458 SUCCIKEIDjE. 



reaching nearly to the lower margin of the tooth, the side cusps 

 being subobsolete. The lateral teeth are like the centrals but 

 unsymmetrical. The marginal teeth are about as wide as high, 

 with one stout, pointed inner cusp, and two short side cusps." 



The genus is confined to Central India, and only two species are 

 known. Although Blanford only regarded it as a subgenus of 

 Succinea, I consider, apart from the totally different build of the 

 shell, the presence of an internal furrow for a siphon sufficient 

 warrant to rank it as a separate genus, as was done by Fischer. 



457. Lithotis rupicola, Blanford. 



Succinea (Lithotis} rupicola, Blanford, A. M. N. H. ser. 3, xii, 

 1863, p. 186, pi. 4, figs. 8-10 j Nevill, Hand List, i, 1878, 

 p. 214. 



Succinea rupicola, Pfeiffer, Novit. Conch, ser. 1, iv, 1871, p. 11, 

 pi. 112, figs. 1-4 ; ibid., Hon. Helic. Viv. vii, 1876, p. 35. 



Lithotis rupicola, Bland & Binney, Ann. Lye. Nat. Hist. New 

 York, x, 1874, p. 349 (jaw and lingual dentition, description) ; 

 Binney, Proc. Acad. Nat. Sci. Philadelphia, 1874, p. 54, pi. 5, 

 figs. 3-6 (jaw and lingual dentition, figures) ; Hanley & Theo- 

 bald, Conch. Ind. 1874, pi. 81, fig. 7 ; Pfeiffer & Clessin, Nomencl. 

 Helic. Viv. 1881, p. 231; Tryon, Struct. Syst. Conch, iii, 1884, 

 p. 88, pi. 100, fig. 40. 



Original description : " Testa ovata, pertenuis, succinea, cur- 

 vate costulato-striata ; spira plana, sutura vix depressa ; anfracti- 

 bus 1J, ultimo prope aperturam descendente ; carina ex apice 

 oriens, spiralis, peristomatis ad marginem dextrum, 2 mm. a 

 sutura, desinens ; apertura perinagna, ovata, continua, intus 

 politissima, nitida ; peristomate tenue, rectum, margine columel- 

 lari callose appresso. 



" Diam. maj. 7 mill., min. 5, alt. 2|." (Blanford.} 



Hob. India : Western Grhats ; Khandala (Blanford}. 



" Combines the characters of Camptonyx and Otina, belonging 

 to the Auricidacea, with those of Succinea and its allies. From 

 the shell alone, which has the form of Otina, with the substance, 

 texture, and peculiar external ridge and internal furrow of Camp- 

 tonyx, I should have supposed the present species to belong to the 

 last named genus ; but the retractile eye-bearing peduncles prove 

 its place to be in the neighbourhood of Succinea, from which 

 genus the internal furrow for a siphon distinguishes it as a well- 

 marked subgenus. Tentacles are extremely small and rudimentary 

 in several of the subgenera of Succinea, and, in the present case, 

 appear to be wanting ; if present, they are certainly very incon- 

 spicuous. The animal of Helisiga, Less.*, as represented in Adams, 

 Gen. Eec. Moll. pi. 73, closely resembles that of Lithotis, but has 

 a larger foot, while the shell only differs in the absence of the 

 siphonal furrow. 

 " Lithotis abounds adhering to the precipitous basaltic rocks of the 



