CHAPTER I. 



DESCRIPTION OF THE SOUTHERN PORTION OF THE PLAINS PROVINCE. 



THE TEXAS REGION. 



LOCATION OP THE BEDS.* 



The region most prolific in vertebrate fossils of Pernio- Carboniferous 

 age lies in north-central Texas, mostly in Wichita, Archer, Wilbarger, and 

 Baylor Counties, but the relatively abundant finds of fossils in this area are, 

 in part at least, due to the fortunate exposure of large areas of "bad lands" 

 devoid of vegetation and dissected by erosion. The same beds extend over 

 a much larger area, being exposed far to the south in Texas and to the north 

 in Oklahoma, with evidence that they extend north even to the Black Hills 

 and west to the Rocky Mountains. Gould has given the following outline 

 of the portion of the beds which have yielded vertebrate remains:'' 



"The most northern exposure of the beds, so far as known to the writer, is 

 near Arlington, a few miles south of Hutchinson, Reno County, Kansas. The 

 eastern border of the outcrop of the Red Beds in Kansas and Oklahoma is a crescent- 

 shaped line running southeast from near Hutchinson and east of Kingman, Kansas, 

 crossing the Kansas-Oklahoma line at Caldwell, then trending southeast near 

 Nardin, Tonkawa, and Red Rock, cutting diagonally across the strike of the 

 Pennsylvanian limestones and shale through the eastern part of Payne and Lincoln 

 Counties to the western part of the Creek and Seminole Nations. Here the line 

 swings to the southwest, and continues through the Chickasaw Nation to the 

 vicinity of Davis, Indian Territory, passes around the western end of the Arbuckle 

 Mountains, crossing Red River 35 miles west of Gainesville, Texas, and, as stated 

 by Adams, cuts diagonally across the strike of the Pennsylvanian limestones in 

 Archer, Young, and Throckmorton Counties, Texas." 



Beyond Throckmorton County the Red Beds reckoned as Permo- 

 Carboniferous may be traced, as described by Cummins, generally south- 

 west through western Shackelford County and eastern Jones County, fol- 

 lowing the course of the Clear Fork of the Brazos River, thence south in 

 extreme western Callahan County to near its middle line ; thence southwest 

 across the southeast corner of Taylor County, and then generally south 

 through central Runnels County or a little east and south through Concho 

 County to beyond the Concho River. Here the line turns west beneath 

 the outcrop of the Cretaceous to the edge of the Llano Estacado, which it 

 follows north to the latitude of Amarillo; north of Amarillo it appears in the 

 breaks of the Canadian near Plemons, in Hutchinson County, and possibly 



» Compare map opposite page 6, plate i . 



•> Gould, U. S. Geological Survey, Water Supply and Irrigation Paper No. 148, p. 37. 



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