INDEX. 



341 



Tucson, climate of, 9, 10 

 floods at, 33 

 Mountains, 18, 34, 54 

 region, terraces of, 24 

 ruins at, 51 

 terraces at 33 S. 

 Tulare River, 142 



Sequoias at, 144 

 Tularosa gypsum, 42 



terraces of, 26 



Valley, relation of terraces to man, 44 f. 

 Tulip poplar, conditions favorable to growth, 132 

 corrective factor of, 132 

 curve of growth, 133 

 Tultitlan, inundation of, 97 

 "Tun" in Maya chronology, 227 

 Timnel, for drainage of Mexican Lakes, 97, 209 

 Tuxtla statuette, 228 

 Tyuyoni, ruins, 83 



United Fruit Co., 216 f. 

 Upper Carbonic: 



Coal-making in, 28(5 



Mountain-making in, 278 

 Upper Cretacic, coal-raaking in, 286 

 United States Forest Service, 3 

 Urals, rise of, 278, 287 

 Utah, comparison with Arizona, 21 

 Uxmal, ruins of, 229 



Valladolid, rainfall of, 178 

 Variations in rate of tree growth, 123 ff. 

 Vegetation, causes of variation in rate of growth. 157 

 in relation to old Otero Lake strands, 39 f. 



Yucatan, 178 f. 

 of Guatemala, relation to climatic changes, 

 212 

 monsoon desert, 21 f. 

 mountains of Arizona, 18 

 Rio Grande Valley, 83 

 rapidity of growth in Tropics, 181 

 relation to terraces, 31 ff. 

 Velasco, Luis de, 97 

 Verde River, terraces and ancient irrigation, 44 



VaUey, 102 

 Volcanic activity, relation to geological climate, 261 



dust in atmosphere, effect on temperature, 250 ft 



as climatic factor, 274, 286, 287 

 phenomena in Guatemala, 211-212 

 Volcanism, and critical periods, 287 



mountain-making, 286 

 Devonic, 287 

 Eocene, 283, 287 

 Liassic, 280 

 Siluric, 287 

 Volcanoes, effect on climate, 250 ff. 



relation to lakes in Guatemala, 211 



Wakefield, W. J., 57 



Walls for defense, at Charco Yuma (see also Forts) , 56 



Ward, L F., cited, 91 



Ward Line of steamers, 176 



Warping of earth's crust in relation to terraces, 28 ff. 



Wars, relation to changes of climate, 88 



Water Canyon, 72 



Water for drinking (see Drinking water). 



Water-supply (see Drinking water; Agriculture; Floods; 



Drought)," of Yucatan, 184 

 Wealden formation, 282 

 Weapons of Hohokam, 68 

 "Weather cycles in the growth of big trees," 101 



Weatherell, Mrs., cited, 81 

 Wells, depth of, at Nelson's Ranch, 57 

 effect upon Indians, 51 

 in Yucatan, 177, 184 

 WTieat prices in England compared with Sun-spots, 239 f . 

 Whipple Barracks, Ariz., 103 

 White fir, habitat of, 141 



oaks, conditions favorable to growth, 134 

 corrective factors of, 132 

 cvu-\'e of growth, 133 

 distribution of, 134 

 sands of Otero Basin, 40 ff. 

 Wild animals, relation to Hohokam, 79 

 WiUis, B., cited, 23 

 Willis and Blackwelder, on tillites of China 269, 271, 272, 



293, 294 

 Windmills in Yucatan, 177 

 Winds, effect on civilization, 219 

 Wolf, cited, 238 



Women, occupations among Hohokam, 69 

 Wood, use of among Hohokam, 77 



with rings, Upper Cretacic, 282 

 Wright, J. B., cited, 58 



Xochimilco Lake, 95 



Yaxchilan ruins, 229 



YeUow fever, 220 



Yellow pine, 101 ff. (See Pines.) 



Corrective factors of, 129 ff. 



Curve of growth, 133 



In New Mexico, 128 



Of New Mexico, distribution of, 128, 134 



Opposed phases of growth in Idaho and New Mexico, 

 136 

 Yellowstone River, terraces of, 26 

 Yucatan: 



Causes of present depopulation, 189 f. 



Changes of chmate in, 189 ff. 



Civilization of, 182 ff. 



Chmate of, 177 f. 



Coasts of, 176 



Distribution of population in, 180 



Drainage of, 177 



Effect of climatic changes upon seasonal precipitation, 

 206 ff. 

 cool weather in, 210 



Former storminess of, 206 



Inhabitants of, 179 ff. 



Isolation of, 176 



Peninsula of, 175 ff. 



Present civilization of, 182 



vs. past population, 183 



RainfaU of, 177 



Relation of precipitation to "northers," 206 



Topography of, 176 f. 



Water-supply of, 177, 184 



Vegetation of, 178 f. 

 Yuma, cUmate of, 9, 10 

 rainfall, 21 



Zacapa, terraces at, 213 



vegetation of, 217 

 Zapote tree, use for beams, 



gum, 186 

 Zon, R., cited, 132 

 Zuni Indians, 75 



Relation to Hohokam, 

 Moimtains, 76 

 National Forest, 128 



183 



48 



