TRANSACTIONS OF WAGNER 



TERTIARY FAUNA OF FLORIDA 



lines, slightly varying in strength ; beaks low, inconspicuous ; ligament short, 

 teeth short and small, hinge-line narrow, briefly excavated in front ; muscular 

 and pallial impressions normal. Alt. 8, lat. 10.5, diam. 5 mm. 



This species differs from the preceding by its very thin shell, less turgid 

 and globose ; the shorter and most rounded specimens are considerably less 

 inflated than in the nucleiformis, which does not seem to attain so large a size. 



Diplodonta acclinis Conrad. 



Plate 28, Figures 2, 13. 



Lucina acclinis Conrad, Fos. Tert. Form., p. 21, pi. 6, fig. 2, 1832; Whitfield, Mio. Moll. 



N. J., p. 62, pi. X., figs. 5, 6, 1895. 

 Mysia americana Conrad, Fos. Medial Tert., p. 30, pi. 16. f. 2, 1838 (not Lucina ameri- 

 cana Defrance, 1823) ; Proc. Nat. Inst., ii., p. 185, 1842; Meek, Mioc. Checkl., p. 8, 

 1864. 

 Diplodonta acclinis Conrad, Proc. Acad. Nat. Sci. Phila., ix., p. 166, 1858; Dall, Trans. 

 Wagner Inst., iii., p. 923, 1898. 



Basal Miocene of Shiloh, Cumberland County, New Jersey ; Miocene of 

 Jones Wharf, Maryland, Greensboro', Maryland, York River, Virginia, Wil- 

 mington and various localities in Duplin County, North Carolina ; Pliocene of 

 Tilly's Lake, Waccamaw River, South Carolina, of Walton County, Florida, 

 and of the Caloosahatchie River : Burns, Harris, Stanton, and Dall. 



This is the finest and most conspicLious species of the Miocene ; if it 

 possessed, when living, a strong, polished epidermis it would probably have 

 foimd a place in the section Felaniella,- to which its form and minor characters 

 show some resemblance. 



Diplodonta ( Sphserella ) subvexa (Conrad). 

 Sphccrella subvexa Conrad, Fos. Medial Tert., p. 18, pi. 10, fig. 2, 1838; Proc. Acad. Nat. 



Sci. Phila. for 1863, p. 577. 

 Erycina subconvcxa Orbigny, Prodr.. iii., p. 115, 1852. 



Miocene of the James River near Smithfield, Virginia, Conrad ; and of the 

 Nansemond River near Suffolk, Virginia, Burns. 



This fine species has been discussed in connection with the section Sphce- 

 rclla. It appears to be rare. Our largest specimen measures, alt. 36, lat. 40, 

 diam. 30 mm. 



The Sphccrella orcgona Conr., of the " Smithsonian Checklist of Eocene 

 Fossils of North America" (p. 6, 1866) appears to be a nude name, at least 

 I have not been able to find any diagnosis of it in the literature, and it has not 

 been figured. 



