Kirchner — The Fossil Flora of Florissant, Colorado. 183 



the lateral nerves, toward the outer side of the leaf, seem to 

 form a fine net-work which runs parallel with the margin of 

 the leaf and sends off minute branches into the points of the 

 teeth. The tertiary nerves are scarcely discernible. This 

 leaf does not answer to the description of any of the five 

 species enumerated by Lesquereux. It seems more closely 

 allied to some form of Z. Ungeri of Heer. 



Rhamnus. 



9. Rhamnus ellipticus, sp. nov. (Plate XV. fig. 3). 



Leaf simple, subcoriaceous, elliptical ; margin entire ; 

 primary nerve thick and straight; secondary nerves close, 

 numerous, nearly parallel, camptodrome ; areolation quadrate. 



The base of this leaf is wanting. The leaf is 2 centimeters 

 broad and about 5 centimeters long. The secondary nerves, 

 given off at an angle of 30°-40°, are nearly straight and some- 

 times incomplete. The leaf is analogous to that of R. inter- 

 medins, Lesqx., but the midrib is thinner and the secondary 

 nerves in astomosing near the margin are more looped than 

 those of the leaf described by Lesquereux. 



JUGLANDACEAE. 



JUGLANS. 



10. Juglans Crossii, Knowlton. (Plate XIV. fig. 1). 



Juglans denticulata, Heer. Lesqx. Ann. Rep. U. S. Geol. Surv. 1871: 

 298.— Tert. Fl. 7 : 289. PI. L VIII. Jig. 1 . 



Leaves long-lanceolate, narrowed to a point and denticulate 

 upwards ; either rounded to the petiole or gradually attenuated 

 to it (Lesquereux). 



The specimen is fragmentary, but enough of the plant is 

 present to show the necessary characteristics. Portions of 

 two leaflets attached to the stem are shown in the fragment. 

 One leaflet which seems to be terminal has a petiole whose 

 length is three centimeters; most of this leaflet is wanting; 

 its base is unequal and attenuated to the petiole. About half 

 of the second leaflet is present. It was probably 10-12 centi- 

 meters long and 4 centimeters wide, lanceolate or elliptical, 



