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1255 



TERTIARY FAUNA OF FLORIDA 



Cytherea (Callista) gigantea Dall, Bull. U. S. Nat. Mus., No. 37, p. 56, 1889. 

 Callista nimbosa Whitfield and Hovey, Bull. Am. Mus. N. Hist., xi., p. 462, 1901. 



Pliocene of the Caloosahatchie beds, at Shell Creek, Alligator Creek, My- 

 akka River, and on the Caloosahatchie River, Florida ; Pleistocene of Simmons 

 Blufif, South Carolina, and North Creek, near Osprey, Florida; recent from 

 the vicinity of Cape Hatteras, North Carolina, south to the Florida Keys 

 (Cuba?), west to Mobile, and the coast of Texas at Matagorda Bay. 



In the fossil specimens the anterior lateral is apt to be shorter and more 

 pustular, the pallial sinus slightly deeper, and the posterior right cardinal 

 shorter and more distant from the nymph, but these differences are not in- 

 variable and I see no reason for separating the two forms even varietally. 



Macrocallista acuminata n. sp. 

 Plate 57, Figure 3. 



Oligocene of the silex beds at Ballast Point, near Tampa, Florida, and of 

 the Chipola beds at Alum Blufif, Chattahoochee River, Florida ; Dall. 



Shell smooth, polished, with faint indications of incremental lines, very 

 inequilateral ; the beaks at the anterior fourth or nearly so ; the lunule nar- 

 rowly cordate, impressed, not sharply circumscribed ; anterior end rounded, 

 base evenly arcuate ; shell sometimes a little rostrate near the posterior end ; 

 posterior dorsal slope slightly arcuate ; posterior end elongated, rather sharp ; 

 hinge normal ; pallial sinus nearly horizontal, pointed behind, in the young 

 reaching forward more than half the length of the shell. Length 28, height 

 18, diameter 9 mm. Fully adult specimens, according to fragments obtained, 

 reach a length of 80 mm. 



This species is not unlike M. reposta Conrad of the Miocene, but is more 

 inequilateral and more acute behind. It probably does not attain the size of 

 the Miocene form, which is often one htmdred and twenty millimetres in length 

 and appears to have a shorter pallial sinus and a more elongate and distant 

 anterior lateral tooth. 



Macrocallista (Chionella) naarylandica Conrad. 



Cytherea marylandica Conrad, Am. Journ. Science, ist Sen, xxiii., p. 343, 1833; Fos. 



Medial Tert, p. 15, pi. ix., fig. i, 1838; Bull. Nat. Inst., ii., pp. 183, 185, 1842. 

 Dione marylandica Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 575, 1863 ; Meek, 



Checkl. Miocene Fos., p. 9, 1864; Whitfield, Moll, of the Miocene Form. N. J., p. 74, 



pi. xiii., fig. I, 1895. 



