112 



Leaves and fruits of uncertain affinity. 

 Phyllites betul^folius, Lesqx., PI. xxviii, Figs. 4-7. 



Leaves small, mostly in fragments, round-ovate, truncate at the top, narrowed to the base by a 

 round curve ; borders dentate ; nervation pinnate, irregular, craspedodrome. 



Phyllites betulcefolius, Lesqx., Transactions of the American Philosophical 

 Society, vol. xiii, p. 430, PI. xxiii, Figs. 2-4. 



These fragments, though far different iu form and size, appear to belong 

 to the same species. All the leaves are marked on the borders by short 

 teeth, turned outside ; the secondary veins, at various distances, are more or 

 less open, mostly branching, entering the teeth by their points or those of 

 their divisions, and joined by strong flexuous nervilles, perpendicular to the 

 veins and undulate. The consistence of the leaves is thickish. They appear 

 to have been petioled, at least from the narrowing of the base of the leaves in 

 Figs. 5, 7, above the line of disruption. 



Habitat. — Fort Harker, Dr. Leconte ; the fragment of Fig. 4 is from Ne- 

 braska, Prof. James Hall. 



Phyllites rhomboideus, Lesqx., PI. vi, Fig. 8. 



Leaf rhomboidal, broadly cuneate to the base, more obtusely narrowed and undulate from the mid- 

 dle to an obtuse short point ; nervation five-palmate from the base, the two inner lateral veins curving 

 up at a very acute augle of divergence and aerodrome, or nearly reaching the point of the leaf, branch- 

 ing outside, the external veins following the borders up to the middle of the leaf, where they anasto- 

 mose with branches of the first pair. 



Ficus (?) rhomboidea, Lesqx., American Journal of Science and Arts, loc. cit., 

 p. 96. 



A remarkable leaf, which, by its form and nervation, somewhat resem- 

 bles the leaf of a Smilax, a Paliurus, or a Populus, and which, by its thick 

 consistence and thick nervation, is different from any species of these genera. 

 Its form is nearly exactly rhomboidal, being, however, more acutely cuneate 

 and entire from the enlarged jjart, the middle, to the base than to its obtuse 

 point, where it passes by undulations. Its five-palmate nervation is from a 

 slightly enlarged base, apparently the top of a broken petiole. The general 

 form of the leaf is like that of Populus arctica, Heer, as represented in Flora 

 Arctica, (1, PI. v, Fig. 3;) — even the direction of the five primary veins is about 

 the same ; but the veins are thicker, as is also the texture of the leaves, and 

 these veins are less branching. Moreover, the base of the leaves in the 

 Arctic species is always more enlarged, generally round or truncate. The 



