DESCEirXION OF srEClES— PALMiE. 117 



a little above the racbis. Marked in tbc middle by a deep midrib, and thus 

 subcarinate, they show on both sides of it ten to fourteen inflatcul primary 

 veins, witli few intermediate veinlets, two to four discernible only, and even 

 rarely, atler abrasion of the epidermis. The substance of the fronds is 

 thin, membranaceous, of a dull red color, a character which may be casual. 



I do not know of any fossil species of Palms to which this one may l)e 

 compared. Flahellaria longirachis, Ung. (Iconog., p. 19, pi. viii, ix, fig. 1), 

 has a very long and narrow rachis, but its smooth surface, as well as the 

 characters of the palmate rays, are far different. 



Habitat. — Divide between sources of Snake River and the southern 



shores of Yellowstone Lake, with Gymnogramma Haydenii {Dr. F. V. 



Hayden). 



Geouomitcs tcuuiracliis, sp. nov. 



Plato XI, Fig. 1. 



Flahellaria loiirjirachuf, Dug., Lesqx., Annual Report, 1873, p. 396. 



Frond elongated, apparently linear in outliuo ; rachis very narrow, grooved in the middle ; rays 

 joining the racbis by a decurreut base, obtusely carinate; nervation obsolete. 



The only specimen seen of tliis species is figured. It appears to repre- 

 sent the upper part of along, linear-lanceolate frond, palmato-pinnate, with a 

 very narrow rachis, to which the rays are attached in an acute angle of 

 divergence, scarcely 20°. The rachis is about two millimeters thick, smooth, 

 and grooved in the middle. The rays, obtusely carinate, narrow, about one 

 centimeter wide, including both faces, become flat and slightly decurrent 

 toward the rachis, curve inward in narrowing, and seem to become free or 

 cut from each other toward their points. The substance is thick and coarse, 

 the nervation nearly totally obsolete, except where the rays, destroyed by 

 maceration, have left indistinct traces of nerves, as marked upon the right 

 side of the figure. 



I referred, with doubt, this form to Flabellaria longirachis, Ung. {loc. ci(.), 

 from the size of the rays, their obtusely carinate and rough surface, together 

 with the obsolete nervation. But in Unger's two figures, whicli, fine as tliey 

 arc, show more than is remarked in the description, tlie rachis is of a differ- 

 ent character, the rays being half-cylindrical, very long and linear, connected 

 in their whole length. Our too small specimens may, however, be the point 

 of a long frond, whose base would be represented by l)oth Unger's si>eci- 

 mens. In this case, however, as in otiiers, where identity with European 



