288 UNITED STATES GEOLOGICAL SUEVET— TERTIARY FLORA. 



parable to this one. The specimen represented in fig. 9, a mere fragment 

 from another locality, is somewhat different Ijy the lateral nerves more 

 evidently branching and more oblique. The lower veins of fig. 5 have, 

 however, the same characters. The specimen represented in fig. 10 has the 

 lower lateral nerves more open, a difierence unimportant in the determina- 

 tion of species of Juglans. 



Habitat. — Green River, "Wyoming, above fish-beds {Dr. F. V.IIaydefi). 

 The fragment represented in fig. 9 is from Golden, Colorado. It may 

 belong to a different species. 



^ 2. — Lcnjiets crenate or dentate. 



Jiigluns alkulina, Lesqz. 

 Plale LXII, Figs. G-9. 



Juglans alkalina, Lesqs., Annual Report, 1874, p. 308. 



Leaves lanceolate, acuminate, rounded or narrowed in a curve to a sliort petiole ; borders crenu- 

 late; lateral veins distant, mostly alternate, parallel, curved in passing toward the borders, ascending 

 high along them in simple festoons, separated by short intermediate tertiary veins; nervilles iu right 

 angle, strong ; areolation irregulaily quadrate. 



This species, very fine and distinct, is related, by (he facies of the leaves, 

 to the Juglandites of the Sezanne Flora, which have, however, a different 

 character of nervation. The American leaves have the lateral nerves more 

 distant, and their base is not narrowed in the same degree. They are, 

 moreover, much smaller, from five to. twelve centimeters long and from two 

 to four centimeters broad. This species is al.so comparable to J. hUlnica, 

 Ung., presenting, however, the same kind of difference iu the more distant 

 and more oblique lateral nerves, ascending higher along the borders, which 

 are merely crenulate and not denticulate. As seen from the figures, the 

 leaves are more or less unequal at the base, and more or less narrowed 

 or rounded to the petiole; but they do not differ in the essential characters. 

 Variations of the same kind are generally observed upon leaflets of the 

 same species of Juglans and Carya. The bows along the borders are not 

 connected with the teeth by nervilles. 



Habitat. — Allsali Station, Wyoming {Wm. Clehiirn). 



