144 EOCENE MOLLUSCA. 



4. Cardita carinata, /. Souoerhy. Tab. XXII, fig. 15, u, b. 



Venzbicaedia carinata, J. Sow. Min. Conch., t. 259, fig. 2, 1820. 



Sjjec. Char. C Testa elongato4ransversd vel ovato-ohlongd, compressiusculd, tenui, 

 valde incequilaterali, radiatim costatd, costis 20 — 22, angidatis, carinatis, et nodulosis ; 

 margine ventrali co7ivexiuscidis ; umhonibus minimis, ohliquis, depressis; lunula minutis- 

 simd, profunda, Icevigatd ; car dine angusto, dentibus elongatis. 



Shell elongately transverse or ovately oblong, slightly compressed, thin, very inequi- 

 lateral ; radiatingly costated with 20 to 22 angular, carinated, and nodulous ribs ; ventral 

 margin slightly curved ; beaks small, depressed, lunule deep and smooth ; hinge narrow, 

 teeth elongated. 



Length, \\ inch; height, |^ths of an inch. 



Locality. Bracldeshara Bay. 



This is an elegant species, and by no means rare at the above locality, to which it 

 appears to be restricted. The shells are thinner and more fragile than those of the 

 generality of species in this genus. The ribs upon this species are triangular and 

 obsoletely tricarinate, that is to say, there are two faint rays, one on each side of the 

 regular keel, which is in perfect specimens ornamented with nodules ; the bases of the 

 ribs meet, and there is no flat part in the interspaces. The siphonal region is rather 

 compressed, or not so tumid as the pedal side. The interior is thickened in aged speci- 

 mens, and the muscle-marks then deeply impressed. 



5. Cardita crebrisulcata, Edwards, MS. Tab. XXII, figs. 4 and 8. 



Spec. Char. C. Testa suborbiculari, incequilaterali, turgidd, crassd, subspharicd, 

 radiatim costatd, costis 20 — 24, angustis, squamosis, squamulis imbricatis ; umbonibus 

 parum obliquis, cordatis ; lunula Icevigatd, concaviusculd ; cardine angusto, dente unico 

 in valvd dextrd elongato ; dentibus diiobus in altera valvd. 



Shell suborbicular, inequilateral, tumid, thick, nearly spherical ; costated ribs 20 — 24, 

 narrow, and ornamented with numerous fine imbrications ; umbones slightly oblique, 

 heart-shaped; lunule short, smooth, slightly depressed; hinge narrow; one elongated 

 tooth in right valve, with a narrow depression in the left. 



Diameter, fths of an inch. 



Localities. Bramshaw and Huntingbridge [Edwards). 



This much resembles sulcata, but it has a larger number of ribs, and these are more 

 prominent, nodulous and imbricated ; the interspaces are narrow and deep. 



There are also some other specimens, to which is attached the name of subprofunda 



