50 MOLLUSCA FROM THE GREAT OOLITE. 



Localities. It occurs abundantly in the Minchinhampton district, but is chiefly 

 found in the planking of Minchinhampton Common ; it occurs likewise more rarely in the 

 Inferior Oolite of the same district. Ponton, Lincolnshire. 



Height of the largest example, 2^ inches ; length of the hinge line, 5 inches. 



Sub-Genus — Cucull^a, Lam., 1801. 



Gen. Char. Shell inequilateral ventricose; umbones large, distant, separated by a 

 ligamental area. The posterior surface with an oblique angle more or less prominent ; the 

 margins of the valves close all round. Hinge linear straight, teeth radiating obUquely 

 from beneath the umbones. Muscular impressions two, of which the anterior one is 

 supported by an elevated plate or ledge, projecting from the side of the shell ; the 

 posterior impression is rounded and faintly marked. 



CuCULLiEA CONCINNA, Phil. Tab. V, fig. 7. 



CucuLLiEA CONCINNA, Goldfuss. Petref., t. 123, f. 6? 1840. 

 _ _ Phil. Geol. York., i, t. 5, f. 9, 1835. 



? CucuLL/EA suBLiEViGATA, Zieten. Wurtt., p. 75, t. 56, f. 3, 1834. 



Testa ovato-rhomboided, convexd, umbonibus anteniedianis magnis depressis approxi- 

 matis ; latere antico brevi margine rotundo ; latere postico acute-carinato obliquo declivi ; 

 siiperficie striis concentricis regularibus crebris ; lateribus costis radiantibus paucis et 

 promAnentibus. 



Shell ovately rhomboidal, convex, umbones anterior to the middle of the valves, large, 

 depressed, and nearly touching each other ; anterior side short, its margin rounded ; 

 posterior side with an acute carina sloping obliquely ; the surface has closely arranged, 

 regular and very fine concentric striations ; the sides of the shell have a few radiating 

 })rominent costse, those upon the anterior side are four, elevated and distant. 



Our specimens agree with the figure of Phillips, but differ somewhat from that of 

 Goldfuss, which has fine radiating lines ; it is probable, therefore, that the latter is a 

 distinct species. 



It occurs not uncommonly in the shelly beds of the Great Oolite. 



Localities. Minchinhampton and Bisley Commons. 



CucuLL/EA GoLDPUSsi, Roemcr. Tab. V, fig. 4, 4a. 



CucuLL^.A GoLDFUSSii, Roemer, 1836. Nordd. OoL, p. 104, t. 6, f. 18. 



Testa trapeziformi convexd, concentrice subrugosd, antice rotundatd, angustatd, posterius 

 angulo rotu7ido cordato-compressd margine postico oblique truncato ; umbonibus crassis 

 prominulis incurvis, ared lanceolafd 5 — 6 striatd. {Roemer). 



