60 MOLLUSCA FROM THE CRAG. 



7. CLAVATULA BRACHYSTOMA. Phil. Tab. VII, fig. 8, 8 a. 



PLEUROTOMA BRACHYSTOMA. Phil. En. Moll. Sic. p. 169, t. 26, fig. 10, 1844. 



Cl. Testa turritd, subulatd, fusiformi; anfractibus converts, superne angulatis ; cos- 

 tatis, cos f is longitudinalibus novem, ad suturam evanescentibus ; striis elevatis transversis, 

 aperturd ovatd, canali brevi ; labro acuto, extus incrassato. 



Shell turreted and tapering ; apex rather obtuse ; whorls convex, slightly angu- 

 lated at the upper part ; costated and striated ; costae 9, aperture ovate, with a short 

 canal ; outer lip sharp, thickened externally. 



Axis, | of an inch. 



Locality. Cor. Crag, Sutton. Recent, Mediterranean. 



This species is by no means rare in the Coralline Crag. It agrees with a recent 

 specimen of brachystoma (obligingly lent me for comparison by Mr. Hanley, and 

 received by that gentleman from M. Philippi), except that the striae appear a little 

 finer. The upper three volutions in the specimen from the Crag are cancellated, and 

 on the third volution there are at least a dozen ribs, whereas on those succeeding it 



1 o 



there are never more than eight or nine. The sinus in our shell is in the angulated 

 part of the volution, giving a slight depression at the upper part of the whorl. 



8. CLAVATULA NEBULA. Mont. Tab. VII, fig. 10. 



MUREX NEBULA. Mont. Test. Brit. p. 267, t. 15, fig. 6, 1803. 



PLEUROTOMA BERTRANDI. Phil. En. Moll. Sic. vol. i, p. 198, t. 11, fig. 20, 1836. 



Fusus (?) NEBULA. S. Wood. Catalogue 1842. 



Fusus NEBULA. Thorpe. Brit. Mar. Conch, p. 203, fig. 93, 1844. 



PLEUROTOMA GINNANNIANUM. Phil. En. Moll. Sic. vol. ii, p. 168, tab. 26, fig. 6, 1844. 



MANGILIA NEBULA. Lovtn. Ind. Moll. Scand. p. 13, 1846. 



Cl. Testa turritd, elongatd, subulatd; anfractibus 7 8, convexis, longitudinaliter 

 costnlatis, transversim striatis ; canali breviusculd recta; labro haud incrassato. 



Shell elongate, tapering, with an acuminated spire ; volutions 7 8, convex ; suture 

 deep, spirally striated, and longitudinally costated ; costae 10 11; aperture ovate; 

 outer lip sharp, with a small sinus a little below the suture ; canal very short and open. 



Axis, I of an inch. 



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



I have as yet seen this species from one locality only, where it is not very rare. 

 It appears to differ slightly from Philippi's figure and description. My specimens are 

 most of them much rubbed, though in some the striae are distinctly visible ; Philippi's 

 figures have fewer ribs. The proportions of the aperture are variable, though generally 

 about one third the length of the shell. Loven considers the M. nebula of British authors 

 as identical with the Ginnannianum of Philippi, and I have therefore, upon his authority, 

 retained the name originally given in my Catalogue, although the Crag specimens 

 correspond better with the Mediterranean shell, and are larger than any recent British 

 specimens I have seen. 



