GASTEROPODA. 77 



Axis, f of an inch. 



Locality. Mam. Crag, Bridlington. 



The specimen figured is from the Museum of the Philosophic Society of York, 

 and was obtained at Bridlington, where, I am informed by Mr. Charlesworth, who 

 sent the specimen, it is not very rare. It much resembles a recent and undescribed 

 species, said by Mr. G. B. Sowerby, sen., to be from the north-west coast of Africa. 



Its distinguishing character is the number of ridges upon the volution. These 

 are placed at regular distances, the lower one projecting a little, which gives the 

 whorl a slight conoidal form ; the lines of growth are rough and imbricated, and 

 most distinct between the ridges, which are somewhat rubbed and rounded. A 

 subquadrangular form of volution gives it an angular edge and a flat base, which 

 has three or four spiral stria? or ridges, the outer ones most prominent, with elevated 

 lines of growth. The columella is nearly straight, with a subcanaliculated base, or 

 everted left lip, bringing this species into close approximation with Cerithium. It 

 is one of those shells by which the two genera might be connected. 



A fragment of a specimen of Turritella from the same locality, apparently a 

 distinct species, was given to me by my friend F. Edwards, Esq., though it is too 

 imperfect for figuring or description. 



Pl'EAMIDELLA,* Lam. 1815. 



Gen. Char. Shell turreted, elongato-pyramidal, generally smooth and glossy, 

 sometimes costated, composed of numerous closely-set volutions ; aperture sub- 

 canaliculated ; columella nearly straight, with several folds or ridges. 



1. Pyrahidelt.a ljiviuscula. S. Wood. Tab. IX, fig. 2, a—b. 



Pyramidella unisulcata (?). Dujardin. Mem. Soc. Geol. de France, t. 11, 1837. 

 Pyramid ella ltf.viuscula. Grateloup. Bord. foss. pi. 7, fig. 79, 80, 1838. 



— terebellata. S. Wood. Catalogue 1842. 



— — Nyst. Coq. foss. de Belg. p. 431, pi. 37, fig. 28, 1844. 



P. Testa elongato-turritd, laevigata, politd, apice obtuse- ; anfractibus 8 — 9 planatis ; 

 suturd sabsidcatd ; aperturd subovatd ; labro acuto, intus dentato ; colicmetld recta; tripfi- 

 catd, plicis incequalibus. 



Shell elongato-turriculate, smooth, and glossy, with an obtuse apex; whorls 

 flat, about nine in number ; suture distinct, deep, subcanaliculated ; aperture 

 subovate ; outer lip sharp, toothed within ; columella straight, slightly replicate, 

 with three unequal folds. 



Axis, i^ of an inch. 



Locality. Cor. Crag, Sutton. 



A very abundant species. This shell appears to be identical with the Belgian 



* Etym. Pyramis, pyramid or spire. 



