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149I 



TERTIARY FAUNA OF FLORIDA 



Older Miocene of Easton, Maryland, Conrad; Miocene of Calvert County 

 and the Choptank River, and at and near Plum Point and Reeds, Maryland ; 

 also in the Miocene of Virginia, Conrad. 



This is an abundant species of rounded trigonal shape with moderately ele- 

 vated, flattened beaks, sculptured with strong, concentric ridges, the rest of the 

 disk remaining nearly smooth. The Astarte castrana of Glenn from an exami- 

 nation of the types appears extremely similar to the adolescent individuals of 

 this species. 



Astarte (Ashtarotha) undulata Say. 



Astarte undulata Say, Journ. Acad. Nat. Sci. Phila., iv., p. 150, pi. ix., fig. 5, 1824; Con- 

 rad, in Morton, Syn. Org. Rem., App., p. 3, 1834; Fos. Medial Tert., p. 41, pi. x.n:., 

 fig. 7, xxi., fig. 4, 1840; Proc. Acad. Nat. Sci. Phila., xiv., p. 578, 1863; Tuomey and 

 Holmes, Pleioc. Fos. S. Car., p. 70, pi. xx., fig. 12, 1857; Emmons, Geol. Rep. N. Car., 

 p. 289, fig. 213, 1858; Meek, Checkl. Inv. Fos. Miocene, p. 7, 1864. 



Astarte thisphila Glenn. 



Miocene of Maryland at Jones Wharf, Calvert Cliffs near Governor's Run, 

 and near Greensboro' ; of Virginia at and near Petersburg, City Point, and 

 Grove Wharf on the James River, the upper bed on the York River, and at 

 various localities on the Nansemond River, near Suffolk ; of Duplin County, 

 North Carolina, at the Natural Well and Magnolia, and in the Sumter Miocene 

 of South Carolina. 



The variety vaginulata was obtained at Grove Wharf on the James River, 

 Virginia. 



This is the most abundant of our Miocene species, short, high, with flat- 

 tened gibbous umbones and a few broad undulations, the ventral third of the 

 shell smooth or faintly striated. The outline is quite variable and the inner 

 margins crenulate. It recalls the A. bipartita Sowerby from the Suffolk Crag 

 of England. 



Astarte undulata \ar. vaginulata Dall. 



This differs from the typical undulata in being more triangular, with a 

 straighter base, smaller, flattened area on the beaks, with finer concentric sulca- 

 tion which extends in most specimens to the base of the shell, though some- 

 what irregularly. 



The A. thisphila Glenn appears from an examination of the types to be 

 founded on adolescent specimens of A. undulata, which are slightly more com- 

 pressed, relatively, than the perfectly adult shells. 



