TRANSACTIONS OF WAGNER 

 I^IO 



TERTIARY FAUNA OF FLORIDA 



of mutations as V . inercenaria, though the normal form appears to be rather 

 regularly oval and only moderately convex. A variety which may be called 

 inftata is more trigonal and measures 60 mm. long, 55 mm. high, and 36 mm. 

 in diameter. It is from Bellefield, York River, Virginia. Another form which 

 I found mixed with the type at the same locality, and at first thought might be 

 distinct, is rounded, subtruncate behind, ver}- thick for its size, the surface 

 slightly undulate and with the lamellation obsolete. It may take the name of 

 variety nucea. It measures : length 33, height 29, and diameter 16 mm. The 

 measurements of a normal, oval specimen from Shiloh, New Jersey, are : 

 length 68, height 55, and diameter 24 mm. A more inflated, thin specimen 

 from Maryland measures : length 75, height 61, diameter 36 mm. 



Venus tridacnoides Lamarck. 

 Cyprina tridacnoides Lamarck, An. s. Vert., v., p. 558, 1818; after Lister, Conch., pi. 



ccccxcix., 1692. 

 Venus tridacnoides Deshayes, An. s. Vert., ed. ii., vi., p. 591, note, 1835 ; Conrad, Fos. 



Medial Tert, p. 10, pi. vii., fig. 2, 1838; Tuomey and Holmes, Plaice. Fos. S. Car., p. 



8s, pi. xxii., fig. I, 1857; Emmons, Gaol. Rap. N. Car., p. 292, 1858. 

 Venus deformis Say, Journ. Acad. Nat. Sci. Phila., iv., p. 148, pi. xii., fig. 2, 1824; Morton, 



Syn. Org. Rem., App., p. 2, 1834. 

 Venus difformis Emmons, Geol. Rep. N. Car., p. 292, 1858. 

 Mercenaria tridacnoides Conrad, Proc. Acad. Nat. Sci. Phila., xiv., p. 574, 1863 ; Meek, 



Checkl. Miocene Fos., p. 9, 1864. 

 Venus Rileyi Conrad, Fos. Medial Tart., p. 9, pi. vi., fig. i, 1838; Tuomay and Holmes, 



Pleioc. Fos. S. Car., p. 78, pi. xxi., fig. 8, 1857; Emmons, Geol. Rep. N. Car., p. 292, 



1858; Heilprin, Trans. Wagnar Inst., i., p. 102, 1886. 

 Mercenaria Rileyi Conrad, Proc. Acad. Nat. Sci. Phila., xiv., p. 574, 1863 ; Meek, Checkl. 



Miocene Fos., p. 9, 1864. 

 Mercenaria percrassa Conrad, Am. Journ. Conch., iii., p. 13, 1867; iv., p. 278, pi. xix., 



fig. I, 1868. 



Miocene of Maryland at Plum Point ; of Virginia at Petersburg ; City 

 Point and Grove Wharf on the James River; the York River at Yorktown, 

 Bellefield, Temple Place, and Gloucester Point ; Hanover and Suffolk ; of North 

 Carolina at the Duplin County Natural Well and Magnolia ; in Edgecombe 

 County and at Wilmington ; of South Carolina at and near Darlington ; of 

 Florida at Darling's Slide, Calhoun County ; the upper bed at Alum Bluff, at 

 Jackson Bluff, and sixteen miles southwest of Tallahassee ; Pliocene of the 

 Waccamaw River, South Carolina, and of the Caloosahatchie and Shell Creek, 

 Florida; Pleistocene of Heislerville, Cumberland County, New Jersey (?). 



