BIVALVIA. 175 



4. Chama squamosa, Solander. PI. XXV, fig. 6 a — d. 



Chama sauAMOSA, Solander (in Brander). Foss. Hanton., pi. vii, figs. 86, 87, 1776. 

 _ — /. Sowerby. Min. Conch., t. 348, 1822. 



— — G.B. Sowerby. Genera of Shells (CAawja), fig. 4, 1839. 



Spec. Char. Testa crassd, suborbiculatd, irregulari, midtilamellatd, Jimbriatd, longi- 

 tudinaliter muUistriatd aid radiatd ; lamellis numerosis, incrassatis, subpUcatis ; striis 

 Jlexuosis ; wnbone valvcB inferior e major e, contorto, aliquando producto ; car dine crasso, 

 rugoso. 



Shell thick, suborbicular, irregular, covered with numerous fimbriated laraellge, and 

 numerous longitudinal or rather radiating and bending or undulating striae ; lower or left 

 valve the larger, with the umbo sometimes much produced ; hinge with a large rugose 

 tooth ; inner margin of valve smooth. 



Longed diameter, Ifths inch. 



Locality. Barton. 



This is very abundant at Barton, but I do not know it from any other locality, although 

 it is given in Morris's ' Catal. of Brit. Foss.,' 2nd Edit., p. 194, as from Bracklesham Bay. 

 In the ' Ann. du Mus.,' vol. viii, p. 348, Lamarck refers his Paris Basin shell C. lamellosa 

 to the British species figured by Solander. Deshayes omits Solander's name from his 

 synonyms, giving his reasons for believing the French shell to be quite distinct ; and I am 

 of his opinion. Our shell is very variable, but it is always closely radiated and fimbriated. 

 Sometimes specimens are much distorted, resembling in that respect Biceras ; adhering 

 only by the umbo, the shell twisting in a spiral manner, carrying up a depressed ridge of 

 the deserted and disused connector (fig. 6 d^. Some specimens are tinted with a reddish 

 brown, which I imagine to be part of the original colour. 



5. Chama SULCATA (?), Deshayes. PI. XXV, fig. 7. 



Chama sulcata, DesA. Coq. Foss. des Env. dePar., vol. i, p. 250, pi. xxxviii,.figs. 8, 9, 1825. 

 — — Id. An. sans Vert, du Bass, de Par., vol. i, p. 585, 1860. 



Spec. Char. C. '' T. ovato-orbiculatd, convexd, turgidd, profunda, lamellosa, longitu- 

 dinaliter multisulcatd ; lamellis irregularibus, brevissimis ; sulcis undulatis, numerosis, con- 

 vexis ; dente cardinali oblongo, brevi, sidcato." — Desh. 



Shell irregular, ovate or orbicular, convex, thick, tumid, deep, and lamellated ; longi- 

 tudinally sulcated or radiated; concentrical or periodical lamellae irregular and short; 

 cardinal tooth short and sulcated. 



Localities. Bracklesham Bay and Barton {Edwards). 



France : Chaumont, Calc. gross, inf. {Deshayes). 



