pt. 1. The Eocene fauna / Loris S. Russell -- pt. 2. The Oligocene fauna, non-ungulate orders / Loris S. Russell -- pt. 3. The Miocene fauna / John E. Storer -- pt. 4. The Oligocene anthracotheres / Loris S. Russell -- pt. 5. The Oligocene entelodonts / Loris S. Russell -- pt. 6. The Oligocene rhinoceroses / Loris S. Russell -- pt. 7. Oligocene marsupials / Loris S. Russell