510 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.51. 



in coralliferous chert; and at station 7079, on the east bank of Flint 

 River at Mascot Point, below the mouth of Blue (or Eussell) Spring 

 branch; Vaughan, Cooke, and Mansfield, 1914. U. S. Nat. Mus. 

 Cat. No. 166789. Also from the Oligocene marl of the Chipola Kiver, 

 Calhomi Comity, Florida, and in the Orthaulax pugnax zone, at Bal- 

 last Point, Tampa Bay, Florida. 



STROMBUS, species indeterminate. 



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. 166790. 



An indeterminate cast of a species of Strombus was obtained at the 

 above locality. 



BITTIUM SIUCIUM, new species. 



Plate 86, fig. 11. 



Shell small, slender, with a distinct, not channeled, suture and, in 

 the decollate specimen, about eight nearly fiat-sided strongly sculp- 

 tured whorls; axial sculpture of about, on the penultimate whorl, 

 24 narrow low riblets, with about equal interspaces, overridden and 

 obscured by the strong spiral sculpture. The latter consists of four 

 spiral cords near the apex, rather more slender than the ribs, with 

 about equal interspaces, but later they become broader and stronger, 

 the interspaces relatively somewhat narrower, the cords where they 

 cross the ribs are swollen rather than nodulous, and the interspace 

 separating the anterior and posterior pairs is deeper and more chan- 

 neled than the others; on the last whorl the ribs are feebler than 

 previously and the periphery is formed by the fourth cord. On the 

 base follow four more crowded simple spirals, the anterior a little more 

 prominent than the others and separated by a wider space from a sort 

 of keel and several finer threads wliich encircle the vicinity of the 

 canal and the canal itself. The latter is short and shallow; the aper- 

 ture is defective; the apex of the shell is wanting. Length of shell, 

 20; of last whorl, 7; diameter of decollation, 3; of the base, 7 mm. 



Locality. — Station 7075, on the east bank of FHnt River, about lOJ 

 miles below Bainbridge, and just above Lambert Island; Cooke 

 and Mansfield, 1914. U. S. Nat. Mus. Cat. No. 166729. 



DIASTOMA GEORGIANA, new species. 



Plate 86, fig. 6. 



Shell small, slender, acute, the nucleus small, pointed, of about 

 two whorls, obscured by adherent matrix, with about 10 subsequent 

 gradually enlarging whorls ; sculpture coarse, axiaUy sculptured with 

 about (on the penultimate whorl) a dozen rounded ribs with subequal 

 interspaces, these ribs broader and more prominent anteriorly; 



