PROSOBRANCHIATA. 311 
No. 237. Prevroroma tursipa. Solander. Tab. XXXII, fig. 2, a—c. 
Murex rurpipus. Sol. 1766. Brand., Foss. Hanton, p. 19, fig. 31. 
PLEUROTOMA coLon. Sow. 1816. Min. Con., vol. ii, p. 106, t. 146, f. 7, 8. 
— caTaPHRACTA. Morr. 1843. Cat. Brit. Foss. (Ist Edit.), p. 157; (non Broce.) 
— coton. Morr. 1843. Cat. Brit. Foss. (1st Edit.), p. 157. 
— TuRBIDA. Morr. 1843. Cat. Brit. Foss. (Ist Edit.), p. 157. 
— coLon. Bronn, 1848. Index Paleont., p. 1003. 
— TURBIDA. Bronn, 1848. Index Paleont., p. 1011. 
_ coton. D’Orb. 1852. Prod. de Paleont., 25° Etage, p. 359, No. 409. 
— TURBIDUS. D’Orb. 1852. Prod. de Paléont., 25. Etage, p. 359, No. 413. 
— coton. Morr. 1854. Cat. Brit. Foss., p. 269. 
— TURBIDA. Morr. 1854. Cat. Brit. Foss., p. 270. 
Nec. Pxiuvroroma TuRBIDA. Lam. Encycl. Méthod., t. 451, f. 8. 
Nec. = — Lam. Anim. sans Vert., vol. vii, p. 97, No. 5. 
Nec. — coLon. Desh. 1824-37. Coq. foss., &c., de Paris, vol. ii, p. 492, t. 66, f. 4, 7. 
Nec. — —  WNyst, 1835. Rech. coq. foss. d’Anvers, p. 28, No. 26. 
Nec. _ — Wyst, 1836. Rech. coq. foss. de Hoesselt, &c., p. 30, No. 78. 
Nec. _ — De Kon. 1837. Coq. foss. de Basele, &c. p. 20, No. 19. 
Nee. — TuRBIDA. Nyst, 1843. Coq., &c., foss. de Belg., p. 513, t. 40, f. 8. 
Nec. — —= Grat. 1847, Conch. foss., &c., de l’Adour, Atlas, t. 3, No. 21, f. 26. 
P. testa oblonga, sub-fusiformi, turritd, undique concentrice lincald: spird elevati, 
obtusa: anfractibus depresso-convexis ad humeros in juventd carinam obtusam crenatam 
transversim sulcatam, gerentibus, deinde curvo-plicatis; marginibus posticis concavis, ad 
suturam scabro-plicatis et duabus vel tribus lineis elevatis, acutis, cinctis ; ultimo anfractu 
sub-conico ; lineis concentricis supra margines et humeros anfractuum confertis, exilissimis, 
sub-aqualibus ; supra medias partes nonnullis crassis, prominentibus, fastigiiformibus, dis- 
tantibus, ceterum exilibus ; omnino sub-clathratis: aperturd elongato-ovali, in canali bre- 
vissimo, ad basin profunde emarginato, exeunte ; labro tenui, sub-semicirculari ; columella 
contortd, callosd, cristata ; sinu latiusculo, profundo, marginibus sub-parallelis, ad humerum 
collocato. 
Var. B testa anfractibus ad humeros fortiter tuberculatis ; lineis concentricis medianis 
et anticis sub-denticulatis. 
Shell oblong, sub-fusiform, turreted, concentrically ridged and lined ; spire rather 
thick, pointed, and much elevated, forming nearly 3-5th parts of the entire length. 
The whorls, nine or ten without the pullus, are depressedly convex ; in the young state 
they present round the shoulders an obscure, obtuse keel, bearing a closely set series 
of narrow, vertical, slightly curved tubercles, defined at each end, and occasionally 
also traversed by fine, raised, thread-like lines ; these tubercles and the keel gradually 
become less prominent as the shell enlarges, and frequently altogether disappear 
on the last two or three whorls, which then present only a series of numerous very 
fine, thread-like, curved plications, formed by the successive, rounded extremities of 
