PHOLADOMYA. 245 



nimiorous, fine, regular ribs parallel with the posterior margin ; on the remainder 

 of the shell similar ribs, but running in a radial direction, occui-. 

 Measurements : 



(1) (2) (3) (4) 



Length . . 37 . 88 . 30 . 20 mm. 

 Height . . 23 . 22 . 21 . 1-t ., 

 Thickness . 15 . 14 . — . 10 „ 



(1) Chalk Marl, Chard. 

 (2, 4) Chloritic Marl, Devizes. 

 (3) Chalk Marl, Ventiior. 



Abilities.— In this species the shell is more elongate and less convex, the carina 

 more prominent, and the postero-dorsal area larger than in T. mf inula fa (p. 241). 

 T. carinifera is closely allied to T. I'lcgmis (d'Orbigny),' froni the Cenomanian of 

 St. Sauveur, l)ut is less elongate. T. German (Greinitz)- from the Senonian, is 

 regarded by Bi-auns'^ as a synonym of T. carinifera ; but without seeing specimens 

 of the former it is ditlicult to express an opinion of its relationship. 



licmarls. — The specimens vary considerably in the pro])ortion of leiigtli to 

 height, but in some cases the differences are probably due partly to crushing. 

 The shell itself is seldom preserved. 



Type. — The type came from the Cenomanian of Dowlands (South Devon) and 

 was originally in the collection of Sir H. T. De la Beclie, but cannot now l)e 

 found. 



Distribution. — Chloi'itic Marl of Devizes and Maiden Bradley. Chalk .Marl of 

 Veutnor, Evershot, and Chard. 



i^am%— PHOLADOM YJ D^¥., (Iraij. 



Genus — Puoi-.viH>MY.\, (/. B. Soice,ii/, 1825. 

 (' Genera Eee. ami Foss. Shells,' uo. xix, pi. .x.xxvii.) 



Phol.\.domv.v Cok.nuki.iax.v {(VOrliiij)iii), 1844. Plate XLT, figs. 2'/,//, '■\. 



1844. Cabdium CouNUELiANUJi, A. d'Oihi(jiiij. I'al. Frauc. IVrr. Crt't., vol. iii, 



p. 23, pi. cclvi, figs. 1, 2. 



1845. — — E. Forbex. Quart. Jourii. Greol. Soc, vol. i, p. 243. 

 1850. Pholadomya Cornueliana, A. crOrhiijiiy. Prodr. ile Pal., vol. ii, p. 117. 

 1854. Cardium Cornuelianum, /. Morris. Cat. Brit. Foss , ed. 2, p. 192. 



1 'Pal. Fran9. Terr. Crct.,' vol. iii (1845), p. 386, pi. ccclxxiii, figs. 3 — 5. 

 - ' Quaiiersandst. oder Kreidegeb. in Deutschlaud ' (1850), p. 150, pi. x, figs. 9 — 11. 

 * ' Seuon. Mergel d. Salzberges,' Zeit.schr. f. d. gesammt. Naturwiss., vol. xlvi (1876). p. 35!'. pi. x, 

 figs. 18, 19. 



