TRANSACTIONS OF WAGNER 

 994 



TERTIARY FAUNA OF FLORIDA 



only difference observable being that the recent shells would average slightly 

 heavier. The latter are very variable in color and sculpture. There does not 

 seem to be any Semele lata of Adams, and the name used by Miss Bush for 

 this species is apparently an error of labelling. 



Section Semelina Dall. 



Semele nuculoidea Conrad. 



Amphidesma nuculoides Conr., Am. Journ. Sci., vol. xli., p. 347, Oct., 1841 ; Fos. Medial 



Tert, p. 73, pi. 41, fig. 6, 1845. 

 Abra nuculoides Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 574, 1863; Meek, S. I. 



Checkl. Mio. Fos. N. Am., p. n, 1864. 

 Semele nuculoides Dall, Bull. 37, U. S. Nat. Mus., p. 62, 1889. 



Oligocene of Oak Grove, Santa Rosa County, Florida, Burns ; also in the 

 Miocene of North Carolina at Wilmington, and at Magnolia and the Natural 

 Well, Duplin County ; of Virginia in the Yorktown beds of the York River ; 

 Pliocene of the Caloosahatchie beds, Florida ; living from North Carolina, near 

 Cape Hatteras, southward to the West Indies and west to Pensacola, Florida. 



The variety striulata Dall, from the uppermost Oligocene of Oak Grove, 

 Florida, differs from the typical Miocene phase of this species by its finer and 

 closer striation, and in most of the specimens by its more parallel-sided and 

 elongated shell. The variety lirulata Dall, which is chiefly found among the 

 recent specimens, has faint radial striation distally. The recent shells are 

 usually whitish, but the color varies and may be yellow, red, or rayed with 

 red; the variations of the outline are proportionately about the same as in 

 the larger species of the genus. The remark that the lateral teeth of the 

 hinge are obsolete shows that Conrad had only a left valve to study, as in 

 the right valve they are strong. The pit for the reception of the resilium is 

 not conspicuous and in slightly worn specimens it is difficult to make out. The 

 concentric striation is somewhat sharper, and the interspaces are more ele- 

 vated over the posterior dorsal slope, as usual in the genus. The largest of the 

 Duplin County specimens measures 7 mm. long by 5 mm. high ; no recent 

 specimens have come to hand as large as this. 



Semele cythereoidea n. sp. 



PLATE 44, FIGURE 5. 



Upper Oligocene of the Chipola River, Calhoun County, Florida ; Dall. 

 This species, which is abundant in the Chipola marl, is much like the pre- 

 ceding, from which it differs by its shorter and more triangular form, like 



