DESCRIPTION OF SPECIES— PALMiE. 117 



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

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

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

 rarely, after 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 be 

 compared. Flabellaria 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). 



Oeouomites ten ni rachis, sp. nov. 



Plato XI, Fig. 1. 



Flabellaria longirachis?, Uug., Lesqx., Aunual Report, IS/S, p. 396. 



Froud elongated, apparently linear in outline ; rachis very narrow, grooved in the middle; rays 

 joining the rachis by a decurrent base, obtusely carinate ; nervation obsolete. 



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

 sent the upper part of a long, 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. (J.oc. cit.), 

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

 with the obsolete nervation. But in lingers two figures, which, fine as they 

 are, show more than is remarked in the description, the 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 both Unger's speci- 

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



