DESCRIPTION OF SPECIES— GRAMINEiE. 91 



than those of the former, and therefore a smaller plant. These leaves, from 

 one to two centimeters wide, linear, obtuse or obtusely mucronate, are nerved ; 

 in the length, with primary veins one millimeter distant, separated by three \-^ 

 thin, obsolete, secondary ones. The substance of these leaves is hard and 

 somewhat thick, the epidermis thin but corneous-like, covering the veins and 

 veinlets, and rendering these indiscernible. This epidermis is, however, some- 

 times separable from the surface, and then the veinlets are distinctly visible. 

 The specimen of our fig. 12 has the same size and appearance as that of Heer 

 (loc. cit., fig. 12). But in fig. 12 h of the Swiss author, the intermediate second- 

 ary veins are marked more numerous, or by six, though the primary ones are 

 at the same distance, of one millimeter, as in our specimens. As the author 

 remarks that the veinlets are obsolete, and as in the corticated specimens of 

 ours the veinlets appear more numerous, on account of their indistinctness 

 when seen through the epidermis, it is possible that the number of these 

 secondary veins has not been distinctly seen, or that, as it is the case with 

 Phragmites CEningensis, to which, according to the observations of Prof. 

 Heer, this new species is closely allied, the veinlets are variable in number. 

 Though I consider our species as identical with that of Alaska, I do not assert 

 that it represents a Phragmites. If the leaf in fig. 10 is rightly placed, and 

 is obtusely mucronate, this same character, though somewhat less marked, 

 is seen in leaves of Phragmites CEningensis, as figured by Heer (Fl.Tert. Helv., 

 pi. cxlvi, fig. 22); if, per contra, the specimen is overturned, and if that mucro- 

 nate part represent the base narrowed to the point of attachment, this would 

 force the separation of these leaves from the genus Phragmites, and indicate 

 their reference perhaps to Bambusia. But it is possible that we have here two 

 species, as that in fig. 12, which more positively agrees with Heer's description 

 and figures of P. Alaskana, is from a specimen of a different locality from those 

 of figs. 10 and 11, the only ones where the secondary nervation could be dis- 

 cerned by abrasion of the epidermis. These, therefore, might be referable 

 to Bainbusia, and that in fig. 12 identical with the species from Alaska. The 

 relation of the specimens in figs. 10 and 11 is remarkably close to Phragmites 

 Cretaceus, Lesqx., as described in Cret. Fl., p. 55, pi. xxix, fig. 7. 



Habitat. — Green River group, specimen of fig. 12, in connection with 

 numerous leaves of Ficus; the others six miles above Spring Canon (Dr. F. 

 V. Hay den). 



