Chapter III—The Paleozoic Era 9

First Animal Life—The Tonto Rocks 9 The Missing Periods of the Third Era 11 The Age of Fish 12 Sea Life From the North—Redwall Limestone 12 Tracks in the Supai Sandstone 14 Landscapes of the Hermit Shale 15 Wind-blown Sand—The Coconino Sandstone 17 Warm Seas from the West—The Toroweap and Kaibab Formations 18