19

• Page.
• PLATE I. Natural provinces of the Texas region . . . 26
• II. A, Hypsometric map of Texas region; B, Geologic map of Texas region . . . 30
• III. 11, A summit of the Llano Estacado; B, Breaks of the Llano Estacado . . . 44
• IV. Signal Park, a summit of the Callahan Divide, Mitchell County, Texas . . . 46
• V. A mountain in the Trans-Pecos district . . . 48
• VI. A and B, Desert plains, Trans-Pecos Texas . . . 50
• VII. Drainage of the Texas region . . . 52
• VIII. Colorado River, looking west from Mount Bonnel, Texas . . . 54
• IX. Fissure spring, Barton Creek, Austin, Texas . . . 56
• X. The Black and Grand prairies and Eastern Cross Timbers of Texas and Indian Territory . . . 60
• XI. Drainage of the Black and Grand prairies . . . 64
• XII. Scarps of the Lampasas Cut Plain, Burnet County, Texas . . . 78
• XIII. Summits of the Lampasas Cut Plain, Lampasas County . . . 80
• XIV. View of the Burnet district, showing the margin of the Edwards Plateau in the distance . . . 88
• XV. Variation in thickness of the Cretaceous formations in the Texas region . . . 108
• XVI. Formation symbols . . . 110
• XVII. An outcrop of the Del Rio clays, Shoal Creek, Austin, Texas, showing Exogyra arietina . . . 116
• XVIII. Red River section of the Cretaceous formations, Grayson County, Texas . . . 118
• XIX. The Cretaceous formations in the Dallas-Weatherford section . . . 120
• XX. Columnar sections of the Cretaceous formations, Travis County, Texas . . . 126
• XXI. Characteristic fossils of the Travis Park and Glen Rose formations . . . 144
• XXII. Glen Rose formation, bluffs of Mount Bonnel, west of Austin, Texas . . . 146
• XXIII. Butte of the Glen Rose formation, Travis County, Texas . . . 148
• XXIV. Fossil fish from the base of the Glen Rose beds, Glen Rose, Texas . . . 160
• XXV. Characteristic fossils of the Glen Rose beds, Texas . . . 162
• XXVI. Fossil plants from the base of the Glen Rose formation, Glen Rose, Texas . . . 164
• XXVII. Characteristic fossils of the Walnut clays and Comanche Peak limestone . . . 226
• XXVIII. Edwards limestone, Barton Creek, Texas . . . 228
• XXIX. Quarry in the Edwards limestone west of Austin, Texas . . . 230
• XXX. Flint from the Edwards limestone . . . 232
• XXXI. Flints in the Edwards limestone, bluff of the Colorado, Austin, Texas . . . 234
• XXXII. Weathered Edwards limestone with characteristic fossils, Austin, Texas . . . 236
• XXXIII. Characteristic fossils of the Edwards limestone . . . 238