60 THE LATER EXTINCT FLORAS OF NORTH AMERICA. 



of Frazer River, and appear in PI. XXI, fig. 10, of the Atlas which 

 accompanies the Greology of the Wilkes Exploring Expedition. Upon the 

 same slab are seen the branches of Glyptostrobus Ungeri (?), the branchlets 

 and cone of Taxodium disticJmm mi'ocenum, leaves of Mhamnus Gaudini (?), 

 and Smilax cyclophylla Newb. Some of these are reproduced on PI. LIV, 

 fig. 3 (Carpinus and Smilax); PI. LV, figs. 3 to 6 (Glyptostrobus, Tax- 

 odium, Carpinus). Very few fossil plants were brought from this locality, 

 but they seem to represent a horizon somewhat different from that which 

 has supplied any other specimens in the collection. Leaves of various 

 kinds appear to be exceedingly abundant and beautifully preserved there, 

 and it is to be hoped that the locality may be visited by some other 

 collectors, who shall bring us a fuller representation of its riches. 



Formation and locality : Tertiary (Eocene?). Birch Bay, Washington. 



Corylus Americana fossiijs Newb. 

 PI. XXIX, figs. 8-10. 



Corylus Americana Walt. Newb. Ann. N. Y. Lye. Nat. Hist., Vol. IX (April, 

 1868), p. 59; Ills. Cret. and Tert. PI. (1878), PI. XIV, figs. 8-10. 



Among the variety of specimens of the leaves of C. Americana with 

 which I have compared these fossils, there are some which, if fossilized, 

 would form impressions absolutely undistinguishable from them, and I 

 have therefore found it impossible to fix upon any characters by which they 

 can be separated. As compared with the fossils which I have referred to 

 C. rostrata, these leaves are a little more rounded in outline, the nervation 

 somewhat more open and delicate, the marginal teeth more nearly equal in 

 size, and more obtuse. 



Of all the species of Corylus, living or fossil, which have been described, 

 there is none of which the leaves so much resemble the ones under consid- 

 eration as do those of C. Americana. 



Collected by Dr. F. V. Hay den. 



Formation and locality: Tertiary (Fort Union group). Fort Union, 

 Dakota. 



