CAMPTOCERAS. — CAMPTONYX. 465 



measure 2-4xl'o iniii. One of these lias the second whorl 

 solute. 



I found a series of twelve specimens from the original locality 

 in the British Museum, presented in 1909 by the late W. T. 

 Blanford. The largest of these only measures 3-5x2 mm., and 

 is therefore smaller than the type. 



The species is included in Camptoceras with some doubt, it 

 differs considerably in several characters from the other two 

 known species. Benson himself had some misgivings on the 

 subject. I do not, however, think it advisable, without anatomical 

 data to guide us, to establish a separate genus. 



Genus CAMPTONYX, Benson. 



C(tmpto7iyx, Benson, A. M. N, II. ser. 3, i, 1858, p. 336, pi. 12, 

 tigs. 1-t) (shell and animal), fip:. 7 (jaw and radula) ; Stabile, 

 Atti Soc. Sci. Nat. Milano, vii, 1864, p. 122 ; Nevill, Hand List, 

 i, 1878, p. 21o: Blanford, J. A. S. B. xlix, 1880, p. 200, footnote ; 

 Fischer, Man. Conchyl. 1883, p. 502 ; Tate, in Woodward, Man. 

 Moll, appendix, 1890, p. 43; Cooke, Cambridge Nat. Hist, iii, 

 1895, pp. 302, 438. 



Type, C. theobaldi, Benson. 



Bange : India. 



Shell pileiform, obliquely conical, reddish brown; apex sub- 

 spiral, free, obliquely incurved, tuimed towards the right side ; 

 whorls Ig, the last almost constituting the entire shell ; a dorsal 

 rib, resembling an obtuse subspiral keel and corresponding in- 

 teriorly to a siphonal furrow, runs from the apex to the right 

 margin ; aperture large, symmetrical, regularly ovate, margins 

 expanded. 



Fischer in 1858 * united Camptonyx with Vahnciennesia, a 

 genus of fossil species occurring in Miocene beds in the Crimea, 

 Turkey, Koumania, Croatia, vSlavonia, and Hungary, but subse- 

 quently in his " Manuel " he modified his views so far as to 

 separate the two, although still regarding them as closely allied. 

 With all due deference to so eminent an authority, I am unable 

 to concur in his view, for, although undoubtedly having some 

 features in common, the mere fact of C'amjHow/.v being furnished 

 Avith a spirally convoluted apex, while Valenciennesia has a non- 

 spiral apex, apart from the enormous difference in size, militates 

 against the assumption of close affinity. 



4G2. Camptonyx theobaldi, Benson. 



Camptonyx theobaldi, Benson, A. M. N. II. ser. 3, i, 1858, p. 336, 

 pi. 12, figs. 1-6 (shell and animal), fig. 7 (jaw and radula); 

 Adams, Gen. Rec. Moll, ii, 1858, p. 644, pi. 138, fig. 10 ; Ilanley 



* Joiu-n. Concbyl. vii, 1858, p. 316. 



2h 



