DESCRIPTIONS OF SPECIES. 00 



wedge-shaped than the latter. Unfortunately the specimen represented 

 in fig. 4 has the base and summit broken away, and the identification is 

 therefore not absolutely certain, but as it was obtained in the same region 

 where Dr. White collected the narrow-leaved willows before us there is 

 every probability that they are the same. 



Whether the narrow-leaved willow of the Green River beds is identical 

 with that found in the so-called Miocene or Oeningen is, however, an open 

 question. That both are willows there can be no reasonable doubt, but the 

 leaves of so many species of willow are narrow lanceolate with tapering- 

 bases and summits that it is quite impossible to be sure of an identification 

 based on a mere general resemblance. All we can say, therefore, is that 

 during the deposition of the Green River Tertiary beds willow trees grew 

 on the banks of the rivers and lakes of that region, having long, narrow 

 leaves with simple margins and undistinguishable by any well-marked 

 character from those obtained from the Tertiary of Oeningen. 1 



Formation and locality: Tertiary (Green River group). Green River, 

 Wyoming. 



Salix cuneata Newb. 



PI. II, figs. 1, 2. 



Ann. N. Y. Lye. Nat. Hist., Vol. IX (April, 1868), p. 21; Ills. Cret. and Tert, PI. 

 (1878), PI. I, figs. 1, 2 [fig. 1 under Salix Meehii\. 



"Leaves of medium size, sessile or short-petioled, entire, elongate, 

 narrow, acute at both ends, broadest toward the apex, gradually narrowed 

 below to the base; medial nerve distinct; secondary nerves delicate, 

 springing from the midrib at an angle of about 20 degrees near the 

 middle of the leaf, 15 to 20 degrees below, straight and parallel near 

 the bases, gently arched above and inosculating near the margins." 



Collected by Dr. F V. Hayden. 



This species presents some marked characters by which it may be dis- 

 tinguished from those before described. It is true that the variations of 

 form among the leaves of our recent species of willow are almost infinite, 

 and even in the same species and from the same tree leaves may be obtained 



i A comparison of our figure with those of Heer and Lesquereux leads me not only to doubt 

 their identity, but to think that ours is more hkely to be a Eucalyptus. The marginal nervation is 

 certainly more characteristic of the latter genus than of Salts.— A. H. 



