192 EOCENE MOLLUSCA. 



Nee Conus deperditus, Brocc. 1814. Conch. Foss. Sub-app., vol. ii, p. 592, No. 10, t. 3, fig. 2. 



nee — — Bors. 1821. Oritt. Piem., p. 14, No. 13. 



nee — — Brongn. 1823. Terr, tert., &c, du Vicentin, p. 32. 



nee — — Bast. 182,). Desc. des coq. foss., &c., de Bord., p. 39. 



nee — — Bronn. 1831. Italiens tertiargeb., p. 12, No. 5. 



nee — — Pusch. 1837. Polens Palaeont., p. 115, No. 2. 



nee — Grat. 1838. Cat. zool., &c., de la Gironde, p. 47, No. 422. 



nee — lb. 1838. Tabl. statist. &c., de l'Adour, t. 19, No. 22. 



nee — lb. 1840. Conchyl. foss., &c, de l'Adour, t. 2, figs. 18, 19. 



nee — Sismon. 1847. Synop. method., &c., Pedem. Foss., p. 44. 



nee — — Sow. 1850. Dixon's Geol., &c., of Sussex, p. 108, t. 8, fig. 9. 



C. testa turbinatd, elongatd, lavi, ad basin transversim obsolete sulcata ; spird promi- 

 nuld, acutiuseuld: anfractibus numerosis, angustis, angulatis, marginibus posticis depressis, 

 strias tenues concentricas gerentibus ; ultimo anfractu regulariter conoideo, sursum dilatato : 

 aperturd angustd ; labro tenui, simplici, valde arcuato, postice profunde emarginato. 



Shell oblong, turbinate, with a moderately elevated mucronate spire, variable in 

 height, but rarely exceeding a fourth part of the whole length of the shell, and ter- 

 minating in a smooth, conical pullus, formed of three volutions ; whorls numerous 

 (10 — 12, exclusive of the pullus), bluntly angulated at the shoulders, nearly straight 

 on the sides, with the posterior margins depressed, narrow, somewhat concave, and 

 concentrically lined ; the concentric lines are usually four or five in number, sharp, 

 irregular, unequal, separated by moderately deep, rounded furrows, and frequently 

 decussated by the lines of growth. In some specimens the early whorls are very 

 finely tuberculated on the shoulders, and concentrically sulcated ; the tubercles, how- 

 ever, disappear after the third or fourth volution, and the shoulders are afterwards 

 smooth and simple : the concentric furrows also become gradually effaced on the 

 posterior portion of the whorls as the shell approaches maturity, and ultimately are 

 altogether lost, leaving only a few very obscure waved furrows traversing the base of 

 the shell. The last whorl is conical, much attenuated in front, with nearly straight 

 sides ; the aperture is linear and narrow ; the outer lip, which is thin, sharp-edged and 

 much arched, presents a shallow but wide curvature at the posterior extremity. 



M. Deshayes states that traces of the natural colouring are sometimes found in the 

 French shells, consisting of narrow, transverse bands, occasionally interrupted by 

 irregular, zigzag patches, following the direction of the lines of growth. Similar traces 

 appear, though very rarely, in the English specimens. 



This species appears to be confined to the middle eocene strata ; for the shells 

 from Ronca (Vicent), described by Brongniart as C. deperditus, D'Orbigny regards as 

 belonging to a distinct species, which he has named C. Brongniartii, and to this species 

 the shells described by Bellardi from the nummulitic beds at Nice, probably are also 

 referrible. Subsequent comparison has shown that specific differences also exist in 

 the various shells from the more recent deposits which have been referred to the 



