CAPULUS. 459 
Shell conical-depressed; base oval, but slightly expanding anteriorly; apex 
posterior with a slender spiral curve. The strong radiating ribs are closely 
arranged and decussated by encircling growth-lines, which are crowded on the 
posterior side, wide apart anteriorly. The actual apex is smooth, and presents an 
extremely small spiral knot, but the radiating ribs commence at a very early stage 
(figs. 2 a, 2b). 
Relations and Distribution.—Whether Capulus or Patella, this is by far the 
most abundant limpet-like shellin the Jurassic rocks. P. Tessonii may be regarded 
as a megalomorph from the “‘ Odlithe ferrugineuse ”’ of Moutiers, where the radial 
coste are wide apart. 
Capulus rugosus is certainly rare in the Inferior Oolite of this country. 
It is quoted from the “roestone”’ of Leckhampton Hill. Iremember also to have 
seen a specimen of considerable size from an inland locality of the Yorkshire 
Dogger. Though by no means abundant, it 1s better represented in the Lincoln- 
shire Limestone than in any other beds of Inferior Oolite age, e.g. Stoke Lodge, 
Ponton,and Weldon. Varieties of this species may also be noted in beds of later 
age than the Great Oolite. 
403. CAPULUS ANCYLOIDES, Sowerby, 1824. Plate XLII, figs. 3a, 3d. 
1824. ParEnLa ancyLorpus, Sowerby. Min. Conch., pl. edlxxxivy, fig. 2. 
1851. —  RuGosa, Sowerby, pars. Morris and Lycett, Gt. Ool. Moll., pt. 1, 
p- 89, pl. xii, figs. 1f, 14. 
Bibliography, Sc.—Originally described from Ancliff. Sowerby noted the 
decidedly spiral apex, “‘ which being turned to one side makes it resemble the 
Ancylus fluviatilis.” Morris and Lycett regarded it as the immature form of 
** Patella’’ rugosa. ‘There is only one specimen in the Sowerby type collection at 
the British Museum, somewhat cracked, but otherwise in good condition. 
Description : 
Length : : : . 675 mm. 
Width : A ; : . 39mm. 
Height ; ; j : . 2mm. 
Shell conical-depressed, smooth; base oval, apex spiral and posterior. The 
spiral coil is relatively large, and is marked by fine striz (not sufficiently shown 
in fig. 30); the rest of the shell is devoid of all ornament, except concentric lines 
of growth, which become strong towards the margin. 
Relations and Distribution—The apical conditions of Capulus (Patella) 
ancyloides are so different from those of Capulus rugosus, that this alone would 
