The following pages, descriptive of the results of a trip across Central Texas and into the Gaudalupe mountains, which lie some seventy five miles west of the Pecos river stretching northwest and southeast across the line between Texas and New Mexico, were intended for publication in the Second Annual Report of this Survey. On account of the number and length of the papers on hand it was necessary to omit several which will be issued as Bulletins.

The work assigned Mr. Tarr contemplated a much more detailed investigation than is here recorded, but circumstances prevented its completion. His return to Cambridge and consequent separation from the materials he had collected on the trip has prevented anything like a complete study of them, and it must be considered, therefore, that the opinions expressed are, as Mr. Tarr says, tentative only, being simply the ideas formed during the field study which, while it was done as carefully as possible, was necessarily of a somewhat rapid character. The facts observed, however, are of considerable interest and add their quota to our knowledge of the topography and geology of this hitherto little known region.

During the present summer further explorations have been made of this range by Prof. Cummins who followed down it from the north. The results of this will be found in his paper in the Second Report of Progress, now in press, and in greater detail in the Third Annual Report. of the Survey.

E. T. DUMBLE,
State Geologist.