92 MOLLUSCA FROM THE GREAT OOLITE. 
P. Testa conicd, depressd; ambitu ovali; apice acuto, antemediano ; costulis radi- 
antibus inequalibus irregularibus, flecuosis ; striis transversis tenuissimis, irregularibus. 
Shell conical, depressed ; base oval; apex acute, placed anterior to the middle of the 
shell; ribs radiating, unequal, irregular and waved; stria transverse, irregular, and 
very fine. 
The radiating ribs are sometimes only visible towards the margin; the lines of growth 
are few and uncertain ; as in the other Pafe//e, the degree of elevation varies considerably, 
the apex approaching more nearly to the anterior border in such as are depressed ; the 
colours are sometimes partially preserved. 
Locality. Vt is not uncommon, and occurs in all the shelly beds of the Great Oolite 
near Minchinhampton. Our largest specimen is 14 inches in its longer diameter. 
M. D’Archiac describes this species as occurring in the Great Oolite of Aubenton, 
France, where it is rare. 
PATELLA SUPRAJURENSIS, Buv. Plate XII, figs. 9, 9a. 
? PATELLA SUPRAJURENSIS, Buvignier. 1843. Mém. Soc. Philom. de Verdun (Meuse), 
pl. 5, fig. 10. 
P. Testé ovato-depressd ; apice subcentrali; ambitu oval; striis incrementi irregu- 
laribus, distinctis ; striis concentricis tenuissimis crebris. 
Shell ovate, depressed ; apex subcentral; base oval; lines of growth irregular, strongly 
marked; concentric striz closely arranged and very fine. 
The absence of radiating coste sufficiently separates this from P. Awbentonensis, the 
general figure of which it nearly resembles; the lines of growth are hkewise much more 
strongly marked. 
Locality. It is comparatively rare, and is not confined to any of the shelly beds of the 
Oolite at Minchinhampton. Found also in the Portland limestone of Varennes. (Bwv). 
PATELLA ARACHNOIDEA. Plate XII, figs. 8, 8a, 0. 
P. Testa parva, ellipticd et conicd; apice acuto centrali; costulis longitudinalibus minutis 
et distantibus; lineis transversis numerosis, elatis et trregularibus. 
Shell small, elliptical and conical; apex acute, central; with longitudinal, minute, and 
distant ribs ; transverse lines very numerous, elevated, and irregular. 
This small species has an elevated, acute apex, and displays under the magnifier a 
beautiful net-work kind of surface ; the encircling lines are three or four times more dense 
than the longitudinal elevations. The form is nearly that of Pi/eolus plicatus, but more 
acute, and the character of the surface is altogether different. 
Locality. The shelly beds at Quarhouse, which correspond to the planking of Min- 
chinhampton Common, have furnished our specimens. 
