122 BUI.I.ETIN 31 133 



Phacoides {Miltha) claibornensis Dall, Trans. Wag. Ill, 1903, p. 

 1374, pl. 50, fig- 18. 



Conrad' s original description .—^vi}aor\)\Q.v\2x compressed, inequilat- 

 eral ; beaks small and acute ; disk with concentric, prominent, numerous 

 lamelliform striae ; ligament margin straight, oblique ; posterior end trun- 

 cated, or slightly emarginate ; ventral margin profoundly rounded. 



Height lyi inch. Length i^^inch. 



Locality. — Claiborne, Alabama. 



This shell occurs in the group at the base of Claiborne Bluff, belong- 

 ing to an older division of the Eocene than the Claiborne group above. 

 The cardinal teeth are prominent, and the pits profound. 



Dall is mistaken in his explanation of pl. 50, fig. 18, where 

 he refers this species to the "Claiborne Sands". It is strictly a 

 St. Maurice form. The specimens herewith figured, from Ivis- 

 bon, have less widely separated raised concentric ridges and the 

 cardinal margin is more curved than the specimens from the type 

 locality at the base of Claiborne Bluff. Conrad's type as well as 

 our specimens from that locality show clearly these differences. 



7)//^.— Phila. Acad. Nat. Sci. 



Horizon. — St. Maurice Eocene. 



Specimens figured. — Paleont. Coll. Cornell Univ. 



Localities. — Base of Claiborne Bluff, Ozark, lyisbon and 

 Hamilton Bluff, Ala. ; Ft. Gaines, Ga. ; just below City Point, 

 James River, Va. 



Lucfna rotunda Lea, Pl. 40. Figs, i, 2. 



L. symmetrica Con., Foss. Sh. Tert. Form., 1833, p. 40. 



Cyclas sym,m,etrica Con,, Amer. Jour. Conch., vol. i, 1865, p. 9. 



L. rotunda Lea, Cont. to Geol., 1833, p. 56, pl. i, fig. 28. 



L. rotunda de Greg., Mon. Faun. Boc. Ala,, 1890, p. 205, pl, 29, 



fig. 6-8, 

 L. symmetrica f Harris. These Bulletins, vol. 2, p. 263, pl. 14, fig. 4 



Lea's original description. — Shell orbicular, compressed, equilateral 

 concentrically and finely striate, flatfish over the umbones, folded before ; 

 substance of the shell thick, lunule small, lanceolate ; beaks very small, 

 pointed, recurved ; cardinal teeth indistinct ; cicatrices impressed, the an- 

 terior one rather long ; lines of growth numerous near the margin ; cavity 

 of the shell very shallow, having rather a large furrow across its centre ; 

 margin entire. 



