PROSOBRANCHIATA. 233 



centric lines more numerous ; and in some specimens from Cuise-Lamotte, in my 

 cabinet, the spire is also much elevated, the shell relatively narrower, and the concen- 

 tric lines close-set, slender, and regular. In the English specimens the relative height 

 of the spire and the character of the concentric lineation agree with those of the 

 specimens from Compiegne ; but the shell is wider, and the margins of the whorls 

 are not so much depressed. These differences, however, attributable probably to local 

 conditions only, do not suggest a doubt of the correctness of the identification. 



Size. — Axis, rather more than 5-6ths of an inch (11 millim.) ; diameter, 3-12ths of 

 an inch (rather more than 6 millim.). 



Localities. — Clarendon Hill. French — Compiegne (fide Desk.) ; Cuise-Lamotte, 

 Trosly-Breuil (fide Graves) ; Laon (fide Mettev.) MM. Deshayes and D'Orbigny also 

 give Parnes ; but M. Graves speaks with doubt of that locality. 



No. 157. Pleurotoma terebralis, Lamarck, var. Tab. XXVII, figs. 10 a — k. 



Pleurotoma terebralis, Lam/c. 1804. Anra. du Muse'e, vol iii, p. 266, No. 20. 



— — Id. 1822. Hist, nat., &c, vol. vii, p. 101, No. 25. 



— — De Blainv. 1826. Diet, des sci. nat., vol. xli, p. 391. 



Besh. 1832. End. meth. (Vers.), vol. iii, p. 799, No. 21. 



— lb. 1824-1837. Desc. des coq., &c, vol. ii, p. 455, t. 62, 



figs. 14—16. 



Var. 1st. ditropis; fig. 10a. P. testa parvuld, elongate!, fusiformi, angustd, turritd, 

 lineis spiralibus eleganiissime granulatis ornatd ; spird elevatd, acuminata ; anfractibus 

 bicarinatis ; marginibus posticis depressis, concavis, ad suturam granidatis, cateris lavibus, 

 vel tenuissime plicatis ; carina posticd acuta, denticulatd ; carina anticd fascioli-formi, 

 denticulato-plicatd ; lineis spiralibus plus minusve distantibus, incequalibus ; ultimo an/ractu 

 antice valde attenuato in canali longo exeunti ; sinu lato, fere semicirculari, in margine 

 collocato. 



Var. 2d. concinna; fig. 10^, k. Testa parvd, bicarinatd, lineis spiralibus perceque 

 granulatis, undique, etiam in marginibus anfractuum, ornatd ; carina anticd granulatd; 

 lineis spiralibus numerosis. 



Var. 3d. gyrata ; fig. 10 £, d. Testa bicarinatd; carinis fascioli-formibus, crassis, 

 oblique plicato-denticulatis ; lineis spiralibus inaqualibus, granulosis. 



Var. 4th. pulcherrima ; fig. 10 e. Testa parvd, bicarinatd ; carina posticd denti- 

 culatd ; carina anticd rotundatd, lavi ; lineis spiralibus elevatis, rotundatis, simplicibus vel 

 obsolete granulatis, supra canalem con/ertis, cieteris distantibus. 



Var. 5th. revoluta; fig. 10/. Testa bicarinatd ; marginibus posticis anfractuum 

 ad suturam lavissime crenulatis ; carina posticd acuta, obsolete plicato-denticidatd, superne 

 revoluta ; carina anticd lineisque spiralibus granulatis. 



