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Coleman beds in other sections, the bluffs being on the outcrop (S. E.) side, and the chief erosion being that of the soft clays and the consequent breaking down of the harder limestone layers. This process has entirely obscured thick and numerous beds of clay where other evidence has proved their existence. Furthermore much of the exposed Carboniferous has not suffered extensive denudation, since it has been only recently uncovered.

The fossils of these beds are not varied in the number of forms, but some beds contain a great abundance of individuals belonging to such groups as Pinna, Myalina, Bellerophon, and certain Bryozoans. Everything indicates that fossils fitted for hardy life were the only ones to flourish under the conditions that then existed. A specimen of Pleurophorus, found just northwest of Coleman, points to the approach of Permian times.

Just northwest of the fork of Jim Ned creek the approaching change from Carboniferous to Permian previously indicated by the change in fauna receives further confirmation by a lithologic change. The dip of the strata, however, appears to remain unchanged. No unconformity or overlap appears in this line of section, and if such phenomena exist, they can be detected only by continued work along the line of contact. One would infer from all the evidence that appears in the single section traversed that the red beds of Central Texas directly and conformably succeeded the Carboniferous with a line of contact that must be arbitrarily drawn. Certainly, however, the Permian is foreshadowed in the Carboniferous and in the Permian, relics of the Carboniferous are found, so that the break, if any existed, was small indeed.

The Permian in its best development is in nearly every way distinct from the the typical Carboniferous and in many ways from the upper beds of the Carboniferous. There is only a tract of a few miles in breadth about which any doubt can be entertained. The beginning of the Permian epoch was indicated in Central Texas at the close of the deposition of the beds of the Brownwood division. The seashore deposits of the Waldrip division with its accompanying bed of coal apparently marked the beginning of the great inland sea which reached its best development in Permian times. Throughout much of the Coleman strata seashore deposits reappear at frequent intervals as the section is studied upward and everywhere the presence of an abundance of clay is indicated. The faunal features still remain Carboniferous throughout the Coleman beds, but the life is in many ways different from that which existed during the deposition of the Brownwood beds in the clear deep water.

The apparent transition stage between Carboniferous and Permian