PERMIAN. 401 



stones in it from bottom to top. The sandstones are of various colors. The 

 clays are red and bluish. In places the clay is copper bearing, yet this is not 

 entirely peculiar to these beds, as the same thing occurs in the Clear Fork 

 Beds. In the red clays are iron concretions that exist in places in great 

 abundance. The peculiar Permian conglomerate which is found in this con- 

 nection is composed of clay, or clay ironstone, in a ferruginous matrix. 



The fossils occurring in these beds will be mentioned in another place in 

 this Report. 



The boundary between the Wichita Beds and Clear Fork Beds begins at a 

 point on the Brazos River a little west of the mouth of Mule Creek, near the 

 southeast corner of Baylor County, and extends by a direct line nearly north 

 to Red River. The southeastern border would be the line between the Coal 

 Measures and the Permian as given in another place. The Wichita Beds do 

 not extend south of the Brazos River. These beds are heaviest along the 

 Big Wichita River, where they attain a thickness of about two thousand feet. 



The Albany Beds of the Coal Measures not occurring north of the Brazos 

 River, the Wichita Beds rest directly upon and are conformable with the 

 Cisco Beds. At first glance in passing over the country one would conclude 

 that there had been a continuous sedimentation between these two beds, but 

 upon closer inspection, and by taking a wider view, it is seen at once that 

 this is not true. The Albany Beds of the Coal Measures are, at the point 

 where we measured them, one thousand one hundred and twenty-five feet 

 thick, and the whole of this division is lacking between the Cisco Beds of the 

 Coal Measures and the Wichita Beds of the Permian. 



CLEAR FORK BEDS. 



The Clear Fork Beds is the name given to the middle division of the Per- 

 mian strata, and they lie immediately west of the Wichita Beds for their en- 

 tire length, and are then found resting upon the Albany Beds of the Coal 

 Measures for the balance of their extent to the southward. 



These Clear Fork Beds are composed of limestones, clay and shale beds, 

 and sandstones. 



The limestones are mostly magnesian and carbonaceous, some of them be- 

 ing so largely impregnated with carbonaceous matter that when struck with a 

 hammer they give off a peculiar odor, which has given such stones the name of 

 "stmkstone." These limestones carry an abundant and characteristic fauna. 



The sandstones are not so abundant as in the Wichita Beds, and are not so 

 massive, but are generally thin bedded. 



The clays are blue and red, the red occurring in thick, heavy beds. The 

 blue clays are in places copper bearing. The conglomerate is similar to that 

 found in the Wichita Beds, but is not so abundant and is less compact. 



