336 GASTEROPODA OF THE INFERIOR OOLITE. 
anterior extremity of the aperture, thus producing a somewhat Naticoid aspect. It 
may have been the above peculiarity which induced Phillips to regard this species 
as a Natica. 
Pl. XXVIII, figs. lla,11b. Variety from the Pea-grit of Crickley, almost 
identical with Nerita ovata, Romer (‘ Nordd. Oolith.,’ p. 156, pl. x, fig. 6). 
Specimens are a little larger than those from the Dogger, and are somewhat more 
transversely ovate. The callus on the inner lip is subconvex, thus bringing the 
shell within the definition of Nevidomus. The colour markings, often well 
preserved, are suggestive of Neritina; cf. also Neritina Cooksonii, Desl. 
Relations and Distribution.—In addition to the above a few small shells, about 
the size of buckshot, occur in the Lincolnshire Limestone both at Weldon and at 
Ponton, and also more rarely in the Cotteswolds. Because they are small they are 
sometimes named Nerita “ pulla.” They are probably micromorphs of N. tumidula, 
which is the representative on this horizon of N. ovata, Rém., if not absolutely 
identical. A small species in the Great Oolite of Minchinhampton, described by 
Morris and Lycett (‘Grt. Ool. Moll.,’ p. 58, pl. xi, figs. 19, 19a) as Nerita 
minuta, Sow., may be ranked in the same category. 
269. Nerira (Nerimomus), transverse species. Plate XL, figs. 9 a, 9 b. 
Description : 
Height : : . : 12°6 mm. 
Width : ; : : 14°3 mm. 
Shell transversely ovate, tumid, moderately thick ; spire low, occupying about 
one-tenth the height of the entire shell, and formed of about two and a half whorls 
widely separated by the suture, which is canaliculate at the junction with the 
body-whorl. This is extremely ventricose, only slightly flattened posteriorly, and 
sloping.. Aperture large, with a thin hemispherical outer lip, whilst there is a very 
wide and convex (Nevidomus) callus on the columellar lip, the margin of which is 
nearly straight and not denticulated. Colour markings are often well preserved ; 
these resemble the markings shown on P].XXVIII, fig. 11 a. 
Relations and Distribution.—Throughout the various horizons in the Oolitic 
rocks we distinguish an ovate and also a transverse form of Nerite. Such a 
transverse form as the one figured in Pl. XL is met with sparingly in the Oolite 
Mar! horizon of the Cotteswolds, and also in the Dogger at Blue Wyke. Itis more 
transverse than Neritina Cooksonii, Desl., yet not precisely like the Nerita trans- 
versa, von Seebach, of the Upper Oolites. The species is marked in my collection 
as Neritina “ subtransversa.” 
