleached specimen 

 occurs in Dr. V. d. Busch's collection, marked " from Bengal." 

 I have recognised this species in a shell sent to me by Dr. Jerdon 

 from the island of Elephanta, near Bombay, where it was found 

 by Brigadier Watson. Petit de la Saussaye, Journal de Con- 

 chyhologie, 1850, marks C. stenomphalum with doubt as a va- 

 riety of C. Indicum, Desh., a species which has been productive of 

 much disagreement among conchologists, e. g. Pfeiffer, Philippi, 

 Sowerby, Mousson, and Petit. Phihppi figm'ed a shell for it 

 which Pfeiffer, Mousson, and Petit agree in considering to be 

 C. oculus Capri. Pfeiffer, however, refers Deshayes' original 

 shell to the same, but Mousson and Petit agree in considering it 

 distinct. Sowerby figured an orange-mouthed shell from the 

 Nilgherries, which I received from Dr. Jerdon, as C. Indicum, 

 and united it with a white-mouthed shell from Ceylon which 

 he had named, in MSS., C. Ceylanicum. Under this name the 

 latter variety is described by Pfeiffer, and figured by Kiister. It 

 is worthy of remark, that Belanger's specimen, described as C. 

 Indicum, by Deshayes, is from the same locality as my large 

 specimen of C stenomphalum. 



With reference to Dr. Von dem Busch's small bleached variety, 

 if the specimen should appear to have been received from Capt. 

 W. J. Bovs, I should have little hesitation in assigning to it 

 the locality of Bhamoui-y, at the foot of the Western Himalaya, 

 on the road leading to Almorah, where a very similar shell was 



