Illustrations
[Figure 1. Geologic Map of Palo Duro Canyon] 6 [Figure 2. Stratigraphic Section and Geologic Time Scale] 7 [Figure 3. Paleogeographic Map of the Permian Period] 9 [Figure 4. Paleogeographic Map of the Triassic Period] 11 [Figure 5. Paleogeographic Map of the Pliocene Epoch] 13 [Figure 6. Paleogeographic Map of the Pleistocene Epoch] 15 [Figure 7. Life of Triassic Time] 17 [Figure 8. Pliocene Mammals] 19