CARBONIFEROUS. 375 



stones, as well as clays and sandy shales. In it occurs Coal Seam No. 7. 

 This is the most extensive and continuous division in the entire series. It 

 begins at the most northern extension of the Northern area and continues to 

 the most southern extremity of the Central area. There is only one small 

 area where it is covered by the overlying Cretaceous, and that is a few miles 

 south of the line of the Texas and Pacific Railway, opposite to the town of 

 Putnam, in Callahan County. This division usually extends to the western 

 border of the "Upper Cross Timbers," and in the Central area it extends be- 

 yond their western border. The conglomerates in this division very much 

 resemble the conglomerates found in the Strawn division, and were supposed 

 by Mr. Ashburner to be the same beds, and were by him put in the Sub-Car- 

 boniferous and made equivalent with the millstone grit. The sandstones are 

 much the same as those in the Strawn division but are harder. This division 

 can best be determined by its stratigraphic position — below it is always found 

 the heavy beds of limestone of the Canyon division. 



Albany Division. — This is the upper division of the Carboniferous series 

 in Texas. It is named Albany division for the reason that in the vicinity of 

 Albany, in Shackelford County, the strata are well developed. The strata of 

 this division are largely composed of limestone and shales, there being very 

 little sandstone except at the base of the division. The division does not oc- 

 cur in the area north of the Brazos River, but is continuous as far south as 

 the southern extremity of the Southern area. It is overlaid along the entire 

 western border by the Clear Fork Beds of the Permian. This division is all 

 west of the western boundary of the "Upper Cross Timbers." A small area 

 only is overlaid by the Cretaceous, and that occurs a few miles south of the 

 town of Baird, in Callahan County. 



This division embraces all the strata above the sandstones of the Cisco di- 

 vision to the base of the Permian. The boundary between the Permian and 

 Carboniferous is determined largely upon paleontologic grounds, and will be 

 discussed more at length in another place in this Report. The limestones of 

 this division are generally in thin beds, but in places they are massive, being 

 four or five feet thick. 



SECTION NO. 2. (PLATE XVI.) 



This section was made from San Saba River, near the town of San Saba, 

 to Brownwood, and thence to the head of Pecan Bayou, in the western edge 

 of Callahan County. 



a. San Saba River. 



b. Colorado Civer. 



c. East Comanche Creek. 



d. Middle Comanche Creek. 



e. West Comanche Creek. 



