298 PROCEEDIXGS OF THE XATIOXAL MUSEUM. vol.48. 



The present species is named from its resemblance to the leaves 

 of the existing Salix virnindlis Linnaeus, from which, however, it is 

 perfectly distinct, as it seems to be also from existing American 

 species of Salix. It is represented by three specimens from Hickman 

 and is present in considerable abundance in the late Pleistocene of 

 North Carolina. 



Type.— Cat. No. 34963, U.S.X.M. 



Genus POPULUS Linnaeus. 



POPULUS, species. 



Characteristic staminate aments of a species of Populus are not 

 uncommon in the clays at Hickman. They are 3 or 4 inches long 

 and probably represent either Populus TieteropTiylla Linnaeus or 

 Populus deltoides Marsh, presumably the latter species, since they 

 are hardly stout enough to be referred to the former. They are not 

 well enough preserved to show the details of their organization, but 

 they do show clearly the bracts and the subtended masses of stamens. 



Order FAGALES. 



Family BETULACEAE. 

 Genus BETULA Linnaeus. 



BETULA NIGRA Linnaeus. 



Betula nigra Linnaeus. Kxowltox, Amer. Geol., vol. 18, 1896, p. 371. — Berry, 

 Journ. Geol.. vol. 15. 1907. p. 341; Amer. Nat., vol. 41, 1907. p. 692, pi. 2, 

 figs. 2-A; vol. 43, 1909, p. 435; Amer. Journ. Sci., ser. 4, vol. 29, 1910, p. 393. 



The river birch is not uncommon in our fluvial Pleistocene deposits, 

 having been already recorded from West Virginia , Virginia, North 

 Carolina, Georgia, and Alabama. It is represented by leaves in the 

 Hicknian Bluff. In the existing flora it is a distinctly mesophytic 

 type of stream and lake borders with a wide range extending from 

 Massachusetts to Iowa and southward to Florida and Texas. 



BETULA, species. 



The Hgnifled remains of catkins are very common both at Columbus 

 and Hickman. Similar remains were collected by Owen and Les- 

 quereux from the Chalk Banks below Columbus and were referred 

 to by the latter author as " catkins of Alnus or Betula" 1 . After 

 careful comparisons I have concluded that they represent the mature 

 pistillate catkins of Betula, which, although the scales are normally 

 deciduous, often remain intact, especially if not thoroughly mature 

 and dry, and are readily preserved in river muds. 



1 Lesquereux, Amer. Journ. Sci., ser. 2, vol. 27, 1S59, p. 365. 



