Geological Survey of Alabama. 41 



smooth ; within both valves eight raised prominent rounded ribs, becom- 

 ing obsolete as they approach the beak. 



Locality. Matthews' Landing, Ala. 



Seems to unite Pleuroiiectia and Pecten. One specimen shows con- 

 centric strise and ribs in the younger part of the shell, these becoming 

 obsolete toward the ventral margin. The enlarged figure gives a view of 

 the interior. 



ANOMIA EPHIPPIOIDES, GABB., VAR., LISBONENSIS, new var. PI. 4, 



fig. 6. 



Shell thin, pearly, suborbicular; upper valve smooth, slightly Wrinkled 

 on the umbo ; lines of growth distant, hinge line doubly sigmoid, the 

 extremities winged. Muscular scars indistinct. 



Locality. Lisbon and beds at base of Claiborne Bluff. 



The type is externally marked with broad radiating bands of color. 

 On comparison with A. ephippioides, Gabb., it appears much larger and 

 more transverse; that species is not smooth externally, and is often plicate. 

 It occupies the same horizon however. 



OSTREA JOHNSONI, n. sp. PL 6, fig. 6. 



Shell large, thick ; both valves convex ; beaks pointed in lower valve ; 

 breadth of shell greater than length ; both valves strongly plicate, gen- 

 erally with six folds, the plications becoming very deep with age, the 

 concave part between the two basal folds, running out into a long curved 

 tongue ; surfaces strongly laminated, laminae terminating at edge of shell ; 

 attachment scar not visible ; ligamental area with a rather deep trans- 

 versely striated furrow in the lower valve, shallower and broad in the 

 upper; muscular scar, large nearest the base and posterior margin; curved, 

 spatulate, nearly straight on upper side. 



Locality. Monroe County Calc. Sand-bed, Claiborne and Lisbon, 

 Ala., also Newton, Miss. 



Named in honor of Lawrence C. Johnson, of the U. S. Geological 

 Survey. This form seems to be confined to the Lower Claibornian above 

 the Buhrstone. 



