240 UNITED STATES GEOLOGICAL SURVEY— TERTIAKY FLORA. 



Cissiis lob :i to- <r re 11 at a, Lesqx 



Plate XLI, Figs. 1-3. 



Cissus lobaio-crenaia, Lesqs., Annual Report, 1872, p. 396 ; 1873, p. 408.— Schp., Pal. V^g^t., iii, p. 602. 



Leaves subcoriaceous, subcordate at the base, broadly enlarged above it, rapidly narrowed to an 

 obtuse point, cn-nate and sbort-lobed all around, three-nerved from the base; primary and secondary 

 nerves branching, all the divisions craspedodrome. 



These leaves, of medium size, are all broadly enlarged below the middle, 

 lounded, subcordate or truncate to the petiole, broadly deltoid to the point, 

 \vith the borders irregularly creuate or lobed, the projections forced out by the 

 primary and secondary nerves being more marked than those of the branches; 

 the secondary nerves, three or four pairs, are distant, opposite or alternate, 

 strong, though not quite as marked as the primary ones; the nervilles thick, 

 joined in a curve in the middle of the areas, simple l)ut united by nervilles 

 in right angle, forming, by subdivision in the same direction, large, irregularly 

 square meshes. Tliis species is related to C. primceva, Sap. (Fl. Foss. de 

 S^z., p. 100, pi. X, figs. 10, 11; pi. xi, figs. 1, 2). 



Habitat. — Mount Brosse, Colorado (Dr. F. V. Hayden). Not rare at 

 Black liuttes, Wyoming. Not common at Golden, Colorado. 



Cissiis tricuspidata, Heer. 



Plate XLI, Figs. 4-7. 



TUii (Ciseua) tricuspidata Heer, Mioc. Bait. Fl., p. 91, pi. xxviii, figs. 18, 19.— Lesqx., Annual Report, 1872, 

 p. 396. 



Leaves small, snbcoriaceous, enlarged in the middle or above, indistinctly three- or five-lobcd; 

 lobes acute ; borders dentate. 



The lobes of these leaves, referred to Heer's species, are less distinctly 

 n)arked than in the specimen of the Baltic Flora; they are shorter, having 

 about the same character as in the former species, being, however, as well as 

 the teeth of the borders, acute, or at least obtusely pointed; the base of the 

 leaves is also, as in the former species, either narrowed to the petiole or trun- 

 cate-subcordate. Another difference might be pointed out in the distribu- 

 tion of the secondary veins, which, in fig. 19 of Heer's (ioc. cit), have the 

 lowest pair emerging at a short distance above the base of the primary 

 nerve.s. In our figs. 5 and 7, the distance between these veins is consider- 

 able; but in fig. 4 it is already reduced, and in fig. 6, which more closely 

 resembles the Baltic leaves, the disposition of the secondary nerves is the 

 same. It is, however, not possible to make a very exact comparison, as Heer's 

 species is represented only by the half of a small leaf, still smaller than that 



