FOSSIL FLOKA. 699 



Besides these, lieloiiging- to the genus BetiUa, there are a number of 

 others more or less resembling- this leaf; e. g., Alnu.^ carpimides Lx./ from 

 Brido-e Creek, Oregon, and Celastrus ovatns Ward, from the Fort Union 



group of Montana. 



Among li^nng species this appears to be closest to Bdnhi hifea ^lichx., 

 but even this is somewhat remote. In the future it may l)e thought best 

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

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



Betula (pquaUs Lx.,' from the Auriferous gravels of California, is evidently 

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

 at base, and in liaving fewer and smaller teeth. B. piisca Ett., as figured l)y 

 Ward^ from the uppermost Fort Union, near the mouth of the Yellowstone 

 River, is similar but nuich smaller. 



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

 of Chicago, wlro pointed out the locality at wdiich it was first collected. 



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

 Creek, top of blufi-'; collected by F. H. Knowlton, August, 1888. Hill 

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



CoRYLUS MACQr.\RRYi (Forbes) Heer. 

 PL LXXXVI, tig. 3. 



Coviilus macquarryi (Forbes) Heer: Urwelt d. Schweiz, p. 321, 1805. 



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 (me under 

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

 rather than make a new species I have referred it to ('. iiiaajxarrfii. 



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

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



'Op. (it., p. 243, PI. LI, fig. 5. 



- Meiu. JIus. Comp. Zool., 1878, p. -', PI. I, figs. l'-4. 



'Types of the Laramie FL, PI. XIV, fig. 2. 



