Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/571

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1870.] TATE — GLOUCESTERSHIRE LIAS. 405


whorls five, convex, flattened above ; the suture is channelled with an abrupt margin around the upper whorls, and linear around the lower ones ; surface ornamented with numerous incised longitudinal lines and closely set striae of growth, visible by the aid of a lens ; base flat ; umbilicus moderately wide, exposing all the inner whorls.

The shell of this species has great resemblance to that of Cryptoenia heliciniformis, Deslong., but it has more whorls in proportion to its size, and the outer margin of the last whorl is regularly rounded and not subcarinated. The absence of a fissural band, however, removes it from that species. Prom Turbo Marcousanus, Dumortier, it differs in its much more depressed spire, and by its ornamentation.

Locality. " Zone of Ammonites Jamesoni," Leckhampton Road, Cheltenham.

Cerithium ibex, nov. sp. (Pl. XXVI. fig. 8.)

Shell turreted; whorls ten in a length of 7/10 inch, smooth or slightly wrinkled transversely, angulated and imbricating; upper suture bordered by a thick rounded encircling rib.

Dimensions. Length 0.6 inch ; breadth of last whorl 0.2 inch.

C. ibex has the general outline of a Turritella ; but the aperture of a specimen in Dr. Holl's collection justifies the generic position I have assigned to the species. It is most nearly related to G. sidoe, D'Orbigny, Prodr. i. p. 215, which is described in the following terms : — " lisse avec une legere saillie, dans le sens de l'enroulement, au tiers superieur de chaque tour. Sinemurien, Augy-sur-Aubois (Cher)." An examination of the type specimen of G. sidoe enables me to add a character omitted by the describer, and which distinguishes it from C. ibex, that is, an encircling rib below the carina, whereas in C. ibex the encircling rib is above the carina and bounds the upper suture.

Locality. Zone of Ammonites Jamesoni, Cheltenham (R. T.). I have examined specimens collected near Cheltenham by Dr. Holl, and near Gloucester by Mr. J. Jones (coll. Gloucester Mus.).

TORNATELLA CAPRICORNI, NOV. Sp. (Pl. XXVI. fig. 18).

Shell elliptical, spire elongated, apex mamillated; whorls five, scalariform; shoulder of whorl forming a right angle, obtusely rimmed ; last whorl slightly impressed below the upper angle, longitudinally striated, and marked with fine curved lines of growth ; aperture oval, very acute behind and subangular in front ; outer lip thin ; columella with a longitudinal fold.

Length 0.55 inch ; last whorl about 6/10 the length of the shell.

Locality. Zone of Ammonites Jamesoni, Aston Magna (T. Slatter). Zone of Am. capricornus, Mickleton Tunnel (G. E. Gavey).

7. ACTAEONINA CANARIENSIS, nOV. Sp.

Shell elliptical, spire elongated ; whorls four, scalariform ; angle of suture obtuse, margined ; surface of shell shining, marked by