TRANSACTIONS OF WAGNER 

 1248 



TERTIARY FAUNA OF FLORIDA 



posterior area ; valves with the umbones not compressed, moderately convex ; 

 pallial line slightly flexuous behind, inner margins of the valves entire, the 

 cardinals not grooved ; the ligament and other characters as in Gafrarium s. s. 



?Section Radiocrista Dall, 1902. Type Venus pulcherrima Deshayes, 

 Journ. de Conchyl., viii., p. 381, pi. xiv., figs, i, 2, 1860. Tertiary. 



Shell with the form of Chionella, the disk and anterior part elegantly, regu- 

 larly concentrically sulcate; the dorsal posterior area equally divided between 

 the valves, nearly smooth, separated from the disk by strong radial ribbing; 

 the lunule not definitely circumscribed but indicated by a thickening of its 

 margins and concentrically striated. Interior and geological horizon unknown. 



This remarkable fossil is provisionally located here pending further informa- 

 tion. It is probably of European Tertiary origin. 



Section Gouldia C. B. Adams. 



Gafrarium (Gouldia) insulare Dall and Simpson. 

 Circe (Gouldia) insularis Dall and Simpson, Moll, of Porto Rico, p. 487, pi. lv., fig. 2, 



1001. 



Oligocene of the Bowden marl, Bowden, Jamaica ; living at San Juan and 

 Mayaguez harbors, in Porto Rico, in thirty fathoms sand. 



After a careful examination of both recent and fossil specimens I am un- 

 able to mention any characters which may be said to constantly differentiate 

 them. On the whole, the fossils are a little more inflated and usually more 

 produced in front, but these features are inconstant. 



Gafrarium (Gouldia) erosum n. sp. 

 PLATE 57, FIGURE 10. 



Oligocene of the Chipola River, Calhoun County, Florida ; Burns. 



Shell rounded trigonal, rather thin, subcompressed, the surface finely, evenly, 

 closely, concentrically sulcate, with a few almost microscopically minute radial 

 striulae sometimes visible under a lens in the sulci near the ends of the shell : 

 most of the specimens appear to be without radial sculpture ; beaks small, 

 pointed, slightly anteriorly directed over a lanceolate lunule bounded by an in- 

 cised line ; hinge normal ; pallial sinus barely indicated ; inner margins smooth, 

 the right posterior dorsal margin grooved to receive the bevelled edge of the 

 margin of the opposite valve. Length 8.3, height 7.2, diameter 4.0 mm. 



This species is especially characterized by its fine, even, concentric sculpture 

 and nearly total absence of radial striae. 



