NO. 2162. FLINT RIVER OLIGOCENE FOSSILS— BALL. 499 



CARDIUM (TRACHYCARDIUM), species indeterminate. 



Locality. — Station 7079, at Mascot Point, on the east bank of the 

 Flint River below the mouth of Blue (or Russell) Spring branch, in 

 chert blocks; Vaughan, Cooke, and Mansfield, 1914. U. S. Nat. 

 Mus. Cat. No. 166768. 



This indeterminable species recalls 0. howdenense Dall, of the Oli- 

 gocene of Bowden, Jamaica, and the Oi'thaulax pugnax zone at Ballast 

 Point, Tampa Bay, Florida, but is not sufficiently perfect to be posi- 

 tively identified. It is, at all events, one of the group exemplified 

 by C. muricatum Linnaeus. 



CARDIUM (LAEVICARDIUM). species. 



Locality. — Station 7096, at Red Bluff, on the west bank of FHnt 

 River, 7 miles above Bainbridge, Decatur County, Georgia; Vaughan, 

 Cooke, and Mansfield, 1914. U. S. Nat. Mus. Cat. No. 166770. 



A small species of this type, not sufficiently well preserved to 

 identify specifically. 



CHIONE BAINBRIDGENSIS, new species. 



Plate 84, figs. 5, 6. 



Shell small, slightly inequilateral, moderately inflated, thin; beaks 

 small, rather prominent, prosoccBlous, with a short lanceolate im- 

 pressed lunule below them; the escutcheon narrow and more elon- 

 gated; sculpture of numerous sharp recurved lamellae, somewhat 

 sparser on the beaks but elsewhere uniformly distributed, and more 

 elevated near the anterior end; radial sculpture of numerous fine 

 threads evenly distributed, with narrower interspaces, strong on the 

 front surface of the lamellae and in the interspaces, but wantmg on 

 the back or concave side of the lamellae; inner margin of the valves 

 finely crenulated; anterior end of the valves rounded, the base 

 prominently arcuate, the posterior end more pointed; hinge as usual 

 in the genus. Height of somewhat defective valve, about 25; 

 length, 35; diameter (double), 18 mm. 



Localities. — Station 7095, on the east bank of Flint River, at the 

 bend near the "Old Factory," about thi-ee-fourths of a mile north- 

 east of the railway station at Bainbridge, Georgia. Also at station 

 7131, at Cherry Chute, 2f miles below Bambridge, in hard residual 

 blocks of limestone; and stations 3381, 7074, 7075, 7078, 7079, 7095, 

 7096, and 7131, at various points on Flint River above and below 

 Bainbridge and within a dozen miles of that town; Cooke and Mans- 

 field, 1914. U. S. Nat. Mus. Cat. No. 166717. 



Each horizon from the Chattahoochee to the recent fauna contains 

 a species of Ohione of this general type, but distinguished by minor 

 differences from the species in the zones above or below. Ohione 

 woodwardi Gupp}^, from the Oligocene of Bowden, Jamaica, is an 

 example of the group. 



