210 CRETACEOUS LAMELLIBRANCITIA. 



Type.— From Norwich; in tiie Jiritish Museum. 



Distrihution. — Upper C-lialk (zone of Iklemnitdla mucronalu) of Norwich. 



GvKoi'i.KTUA, sp. Plate XXXIV, fig. 1 a — d. 



Ih'xcri plioii. — Iiiti'ht valve inflated, attnehcd \)\ a lar^'e poi'tioii of the dorsal 

 surface. Left valve convex, subcjuadrate, with a ])ointed tind incni'ved und)o. 

 Rinht valve ornamented with numerous, small radial ril)s which bear transverse 

 nodes or scales. Left valve with relatively few, stout ribs bearing strong, some- 

 what irregular, transver.so scales or lappet-like projections. 



AJfinifM's. — The ornamentation on the right valve is finer and that on the left 

 valve coarser than in G.cenomannisis (d'Orljigny ') ; also the t ransverse ornamenta- 

 tion of the ribs is much coarser and less regular.- 



Bemarkti. — The portion of the right valve which was attached includes the 

 umbo and the neighbouring parts, whereas in most examples of Oyroplenra only 

 the part in front of the umbo is attached. The size of the area which was attached 

 is larger than usual, but in other s]iocies it is seen that that area varies consideral)ly 

 in size in different examples.^ 



The only specimen seen was collected liy Mr. Francis R. B. Williams. 



Disti-il)iifin]i. — LTpper Chalk (zone of Actinocamax quadra Iiik) near the groyne 

 at Seaford. 



F«.miZ?/— CORBULID^, Fleming. 



Genus — CoRUULA, /. G. Ihnguiire, 1707. 

 (' Encyc. Mt'tb.,' Tabl. Vers., pi. 230.) 



Cnnnt'LA ANOur.ATA (rhillip^), 1820. Blate XXXIV, figs. 2—5. 



1829. IsocARDiA ANGULATA, J. Phillipn. Gcol. Yorks., p. 94, pi. ii, fiiis. 20, 21 



(ed. 3, 1875, p. 252). 

 1841. — _ p. ^. Burner. Die Versteiu. d. uord - deutsch. 



Kreidegeb., p. 70. 

 1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 204. 



1 ' Pal. Fraiu;, Terr. Cn't.,' vol. iv (1850), p. 261, pi. dxcv, fiii;s. 1—4. 



2 Douvilk', 'Bull. Soc. grol. do France,' ser. 3, vol. xv (1887). p. 771, pi. xxviii, fit;. 7. 



■'' In a specimen figured by Griepeukerl tbe surface of attacbmeut is unusually large ; ' Senon v. 

 Kimigsluttor ' ('Palseont. Abliaudl.,' v, 1889), pi. vii, fig. 3. 



