1919.] NATURAL SCIENCES OF PHILADELPHIA. 47 



Type Locality. — Walker's Bluff, Bladen County, North Carolina. 

 Waccamaw Formation. 



Observations. — Pandora tuomeyi has apparently been confused 

 with the recent Pandora trilineata Say, a rather smaller, and rela- 

 tively lower species, more tapering in outline posteriorly. The 

 most fundamental difference lies, however, in the dentition. In 

 general, the cardinals of the recent species are the more compressed, 

 the more produced, and the more sharply cut. In particular, 

 the inner surface of the right valve of the Tertiary form, in front 

 of the middle cardinal, is not thickened, but often feebly chan- 

 nelled; the middle cardinal is hatchet-shaped or rhomboidal and 

 shorter than the elevated laminar tooth of P. trilineata; the pos- 

 terior cardinal is shorter, heavier, and less uniform in elevation, 

 and the inequality between the two right cardinals is much more 

 marked in the fossil than in the recent species. In the left valve, 

 the resilial pit in tuomeyi is broader and less produced, and the 

 cardinal upon its anterior margin, shorter and less sharp; the left 

 cardinal in P. trilineata has strongly defined margins, bears a 

 flange upon the dorsal half of its inner surface, and terminates 

 ventrally near the dorsal end of the anterior adductor impression; 

 the anterior cardinal of tuomeyi, on the other hand, suggests much 

 more strongly a kinship to the sub-genus Kennerleyia; its anterior 

 limit is often ill-defined, and the hiatus between such a tooth and 

 the incurved and calloused surface of the anterior margins of 

 Kennerleyia is not great; the cardinal in tuomeyi, furthermore, is 

 not expanded dorsally into a flange, and is placed forward so that 

 its ventral termination is at the medial line of the adductor im- 

 pression. 



The young of Pandora carassidens Conrad, while similar in 

 dentition, are relatively higher, less alate, heavier, and less com- 

 pact in shell texture, and show a very much stronger tendency 

 toward radial sculpture in the right valve. 



Distribution. — Duplin Formation. Darlington, Darlington 

 County; Muldrow's Mills, 5 miles southeast of Mayesville, Sum- 

 ter County, South Carolina. Waccamaw Formation. Walker's 

 Bluff, Cape Fear River, Bladen County, North Carolina. 



Collections. — U. S. National Museum. Johns Hopkins Uni- 

 versity. Academy of Natural Sciences of Philadelphia. 



Strigilla eutykta new species. Plate III. figs. 4, 8. 10. 



General Characters. — Shell sub-orbicular, slightly oblique, in- 

 equilateral, moderately inflated in the umbonal region. Anterior 



