196 UNITED STATES GEOLOGICAL SURVEY— TERTIARY FLORA. 



genus, like that of Ficus ferrvginea, for example, as it is represented, by 

 impression of a living specimen, in Ett., Bil. Fl., pi. xix, figs. 3 and 4. The 

 lateral nerves, on an open angle of divergence of nearly 70°, gradually curve 

 upward in coming near to the borders, and follow them in simple festoons, 

 anastomosing by nervilles. The nervilles, somewhat strong and in right angle 

 to the midrib, are oblique (o the secondary veins, generally branch in right 

 angle also in the middle of the areas, and subdivide in the same direction, 

 composing an ultimate, very small, irregularly quadrate areolation. Though 

 the base is destroyed, its rounded form is surmised from the direction of the 

 lower line of the fragment; and, by what is left of the border toward the 

 point, it appears to have been acuminate. The leaf is runcinate on the 

 surface. It does not compare to any fossil species, as far as I know at least. 

 The middle nerve, though somewhat strong and deeply impressed into the 

 stone, is not as thick by far as in the former species, to which it has, how- 

 ever, a certain degree of relation, especially to figs. 2 and 3, pi. xxix. It is 

 remarkable that so many leaves of the same type are found together. 

 Habitat. — Same as the former {Dr. F. V. Hnyden). 



Ficus irregularis, Lesqx. 

 Plate XXXIV, Figs. 4-7; LXIII, Fig. 9. 

 Ulnms T irregularis, Lesqx., Annaal Keport, 1872, p. 378. 



Leaves large, coriaceous, very entire, broadly ovate or oval, constricted upward to an acumen, 

 rounded or cuneiform to the inflated petiole ; middle nerve narrow : lateral veins thin, in an acute angle 

 of divergence, simply camptodrome, irregularly forking. 



The secondary veins of this species are close, sixteen pairs in a leaf, part 

 of which only, eight centimeters long, is preserved, averaging 40° in their 

 angle of divergence from the middle nerve, curving slightly downward at 

 their point of insertion, generally simple; some of them only abnormally fork- 

 ing from near the base, and joined by thin, numerous, somewhat oblique 

 fibrillse. The specimens which I had for my first examination (figs. 4 and 

 5) have the borders destroyed, and I was therefore very uncertain to what 

 genus these leaves should be referred, their nervation being analogous to that 

 of Ulmus, especially in the peculiar forking of some of the lateral nerves 

 The specimens (figs. 6 and 7) found later contradict this reference. The bor- 

 ders perfectly entire, the simply camptodrome nervation, are characters at vari- 

 ance with those of Ulmus. On the other hand, the close, numerous, parallel, 

 and equidistant camptodrome secondary nerves are remarked in species of 

 Ficus, in F. Jyiix, F. muhinervis, for example, and the enlarged petiole. 



