BIVALVIA. 173 



and somewhat distant imbrications, with oftentimes elongated and sometimes tubular 

 spinous processes ; outer surface covered with radiations, inner margins smooth ; mark of 

 attachment variable. 



Diameter, \\ inch. 



Localities. Bracklesham Bay {tJdwards). 



France : Barnes, Chaumont, Grignon, Calc. gross, moyen et sup. 



{Deshayes). 

 Sinde {Deshayes). 



The name of punctata was proposed for this species by M. D'Orbigny as one of prior 

 date, but the shell to which this name was given by Bruguiere is a species now living in 

 the sea near Guadaloupe, as stated by M. Deshayes, and is quite distinct, in which opinion 

 I coincide. Lamarck, therefore, appears to have been the first to describe the present 

 fossil, and the above name has been generally employed. The inside lining of the shell 

 is deeply and regularly punctulated, looking like the encrustation of Polyzoa, but this is 

 not visible on the impressions of the adductor muscles. This is strongly marked ; and the 

 two valves are very differently ornamented. The principal characters are the long spinous 

 fringes and the large radiating ridges between the laminae upon the right or upper valve ; 

 between the distant laminae of the lower valve the shell is ornamented with granules 

 arranged in a somewhat zigzag manner, very visible in perfect specimens from Grignon, 

 but indistinct upon the only individual of this lower valve that I have seen from our own 

 beds. The shell is attached by the left valve, and the mark of adherence is generally 

 small, as shown by the French specimens. 



This is a rare shell in our English beds. 



2. Chama fimbriata (?) Defrance. PI. XXV, fig. 8. 



Chama fimbriata, Defrance. Diet, des Sci. Nat., vol. vi, Suppl, p. 65, No. 3, 1818. 



— — Desk. An. sans Vert, dn Bass, de Par., vol. i, p. 584, pi. Iviii, 



figs. 23—25, 1860. 



— PONDEROSA, Id. Coq. Foss. des Env. de Par., vol. i, p. 248, pl. xx.xvii, 



figs. 9, 10, 1825. 



Spec. Char. Ch. " Testa orhiculatd, incrassatd, irregulari, convexd, multilamellatd, 

 intus l(Bvigatd; laniellis valvce inferioris brevibus, simpUcibus ; vah<s superioris longioribus, 

 laceris, plicatis ; dente cardinale magno valde sulcato." — Deshayes. 



Shell orbicular, thick, irregular, convex, and covered with numerous and close-set 

 lamellae ; inside smooth ; reflected ridges close and numerous. 



Diameter, 2 inches. 



Localities. Bramshaw {Edwards). 



France : Auvers, Valmondois, &c., Sables moyens {Deshayes). 



