526 F. II Knowlton — Study of the Coal-hearing Bocks 



Art. XLIY. — Results of a P aleobotanical Study of the Coal- 

 bearing Rocks of the Raton Mesa Region of Colorado and 

 New Mexico :*■ by F. H. Knowlton. 



The Raton Mesa region comprises an area about 90 miles 

 long by 50 miles wide, lying along the east front of the Rocky 

 Mountains and extending from near Walsenburg, Colorado, on 

 the north, to the Cimarron River, New Mexico, on the south. 

 The coal beds within this area are numerous and extensive and 

 have long been mined and exploited. The object of the pres- 

 ent paper is to show the pronouncement of the fossil flora on 

 the question of the age of the coal-bearing formations involved. 



Although the presence of coal in this region had long been 

 known, the first to bring back any paleobotanical evidence 

 bearing on its stratigraphic position apparently was Lt. T. W. 

 Abert, who visited New Mexico under conditions of the great- 

 est hardship in the winter of 1846. The coal was presumed 

 to be similar to that of the Missouri region — namely, Carbon- 

 iferous — but the finding of modern-appearing dicotyledonous 

 leaves both above and below it showed of course that it was 

 very much younger, though no attempt was then made to fix 

 its position more exactly. 



The first plants from the region to pass under scientific eyes 

 were obtained in July, 1867, by Dr. John L. LeConte while serv- 

 ing as geologist on one of the Pacific Railroad surveys. These 

 plants came from beds now know to be in the upper part of 

 the section. They were studied by Lesquereux, who pronounced 

 them to be of Tertiary age. LeConte, however, considered the 

 beds as Cretaceous in age from the presence of certain marine 

 invertebrates, though these were not found in place. 



In 1869 a considerable collection of plants was secured from 

 the Fisher's Peak region by Dr. F. Y. Hayden, and his account 

 of their occurrence, together with a description of the general 

 geology of the region, is presented in his Third Annual Report. 

 These plants also were studied by Lesquereux, who referred 

 them to the Eocene and at the same time pointed out their un- 

 doubted affinity with Lower Tertiary (Eolignitic) flora of Mis- 

 sissippi, f In 1872 Lesquereux himself visited the region and 

 added a few species, among them being apparently the first to 

 be obtained from the lower coal-bearing rocks, now known as 

 the Trinidad sandstone. In 1878 Lesquereux published his 

 Tertiary Flora,% in which he brought together all the scat- 



* Published with the permission of the Director of the U. S. Geological 

 Survey, 

 f 5th Ann. Kept. U. S. Geol. & Geogr. Serv. Terr., 1872, Sup pi., p. 19. 

 % Kept. U. S. Geol. Surv. Terr., vol. v, pp. 1-366, pis. i-lxv, 1878. 



