108 UNITED STATES GEOLOGICAL SURVEY— TERTIARY FLORA. 



cral subdivisions of this family, and are accordingly distributed to the following 

 genera : — 



1. Flabellaria, Sternb., modified in the generic characters, and limited to 

 Palm leaves or fronds whose rays are all attached to the top (either rounded, 

 or truncate, or obtusely angular) of the rachis. This generic name has been 

 employed, when referred to Palms only, for all the fossil species of this 

 family whose relation is not well ascertained. But it seems an anomaly to 

 describe in the same generic division species of Palms with flabellate leaves 

 and acutely carinate rays, all attached to the top of an obtuse rachis, and 

 others with either flabellate or pinnate fronds whose divisions are fixed along 

 a generally narrow and very long rachis. 



2. Sabalites. Fronds with rachis broad, often enlarged at the top, 

 gradually narrowed up to a long acumen, bearing deeply cariuato-costate rays 

 attached along it, and flabellate, like Sahal. 



3. Geonomites. Fronds with a long and comparatively narrow rachis, 

 simple at first, but soon pinnately divided, or laciniate, with rays carinate 

 er half-cylindrical toward the base, joining the rachis by their whole base, 

 sometimes half-sheathing. 



In describing Flahellaria longirachis, Ung., Schimper remarks, in Pal. 

 V^g^t., ii, p. 492, that it evidently constitutes the type of a peculiar genus, 

 which, by its characters, the length of the rachis, etc., seems intermediate 

 between the Palms with flabellate and those witli jjinnate fronds. Count 

 Saporta writes the same in regard to the species here referred to this genus, 

 and believes, according to his remarks in S(jzanne Flora, p. 339, that they con- 

 stitute a distinct group, having some analogy with the Geo7ioma oi^ the present 

 time. This genus, according to Willdenow, who established it, is distributed 

 by a number of species in tropical America, between 20° latitude north and 

 10° latitude south. Its characters have some analogy with those of (he fossil 

 species of this division by the fronds, at least, which at first, simple and 

 flabellate, soon divide in irregular pinnae, and become laciniate, the rays 

 sometimes half-sheathing, etc. 



With the fragments of Palm leaves, and in the same strata, numerous 

 hard fruits have been found in the Lower Lignitic. They are especially 

 common at Golden. As they bear (he. characters of fruits of Palm, it seems 

 advisable to describe them separately under a more appropriate name than that 

 of Carpolithes. The name of Pahnocarpon is therefore used here for the clas- 



