292 U>;iTED STATES GEOLOGICAL SUllVEY— TERTIAKY FLOIIA. 



fore, is the only one which might be described separately. As it was foiiiid 

 ill specimens from the same locality, as also its lateral veins, mostly ojjposite, 

 have the same angle of divergence, are straight in passing to the borders, and 

 craspedodrome, it seems really to represent a leaflet of the same species. Fig. 

 5, with a longer petiole, is apparently theli rminal leailet of a compound leaf; 

 the smaller are the lateral ones. But it is not evident if the subdivision of 

 the leaf is tripalmate or pinnate. The comparatively large number of 

 small leaflets rather indicates their relation to a pinnate leaf This species 

 is comparable to Rhus Pyrrha, ditfering by its nerves running straight to 

 the borders and directly entering the teeth, which, moreover, are much 

 larger in the European species. The specimen rejjresented in fig. 4 ot pi. 1 

 is a narrower leaflet, apparently referable to this species. 



Habitat. — Evanston, Wyoming. The specimen of this last tigure is 

 from Middle Park, Colorado {Dr. F. V. Haydeti). 



K li II s III o III b r a n a c «; a , Lesqx. 



Plate LXIV, Figs. G, 7. 



lihm mcmhranacea, Lesqx., Annual Report, 1874, p. 306. 



Leaves ternate ; leaflets membranaceous, oblong, or the lateral ones broadly oral, obtusely poinleil 

 ronnded or subtruncate to a short petiole, irregularly coarsely duplicato-deutate; lateral nerves open, 

 craspedodrome, more or less ramified, the lowest ones curving downward in joining the midrib. 



The sjjecimens represent one leaflet entirely preserved, longer and nar- 

 rower, like the terminal one of a ternate leaf, and part of a lateral one, shorter 

 and broader. The first, two and a half centimeters long, including the petiole 

 (three millimeters), is oblong, with borders cut from the base in comparatively 

 large, obtusely pointed teeth, either simple or with smaller protuberances 

 upon the back; the nervation is distinctly craspedodrome, the secondary 

 veins passing up and scarcely curving to the point of the teeth, and irregularly 

 obscurely dividing in thin branches, joined in the middle of the areas, con- 

 stituting large, indistinct areolae. By the form of the leaflets and the 

 border divisions, this species is closely related to U. Ptjrrhce, Ung., as figured 

 by Heer (Fl. Tert. Helv., pi. cxxvi, figs. 20-28), whose leaves are round, 

 truncate at the base, and broadly dentate, as in our fig. 7. Like R. FyrrhdE, 

 it is also comparable to R. aiwnatica^ Ait., a common species of our present 

 flora, widely distributed over the whole width of the United States, and 

 whose leaflets, extremely variable, have also doubly dentate teeth, and, in the 

 Southern States, a membranaceous consistence. 



Habitat. — Point of Rocks, Wyoming {Dr. F. V. Hayden). 



