42 SUPPLEMENT TO GREAT OOLITE MOLLUSCA. 
Geological Position and Localities. It occurs rarely in the Cornbrash of Scarborough. 
Dr. Oppel records it in the same geological position at Marquise, near Boulogne ; also at 
Egg, near Aarau, Switzerland. Goldfuss records it at the latter locality, and at Basel. 
Lima RicipuLa, Phil, sp. Tab. X XXIII, figs. 7, 7 a. 
PLAGIOSTOMA RIGIDULUM, Phil. Geol. York., i. t. 7, fig. 13. 
Testa elongata, convexa, per-obliqua, umbonibus obliquis, acutis, auriculis parvis sub- 
@qualibus ; latere antico elevato, eaxcavato, postico elliptico curvato ; valvis costulis radi- 
antibus angustis, rotundatis, regularibus, sed undulatis et granulatis; interstiis duplo 
latioribus subtillissime transversé striatis, striisque regularibus instructis. 
Shell elongated, convex, very oblique; umbones small, pointed anterior; auricles 
small, nearly equal; anterior side very convex, with a steep, excavated border ; posterior 
side curved elliptically; the entire surface has delicate but rounded, elevated, and finely 
knotted radiating costa, gently waved and separated by interstitial spaces twice the 
breadth of the coste ; the spaces have very fine, regular, and closely arranged transverse 
striations ; the plications of growth are few, but become prominent near to the lower 
border. 
One of the most elongated and oblique of the Jurassic Lime. The general figure and 
ornamentation would much resemble Lima ovalis, Sow., if the convexity of the anterior 
side were not much greater, and the coste more elevated, in the Cornbrash shell; the 
striations are so densely arranged that the spaces do not present a punctated aspect, as is 
usually seen when the striations are more distant, and larger. 
Dimensions. Length, 20 lines; breadth, 12 lines; diameter through both the valves, 
10 lines. 
Geological Position and Locality. The Cornbrash of Scarborough, in which it is 
abundant. 
Moproxa crpposa, Sow. Tab. XXXIII, figs. 11, 11 a. 
Moproua GrBBosa, Sow. Min. Con., t. 211, fig. 2. 
— -RENIFoORMIs, Sow. Ib. fig. 3. ? 
— — D Orb. Prodr., i, p. 282. 
—  GipBosa, Mor. Catal., 1854, p. 210. 
Testa elongato-ovato, convexa subreniformi umbonibus curvatis acutis sulco obliquo 
antico ; latere antico inferne sinuato, latere postico elliptico curvato ; lateribus plicis magnis 
concentricis distantibus. 
Shell ovately elongated, very convex ; umbones pointed, curved forwards ; an oblique 
sulcation proceeds downwards and forwards to the lower part of the anterior border, which 
