92 UJStlTED STATES GEOLOGICAL SURVEY— TERTIARY FLORA. 



CYPERACEiE. 



CYPERUS, Linn. 



Cyperns Ciiavaneusis, Heer. 



Plate IX, Figs. 1, 2. 



Cyperua Chavanensis, Heer, Fl. Tert. Helv., i, p. 72, pi. xxii, fig. 7, xxviii, fig. 1, cxlvi, fig. 22.— Sism., 

 Mater., p. 23, pi. vii, figs. 5, 6.— Ett., Fose. Fl. v. Bil., p. 26, pi. vi, fig. 3.— Lesqx., Annual 

 Report, 1871, p. 300. 

 Leaves large, obscurely carinate in tbe middle, nerved ; primary nerves variable in distance, inter- 

 mediate veins tbree or more, crossed in right angle by transverse veinlets. 



The fragment (fig. 1) represents apparently part of a large leaf of this 

 species, like fig. 1 c, pi. xxviii, of Heer, loc. cit. It has, however, no trace of 

 a middle nerve or of a carina, and the nerves are somewhat unequal in dis- 

 tance. It is the same in fig. 2, which has the primary nerves twice as dis- 

 tant, and seems to represent part of a stem of the same species. In both 

 these specimens, the cross-veinlets are discernible by a strong glass. This 

 species is apparently very variable. Sismondi {loc. cit.) represents a leaf 

 narrower than our fig. 1, but indistinctly keeled, and the distance between 

 the primary veins is the same as in our specimen; in d'Ettingshausen (Bil. FL), 

 the same character of nervation is remarked ; our specimen (fig. 2) has the pri- 

 mary nerves at a greater distance, double than that indicated in fig. 1 ; the 

 spaces of different shades of color resemble the fragment figured by Heer 

 (pi. xxii, fig. 7). These analogies are uncertain and obscure indeed, and I 

 should perhaps have done better in leaving undescribed these fragments, as 

 I have done for others formerly ascribed to this genus. They may be used 

 for comparison with specimens of other localities. One from Evauston, 

 for example, represents a flattened stem, one centimeter broad, without 

 any articulation, obscurely striate, with primary veins distinct and variable in 

 distance, and veinlets thin and joined by cross-branches. It has been also 

 described as referable to the same Cyperus. 



Habitat. — Evanston, below the coal {Dr. A. C. Peak); Green River 



group {Dr. F. V. Hayden). 



CAREX, Mich. 



Carex Bcrtlioudi, Lesqz. 



Plate IX, Figs. 3, 4. 



Carex Berthoudi, Les<ix., Annual Report, 1872, p. 377. 



Leaves flat, marked by an obscure middle nerve and bordered by more distinct ones; intermediate 

 veins thin, close, sometimes obsolete ; seeds ovate or broadly oval, flattened, with oval more or less 

 pointed aud broader perigyuia. 



The leaves are all in small fragments, from the nature of the matrix 



