A Acknowledgments, 130 Agate, 53 Airport, Walker Field, 85 Albuquerque, N. Mex., 16 Algae, 27, 47 _Allosaurus_, 4, 50, _52_, 60 Anasazi people, 129 Animals, buffalo, _3_, 91, 94, 105 cattle, 101 deer, 2 elk, 2, 109 sheep, 99 Anthropoid primates, 76 Anticlines, 61, _62_ _Apatosaurus_, 50, _52_ _excelcus_, 96 Archaeological survey, 1963, 8 Archean Eon, 24, 125 Arches, _61_ Arches National Park, XI, 36, 129 Area, Colorado National Monument, 5 Artesian wells, 14 Artifacts, Indian, 5, 8 Artificial fill, view, _98_ Artists Point, 45, 105 view, _46_