700 GEOLOGY OF THE YELLOWSTONE NATIONAL PARK. 



FACUCE.E. 



Faous antipofii Al)icl). 



Far/iis antipofii Abicb. Lesquereus : Aiiu. Kept. V. S. Geol. and (ieog. Sniv. Terr.. 1S72 

 (1873), p. 403. 



Llcntiiied bv Lesquereux, l)iit not since observed. 

 IIal)itat: "Elk Creek, near Yellowstone River; A. C. Peale, Josejjh 

 Savage, and O. C. Sloane." 



Fagus undulata n. sp. 



PL LXXXV, flgs. 4, 5. 



Leaves small, of verv firm texture; ellijitical with a broadly wedae- 

 shaped base and apparenth' olitnse apex; margin regularly undulate- 

 toothed, the teeth Ijeing regularly rounded and separated by similarly 

 rounded sinuses; midrib strong, straight; secondaries numerous, ojjposite, 

 parallel, unl>ranched, all entering the obtuse teeth; nervilles very numerous, 

 at right angles to the secondaries, usually bi-oken and anastomosing, 

 although sometimes ii'regularlv percurrent: Hner nervation ])roducing 

 small, irregularly quadrangular areolation. 



This tine species is fortunately represented b}' several very jierfectly 

 preserved examples, the two tigured showing both the liasal and apical por- 

 tions. They A-arv in length from 6 to 10 cm. and in width trom '1.1') to 4 

 cm. The maro-ins are verv regularlv imdulate-toothed, the sinuses being 

 almost an exact reverse of the nearest teeth. The wedge-shaj)ed base is, 

 however, without teeth for a short distance. The secondaries are at an 

 angle of about 45°. They are parallel, and all enter the obtuse teeth. All 

 of the finer nervation is beautifidly preserved and is seen to be irregularly 

 quadrangular. 



This species does not approach closely to any living- species known to 

 me. It is perhaps nearest to certani forms of the common American F. 

 ferruginea Ait., but the liA'iug- form differs in being proportionatel}' broader, 

 and when toothed has sharp teeth, c[uite like Castanea, and pointing vipward. 



Among the 80 or more fossil species that ha\e Ijeen described from 

 various parts of the world, there are several that our species more or less 

 closely resembles. Of these, F. dentata Gopp., as identitied by Heer' in the 



' Fl. Foss. Aict., Vol. I, i>. 10(1, PI. X, ligs. 76, 9. 



