94 MOLLUSCA FROM THE CRAG. 



This species is not so abundant as S.foliacea, from which it differs in being more 

 elongate, and in tapering gradually, with less fimbriated foliations. The volutions 

 are perfectly smooth, differing in that respect from a recent species in my pos- 

 session, which resembles it in all other respects, but that it is striated ; the Crag 

 shell does not appear ever to have the least vestige of strige, and the peristome is 

 much reflected and turned over, so as to form an obtuse varix, producing a nearly 

 continuous rib up the spire. 



9. Scalaeia clatheatula. Turt. Tab. VIII, fig. 19, a — b. 



Turbo clathratulus. Turt. Linn. vol. iv, p. 500, 1806. 



— Turt. Conchological Dictionary, p. 208, 1819. 



Turbo parvus. Maton and Racket. Trans. Lin. Soc. vol. viii, p. 1/1, pi. 5, fig. 1, 1807. 

 Scalaria minuta. J. Sow. Min. Conch, t. 390, fig. 3-4, 1825. 



— pseudo-scalaris. Dubois de Montp. Foss. de Wolhyn. Pod. p. 43, pi, 11, fig. 36-37, 1831. 



— fulchella (?). Phil. En. Moll. Sic. vol. i, t. 10, fig. 1, 1836. 



— clathratula. S. Wood. Catalogue 1842. 



Sc. Testa turritd lavigafd, imperforatd ; anfractibus, convexis, coutiguis, costellatis ; 

 costellis confer tissimis, amelliformibus ; aperturd subcirculari ; marginibus acutis. 



Shell turreted, smooth, and imperforate, with nine convex, contiguous volutions ; 

 costellse rather variable in number, generally numerous, lamelliform, thin, de- 

 pressed, and reflected ; aperture subcircular, with a thin, reflected, sharp, and 

 elevated margin. 



Axis, f- of an inch. 



Locality. Cor. Crag, Sutton. Recent, British Seas. 



This species is exceedingly abundant and variable in the number of costas ; in 

 some there are upwards of 20, while others have not more than 14 on one volution. 

 It appears to differ from the S. Trevelyana principally in its more elongated form and 

 less reflected costse. I have not yet seen this species from the Red Crag, although 

 a strong shell, and very abundant in the older formation ; in a recent state it is a 

 very rare shell, and may probably be one of the species now dying out. 



10. Scalaeia Teevelyana. Leach, MS. Tab. VIII, fig. 20. 



Scalaria Trevelyana. Winch. Geology of Lindisfarn, An. of Philosophy, xx, p. 434. 



— Treveliana. Thorpe. British Marine Conchology, p. 254, fig. 27, 1844. 



Sc. Testa turritd, elongato-conicd, latiusculd, imperforatd, laevigata ; anfractibus con- 

 vexis, subdisjunctis costellatis ; costis tenuibus, reflexis, crebris, depressis. 



Shell turreted, elongato-conical, imperforate, smooth ; whorls convex, slightly 

 detached ; with numerous depressed costce, thin and slightly reflected, about sixteen 

 on the last volution ; aperture suborbicular. 



Axis, f of an inch. 



Locality. Red Crag, Sutton. Recent, British Seas. 



I have found but one specimen of this shell, which appears to agree so well with 

 a recent individual of S. Trevelyana in my possession, that I am induced to give a 

 figure of it, although it is not perfect. The last six species have the convoluted 



