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825 



TERTIARY FAUNA OF FLORIDA 



Recent from the Carolinas to the West Indies, and on the west coast of 

 America at Mazatlan. 



Variety rotunda Dall. 



Ohgocene of the Chipola marls, Chipola River, Florida, Burns; of the 

 silex beds at Ballast Point, Tampa Bay, Florida, Dall ; of the Bowden marl, 

 at Bowden, Jamaica, Henderson. 



Shell resembling the ovata of the same size, but not attaining so large a 

 size as the adult ovata, with a more rounded posterior end and rather shorter 

 gape, the myophore decidedly larger, wider, and more conspicuous. Lon. 7, 

 lat. 3.5, diam. 2.8 mm. 



The differences between the recent and the Oligocene shells are so slight, 

 and the range of variation in the living specimens so marked, that I feel 

 unwilling, though the distinctive characters above mentioned seem constant, 

 to give the fossil shells more than varietal rank until I have seen a larger 

 number of specimens. 



Gastrocheena ligula H. C. Lea. 

 Gasfrochana ligula H. C. Lea, Trans. Am. Phil. Soc., 2d Ser., i.x., p. 234, pL 34, fig. 6, 

 1845; Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 571, 1863. 



Oligocene of the Oak Grove sand at Oak Grove, Santa Rosa County, 

 Florida, Burns; Miocene of the Natural Well, Duplin County, North Caro- 

 lina, Burns; and of Virginia, at Petersburg, Lea. 



This shell is distinguishable from the others by its narrow and slender 

 form and feeble concentric striation. 



G-astrochaena cuneiformis Spengler. 

 GasirocJiccna cuneiformis SpgL, Nova Acta Soc. Hafn., ii., p. 179, figs. 8-1 1, 1788 ; Lam., 



An. s. Vert., v., p. 447, 1818; Sby., Gen., figs. 3-5, 1820; Orbigny, MoH. Cubana, 



ii., p. 228, 1845. 

 Pholas Jiiajis Q\^eX\\-\, Syst. Nat., vi., p. 3217, 1792. 

 Chcena cuneiformis Retzius, Diss. Nov. Test., p. 19, 1788. 

 Fistula7ia rupestris Bosc, Hist. Nat. Cocp, ii., p. 205, 1802. 

 Rocellaria Mans H. and A. Ads., Gen. Rec. Moll., ii., p. 336, 1856 ; Tryon, Mon. Pholad., 



p. 47, 1862. 



Pliocene marl of the Croatan beds, North Carolina, Johnson ; of the 

 Caloosahatchie and Shell Creek-, Florida, Dall and Willcox; of Trinidad, 

 Guppy ; Pleistocene of South Carolina, Florida, and the West Indies ; recent 

 from Cape Fear, North Carolina, southward to the West Indies. 



