474 



G. B. Richardson — Paleozoic Formations. 



Aet. XLIX. — Paleozoic Formations in Trans-Pecos Texas ; 

 by G. B. Richardson.* 



The presence of Paleozoic rocks in trans-Pecos Texas has 

 been known since the middle of the last century, when fossils 

 were collected by the surveying' parties engaged in exploring 

 routes for a Pacific railway and in establishing the boundary 

 between the United States and Mexico. f In 1874 W. P. 

 JenneyJ measured a section of the rocks in the Franklin 

 Mountains, north of El Paso, and called attention to the long 

 Paleozoic sequence there exposed, which in 1896 was also 

 examined by C. D. Walcott. W. H. von Streeruwitz and E. T. 

 Dumble made a number of references to the Paleozoic rocks 



in the vicinity of Van Horn, in the reports of the Geological 

 Survey of Texas, 1890-93, but that organization was discon- 

 tinued before correlations and maps were published. 



An important result of the early surveys was the determina- 

 tion by the Shumard brothers! of the presence of a Permian 



* Published by permission of the Director of the U. S. Geological Survey. 



f Explorations and surveys for a railroad route from the Mississippi Eiver 

 to the Pacific Ocean, vol. ii, Washington, 1855. Eeport of the United 

 States and Mexican Boundary Survey, by Wm. H. Emory, vol. i,. part 2, 

 Washington, 1857. 



JThis Journal (3), vii, p. 25, 1874. 



^Transactions St. Louis Academy of Science, vols, i and ii, I860, 1868. 



