134 PROCEEDINGS OF THE ACADEMY OF [1895. 



deposits overlying. Wide "bottoms" and "second bottoms" laud 

 fringe the margins of the main streams and many of the larger 

 creeks, and the whole flow at very low levels, often one hundred to 

 one hundred and fifty feet below the summit making deep V-shaped 

 channels where no bottom lands exist. In many places, particularly 

 in the sandy beds erosion is very rapid and many of the eastern 

 water courses have reached and are now flowing in the underlying 

 lignitic beds. 



Throughout the higher grounds the surface is generally covered 

 with light gray or yellow sand derived from the disintegration of the 

 underlying beds through leaching or otherwise, and in places a light 

 scattering deposit of yellow stained quartz gravel occurs. These 

 upper beds support a heavy cover of short leaved pine, oak and hickory 

 in portions of the region and wide areas in several of the counties 

 towards the middle of the district are covered with heavy beds of 

 laminated iron ore. These overlying sands and ores have been 

 ascribed to the quaternary by Mr. L. C. Johnson," but the occur- 

 rence of fossils of the same age as the underlying beds within them 

 place them in the Marine beds and consequently of Eocene age. 



Lignitic Beds. 



The northern boundary of the Marine beds marks the southern 

 limit of an another series of deposits totally differing from these in 

 every respect. In physical structure, materials and mode of deposi- 

 tion these lower beds have nothing in common with the overlying 

 Marine beds. They form the lowest portion of Penrose's Timber 

 Belt or Sabine river beds and are known as the Lignitic stage of 

 the Texas Eocene. These beds comprise a series of sands, clays and 

 lignites and have an aggregate thickness of over 1,200 feet. 



The sands are variously colored, being white, yellow, brown, red, 

 gray or blue, with occasional thin beds of black, often shading 

 into one another in endless variety, and, with the exception of the 

 dark blue or black and occasionally white beds, present no uniform- 

 ity of coloration for any distance. In structure they are mostly 

 coarse-grained with irregular deposits of fine-grained silty sand, 

 laminated or thinly stratified, massive, cross-bedded and frequently 

 interlaminated with clay. 



The clays occur interstratified and interlaminated, or as irregular 



60 Iron Ores of East Texas and Northern Louisiana, L. C. Johnson, p. 25. 



