AN EOCENE ELOKA FROM TKANS-PECOS TEXAS. 



Leaves of fan palms are the most abundant 

 fossils in the basal tuffs of the Barilla Moun- 

 tains. The material is fragmentary, and as it 

 represents both large and small leaves more 

 than one species may be represented. It has 

 seemed best, however, to consider all the speci- 

 mens collected as representing different^sized 

 leaves of a siagle species, as no differential 

 characters other than those of size can be 

 distinguished. 



It is with considerable hesitation that I 

 identify these remains as belonging to this 

 species, and possibly instead of representing 

 Sabalites grayanus they should be referred to 

 Sahal ungeri (Lesquereux) Knowlton, which is 

 exceedingly common in the Raton formation 

 of Colorado and New Mexico and possibly 

 occurs elsewhere in the Eocene of the western 

 United States. There is also the further 

 possibUity, alluded to by Knowlton, that the 

 two may represent a single species, and in any 

 event the convergence of characters is marked 

 and they are at least closely related. The 

 following description of Sahalites grayanus is 

 quoted from my account of the Wilcox occur- 

 rence : 



Leaves of large size but mostly fragmentary. Petiole 

 long and stout, unarmed, enlarged at the base of the leaf, 

 and tapering into an extended and gi'adually narrowed 

 acumen, which is not visible on the upper surface of the 

 leaf, where the petiole is broadly rounded and a short 

 and inconspicuous ligule is developed. From the manner 

 of preservation and attitude of the rays on some of the 

 specimens it is inferred that the acumen was recm-ved, as 

 it is in the existing Sahal palmetto (Walter) Roemer and 

 Schultes. Rays very numerous, about 100 in number, a few 

 reduced basal ones on each side free, the remainder united 

 for a variable distance above the base. Their dimensions 

 and the relative thickness of the venation are variable 

 features dependent on the size of the leaves. The largest 

 specimens seen have thick carinate stout-veined rays, 5 

 centimeters in maximum width. They increase in size 

 from the base of the leaf upward, and individually they are 

 narrow at their point of attachment, widening medially 

 and becoming gradually narrowed into long acuminate 

 tips. Venation characters variable, largely dependent on 

 the size of the leaves and the condition of preservation 

 of the epidermis in the fossil specimens. In well-pre- 

 served material there are four of five relatively thin inter- 

 mediate veins. Between each pair of veins there are six 

 to eight fine veinlets, which are not visible except in 

 well-preserved specimens. 



Sahalites grayanus is a somewhat protean 

 species which was described by Lesquereux 

 from the WUcox clays (" Eolignitio ") of Lafay- 

 ette County, Miss. None of Lesquereux's 



type material appears to be extant at the 

 present time, but it seems probable that it 

 came from a locality near Oxford. Within 

 the next ten years after the publication of his 

 original description of this species Lesquereiix 

 identified it from a large number of localities 

 in Colorado, Wyoming, and Vancouver Island. 

 Nearly all of this material is now in the United 

 States National Museum and in my judgment 

 does not represent this species. Eoiowlton ^ 

 has recorded five species of Sahal-like palms 

 from the Raton formation of southeastern 

 Colorado and northeastern New Mexico. Palm 

 leaves are the most abundant fossils in that 

 formation, and the wealth of this somewhat 

 intractable material (so far as generic and 

 specific differentiation is concerned) affords 

 abundant testimony regarding the climatic 

 conditions and the abundance and variety of 

 the palms in the early Eocene history of the 

 Rocky Mountain region. 



Genus GEONOMITES Visiani. 



Geonomites visianii Berry, n. sp. 



Plate II. 



Leaves of medium size, ovate in general out- 

 line, becoming cleft distad at maturity. Length 

 (estimated) about 75 centimeters; maxiraum 

 width (estimated) about 40 centimeters. 

 Rachis very stout, as much as 1 centimeter in 

 diameter in the preserved material, very prom- 

 inent on the under surface of the leaf, where it 

 is semicircular in section, not keeled; flat or 

 channeled on the upper surface. Laminae in- 

 serted on the lateral margins of the upper sur- 

 face of the rachis, consisting of 75 to 100 un- 

 differentiated rays on each side, which are 

 united for all or a greater part of the distance 

 to the margin. The rays are but shghtly if at 

 aU plaited and do not contract proximad. 

 They diverge from the rachis at angles averag- 

 ing about 30° and curve upward shghtly and 

 regularly as they proceed toward the margin. 

 They are 6 to 8 millimeters in width, with a 

 thin principal vein, and 10 to 12 thin parallel 

 veins on either side of the principal vein. (See 

 fig. 1.) 



The texture of these leaves appears to have 

 been coriaceous, for although their substance 

 has mostly disappeared during f ossihzation they 



'Knowlton, F. H., U. S. Geol. Survey Prot. Paper 101, pp. 288-291, 

 1918. 



