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TERTIARY FAUNA OF FLORIDA ^^ 



Cardium (Cerastoderma) robustum Solander. 

 Cardium robustum Solander, Portland Catalogue, p. 58, 1786, after Lister, Hist. Conch , 



pi. 328, fig. i6s, 1770. 

 Cardium ventricosum Bruguiere, Enc. Meth., i., p. 228, 1789; plates vol. i., pi. 299, fig. i, 



1792 ; Wood, Gen. Conch., p. 220, 1815. 

 Cardium magnum Born, Ind. Mus. Vind., p. 34 ; Test. Mus. Vind., p. 46, pi. 3, fig. 5, 



1780; not of Linne, Syst. Nat., ed. x., p. 680, 1758. 

 Cardium magnum Reeve, Conch. Icon., ii., Cardium, pi. iv., fig. 20, 1844; and of the 



majority of American authors, but not of Linne. 

 Cardium maculatum Gmelin, Syst. Nat., vi., p. 3255, No. 38, 1792 ; Dillwyn, Cat. Rec. 



Shells, i., p. 121, 1817; Ravenel, Cat., p. 5, 1834; not of Reeve, 1844. 

 Cardium robustum Solander, Dillwyn, op. cit., i., p. 121, 1817. 

 Cardium carolinensis (sic) Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 576, 1863 ; 



not of Conrad, in Kerr, Rep. Geol. N. Car., App., p. 15, 1875. 

 Cardium magnum Tuomey and Holmes, Pleioc. Fos. S. Car., p. 63, pi. 19, fig. i, 1856; 



Heilprin, Trans. Wagner Inst., i., p. 103, 1887. 



Upper Miocene of Wilmington, North Carolina, Stanton; Pliocene of 

 Darlington, South Carolina, of the Croatan beds of North Carolina, of the 

 Caloosahatchie and Shell Creek, Florida; Pleistocene of Simmons Bluff, 

 South Carolina, of the Brunswick Canal, Georgia (Couper), and of many 

 locaHties in the Floridian, Gulf, and Antillean region; recent from Cape May, 

 New Jersey, south to Cuba, Jamaica, and Campeche. 



As Solander gives a reference to Lister's perfectly recognizable figure 

 (the same upon which Gmelin's name of maculatum was afterwards founded), 

 there can be no doubt his name should be adopted. 



As regards the ribs, the fossil species vary in having from twenty to 

 twenty-eight, the majority in the list having between twenty and twenty-four. 

 The recent ones vary between twenty-two and thirty, the majority having 

 twenty-three to twenty-seven. These figures are exclusive of the flattened 

 rays on the posterior area, which are invariably seven or eight, there being 

 one more on one valve than on the other. The total rays or ribs would then 

 amount to from thirty to thirty-five in the great majority of specimens. There 

 is in the list as I have recorded it for my own study a slight apparent ten- 

 dency to a less number of ribs in the fossils than in the recent shells, and in 

 the northern compared with the southern specimens, as has been observed here- 

 tofore with ribbed pelecypods considered by me in this memoir. The number 

 of specimens of which the ribs were counted was forty-five. The Miocene 

 specimens examined had twenty-seven and twenty-three ribs, and those with 

 fewer ribs than this were only four in number, of which one was a recent shell 



