Ill 



meshes ; the veins and their divisions curve along the borders in a succession 

 of short flexures. This nervation is somewhat like that of some leaves of 

 Juglans of the European Tertiary: for example, Juglans latifolia, Heer, (Flor. 

 Tert. Helv., Ill, p. 88,) especially as marked in PI. cxxix, Figs. 3, 6, and 9. 

 However, the reference of these leaves to Juglans is far from positive, the 

 nervilles being more irregular and the veinlets more irregularly divided than 

 in any species of Juglans. A more analogous nervation to that of this species 

 is remarked in some species of Rhus, as in R. metopium, which has coriaceous 

 leaves, slightly cordate, and of forms somewhat resembling those of the fossil 

 leaves. 



Habitat. — Decatur, Nebraska, Hayden ; a large number of specimens. 



Phyllites rhoifolius, Lesqx., PI. xxii, Figs. 5, 6. 



Leaves coriaceous, lanceolate, penninerve, irregularly obtusely crenate ; medial nerve thick ; sec- 

 ondary veins parallel, camptodrome. 



Phyllites rhoifolius, Lesqx., American Journal of Science and Arts, loc. cit., 

 p. 101. 



The two fragments of leaves, represented in the figure, are of very un- 

 certain relation. As seen in Fig. 6, the leaves of this species appear to 

 have been enlarged on one side and somewhat lobate at the base, or of an 

 irregular form. As in our Rhus toxicodendron, the secondary veins are thick, 

 on a broad angle of divergence, curving along the borders, where they unite 

 with oblique obscure nervilles. I compared it, for the nervation, (in the 

 journal quoted above, 2, xlvi, 1868,) to R. cotinoides, one of the numerous 

 varieties of the poison-ivy. 



Habitat. — Lancaster County, Nebraska, Hayden. 



Prunus cretaceus, Lesqx., PI. xxiii, Figs. 8, 9. 



Drupe ovate, obtusely pointed, smooth, grooved on one side to the middle, notched at the enlarged 

 obtuse base. 



Prunus cretaceus, Lesqx., American Journal of Science and Arts, loc. cit., 



p. 102. 



The form of this small, hard fruit is like that of the drupe of a plum, or 

 of a large cherry. Another nutlet of about the same form, but compressed 

 and flattened, is imbedded in the stone, its back and part of the sides only 

 being visible, as seen in Fig. 9. 



Habitat. — Same locality as the former. 



