90 MOLLUSCA FROM THE GREAT OOLITE. 



Leckhampton Hill, near Cheltenham {Buckman) ; and in the Great Oolite of Langrune, 

 Luc, Ranville, &c., Normandy (Deslongchamps). 



The Patella Tessonii (E. Desk), which is referred to this species with some doubt, was 

 obtained from the Inferior Oolite of Moutiers-en-Cinglais by M. Tesson. 



Patella paradoxa. Plate XII, figs. 2, 2a, b. 



P. Testa suborbiculatd, apice depresso, versus marginem anticum injlexo, latere antico 

 concavo, postico convexo ; costis radiantibus, elatis, rotundatis, undulatis, transversim striatis, 

 et distantibus, costis posticis 9 magnis, lateralibus obscuris, anticis congestis et corrugatis. 



Shell suborbicular, apex depressed, turned towards the anterior margin ; anterior side 

 concave, posterior convex ; ribs radiating, large, distant, elevated, rounded, undulated and 

 impressed by transverse striae ; the posterior costse, about 9 in number, are large, those 

 upon the sides of the shell are depressed and obscure ; the anterior ribs are congested and 

 corrugated. 



The general aspect of this singular shell reminds us of Patella rugosa, which it follows 

 somewhat in its varieties of aspect. When young, the few posterior costse are prominent, 

 but the sides of the shell are smooth, and the general figure is more depressed and 

 elongated ; the costae are much larger than in P. rugosa, more distant, and, in consequence, 

 much fewer ; and the entire shell has a wrinkled and very rugose aspect. The colours are 

 usually more or less preserved. 



Locality. This may be considered as the most rare of the Minchinhampton Patellae. 

 The few examples obtained have been found in the planking, or in the equivalent white 

 stone of Eastcombs and Bussage. The young form, were it known only by a single 

 specimen, would probably be regarded as a distinct species ; the older specimens attain 

 nearly the dimensions of a middle-sized P. rugosa. 



Patella sulcata, Deslongchamps. Plate XII, figs. 3, 3 a, b. 



Patrlla sulcata, Deslong champs. 1842. Mem. Soc. Linn, de Normandie, vol. vii, 



p. 115, t. 7, figs. 9—11. 

 Helcion — B'Orb. 1850. Prod. Paleont., p. 272. 



P. Testa subcllipticd, conico-depressd ; apice recto; costis elatioribus radiantibus, 

 inaqualibus, squamviato-rugosis, sidcis profundis interpositis, margine subcrenato. 



Shell subelliptical, conical, but depressed ; apex erect ; ribs elevated, radiating, 

 unequal, squamose or rugose, with deep interstitial spaces ; margin somewhat crenated. 



The costae do not increase in size materially as they approach the margin, and the 

 additional ribs which are added with increase of growth equal the others in size. This 



