40 DESCRIPTION OF SPECIES. 



for the distance and the ramification of the secondary nerves; the lower 

 ones only are more open and more bowed in passing to the borders, the 

 lowest pair being nearly at right angles to the thick medial nerve. The 

 specimen is No. 1175 of the U. S. National Museum. 



Quercus poranoides, Lesqx. 

 "U. S. Geol. Rep.," vi, p. 66, pi. xxx, fig. 9. 



The generic relation of this fragment, like that of the preceding, is 

 not positively ascertained. 



Quercus Morrisoniana, ep. uov. 

 Plate XVII, Figs. 1, 2. 



Leaves of medium size, coriaceous, petiolate, ovate-lanceolate, acuminate ; medial 

 nerve strong ; secondary nerves numerous, alternate, curved in passing to the borders, 

 camptodrome, simple, or some of them forking near the entire borders. 



The species is related by its characters, shape, size, facies of the leaves, 

 and nervation to the Miocene Quercus' neriifolia, A. Br. The midrib is 

 strong, prolonged into a petiole 1J centimeters long. The lower veins are 

 slightly more open than the upper; all are nearly parallel, variable in 

 distance, more or less bowed in passing to the borders, which are very 

 entire. The leaves average 10 to 12 centimeters long, 3 to 3 J centimeters 

 broad in the middle where they are the widest, gradually narrowing in a 

 curve to the base and slightly decurring to the petiole. 



The embedding material is a sandstone too coarse for the preservation 

 of the areolation; flexuous nervilles, transversely decurrent, are more or 

 less distinct. By this character the leaves are related to Q. nervosa, Sap., 

 "Et.," ii, i, p. 86, pi. iii, fig. 12. 



Hah. — Base of the mountains, near Morrison, Colorado. //". C. Beckwith. 



Quercus salicifolia, Newby. 



"Notes on Ext. Fl.," p. 24 ; " Illustr.," pi. ii, fig. 1. 



Leaves petiolate, smooth, thick, entire, abruptly pointed at both ends; medial 

 nerves strong, straight or flexuous; secondary veins unequal in size, strong near their 

 base, becoming finer, flexuous, and branching toward the borders, where some of them 

 inosculate by irregular curves while others terminate in the margin. 



The facies of the leaf and the alternation remarked by the author of 

 large with smaller secondary veins, a character essentially pertaining to the 

 willows, seem to justify the reference of this leaf to Salix. The coriaceous 



