296 GASTEROPODA OF THE INFERIOR OOLITE. 
three nearly equal, equidistant spiral girdles (in the penult usually a subordinate 
fourth), which are evenly and regularly serrated. The appearance is almost that 
of a coil of whipcord wound round a top. 
The body-whorl considerably exceeds half the height of the shell; it is 
rounded, but not ventricose. There are four principal spiral girdles similar to 
those already described, and in the base about six spirals similarly ornamented, 
and of nearly equal prominence, but becoming less salient towards the point of the 
columella. 
The aperture is subcircular, flattened anteriorly with a straight pillar lip and 
large callus, much thickened towards the centre, so as to form a kind of tooth ; 
outer lip crenulated. 
Relations and Distribution.—The regularity, prominence, and peculiar rope-like 
character of the spiral ornaments clearly distinguish this from any other species in 
the Inferior Oolite of England. Laube’s species is near to it, but appears more 
eucycloid in character. 
The figured specimens are both from Bradford Abbas, most probably from the 
concavus-zone. It occurs also on nearly the same horizon in the neighbourhood 
of Beaminster and at Stoford. There were three specimens without locality in 
Dr. Wright’s collection. There is also a specimen in a ragstone matrix said to 
come from Cleeve Hill. Altogether about a dozen specimens are known to me. 
Attention is here drawn to a shell (Pl. XXIII, fig. 14) which appears to be an 
Amberleya rather than a Littorina. The following are the dimensions :—Length 
20 mm., length of body-whorl to total height 55: 100, spiral angle 50°. The 
style of ornamentation is somewhat similar to that of Littorina polytimeta, but the 
serrations are rather finer, and there are four spirals in the whorls of the spire, 
and also the spirals in the base are more numerous. In conformity with the shape 
of the shell the aperture is more elongate, otherwise similar, and with a similar 
tooth-like thickening. 
This form is rare in the ‘‘ Base-bed” at Lincoln. 
930. Livrorina Partntresu, Morris and Lycett, 1851. Plate XXIII, fig. 16. 
1851. Turso Purniresu, Morr. and Lyc. Great Ool. Moll., p. 117, pl. xv, fig. 12. 
1884. Lrrrortna Puritrestt, Morr. and Lyc. Hudleston, Geol. Mag., dec. 3, 
vol. i, p. 242, pl. viii, fig. 1. 
Description : 
Length . . 12—18 mm. 
Length of body-whorl to total height » 601065 
Spiral angle : : . 68% 
