694 GEOLOGY OF THE YELLOWSTONE NATIONAL PARK. 



SALICACE,E. 



POPULUS GLANDULIFEKA Heer. 



PI. LXXXIV, fig. 1. 



Papains gland til if era Heer. Lesquerenx : Cret. and Tert. Fl., p. 226, PL XLYIa, figs. 

 3, 4. Ward: Types of the Laramie Fl., p. 10, PI. IY, figs. 1-4. 



The collection contains 3 specimens with very tine rounded or sharp 

 teeth, that are referred without hesitation to this species, as figured by 

 Lesquerenx and Ward, from the tj r pical Fort Union group of the lower 

 Yellowstone. The best of these is figured. 



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

 Creek; collected by F. H. Knowlton, August, 1888. 



Popuxus speciosa Ward. 



PI. LXXXIY, fig. 3. 

 Populus speciosa Ward: Types of the Laramie FL, p. 20, PI. V, figs. 4-7. 



The Park collection contains something over 50 specimens that are 

 referred to this species. They are very perfectly preserved, and the petiole 

 is in some cases 8 cm. in length. There can be no question as to their 

 correct reference to the Fort Union species. I should also incline to refer 

 to this species certain of the leaves described as Populus amblyrhyncha Ward 

 and P. oxyrliyncha Ward, from the same beds. The very slight differences 

 separating these forms seem hardly to be worthy of specific rank. 



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

 Creek; collected by F. H. Knowlton, August, 1888. 



Populus zaddachi Heer. 



Populus zaddachi Heer: Fl. Tert. Helv., Vol. Ill, p. 307. Lesquerenx: Cret. and 

 Tert, Fl., p. 158, PI. XXXI, fig. S. 



A few specimens were obtained that must be referred to this species. 

 Habitat: Late acid breccia, Pyramid Peak; collected by Arnold 

 Hague, 1897. 



