FOSSIL FLORA. 699 



Besides these, belonging to the genus Betula, there are a number of 

 others more or less resembling this leaf; e. g., Alnus carpinoides Lx., 1 from 

 Bridge Creek, Oregon, and Celastrus ovatus Ward, from the Fort Union 

 group of Montana. 



Among living species this appears to be closest to Betula lutea Michx., 

 but even this is somewhat remote. In the future it may be thought best 

 to place this fossil species under some other genus, for which, no doubt, 

 reasons may be found, but for the present it seems best to place it in Betula. 



Betula mqualis Lx., 2 from the Auriferous gravels of California, is evidently 

 closely related; but this differs in being much narrower, more wedge-shaped 

 at base, and in having fewer and smaller teeth. B. prisca Ett, as figured by 

 "Ward 3 from the uppermost Fort Union, near the mouth of the Yellowstone 

 River, is similar but much smaller. 



This species is named in honor of Prof. J. P. Iddings, of the University 

 of Chicago, who pointed out the locality at which it was first collected. 



Habitat: Yellowstone River, one-half mile below the mouth of Elk 

 Creek, top of bluff; collected by F. H. Knowlton, August, 1888. Hill 

 above Lost Creek, bed No. 2; collected by F. H. Knowlton, August 5, 1888. 



Corylus macquarryi (Forbes) Heer. 



PI. LXXXVI, fig. 3. 



Corylus macquarryi (Forbes) Heer: Urwelt d. Schweiz, p. 321, 1865. 



The collection contains a single well-preserved specimen that is referred 

 with some little hesitation to this well-known species. It has the proper 

 shape, including the heart-shaped base and identical nervation, but differs 

 slightly in the marginal dentation. In the typical form the margin has 

 numerous rather small, sharp, upward-pointing teeth, while the one under 

 consideration has fewer, rather blunt teeth. It may not be the same, but 

 rather than make a new species I have referred it to G. macquarryi. 



Habitat: Fossil Forest, middle stratum, Hague's Yellowstone National 

 Park collection (No. 1220); collected by Arnold Hague, September 24, 1884. 



'Op. cit., p. 243, PL LI, fig. 5. 



-.Mem. Mas. Comp. Zoiil., 1878, p. 2, PI. I, figs. 2-4. 



-Types of the Laramie PI., PI. XIV, fig. 2. 



