307 



Summer-deciduous trees and shrubs, 

 77-79 



Sundew, 53*, 54 



Sunflower stem, cross section of, 62*, 

 63 



Superior ovary, 132 



Suspensor cells, 303* 



Swamp lands, 321 



Sweet potato, sprouting of, 32* 



Switch plants, 56*, 57 



Sycamore fruits, 108* 



Sycamore log, 111* 



Symbiotic saprophytes, 52 



Symmetry, 129 



Sympetalous, 128 



Synergids, 300, 301* 



Synsepalous, 128 



Syringa (Philadclphus) leaves, ar- 

 rangement of, 71* 



Systematic botany, 197 



Taxodium, 26* 



Taxonomy, definition of, 197 



Teleutospores, 254, 255* 



Temperature and germination, 161 



Tendril, 75*, 76* 



Tendril climbers, 74*, 75*, 76* 



Terminal bud, 95* 



Testa, 158* 



Thallophytes,classificationof,260,261 



Thallophytes, in relation to evolution 



of plants. 305 



Thickening of stems, 12*, 66, 67 

 Thistle, Russian, 167, 168 

 Thorn tree, bud section of, 100* 

 Thuja, 293*, 294 

 Tillandsia. See Spanish moss 

 Timber, *107~110 

 Timber supply, 112 

 Timothy, pistil of, 139* 

 Timothy, variation in, 174, 175* 

 Tolerant and intolerant trees, 113 

 Toxins, 212 

 Tracheids, 109 

 Transpiration, 22, 23, 79-83 

 Transportation of foods, 40, 42, 43 

 Tree ferr- 270 

 Tree-growing, *1 14-118 

 Trees, 12, 43, 44, 60, 61, 66, 67,78, 79, 



97*, 98*. See also Forestry 

 Tube nucleus, 135* 

 Tuber, ' "*, 88* 

 Tubercles on roots, *204-207 

 Tuberculosis, 213-215 

 Tumbl' -eds, 337*, 339 



Turgidity, 23 

 Turgor, 22 

 Turpentine, 297 

 Twills, fall of, 77-79 

 Twiners, 74*, 75* 

 Typhoid, 215, 216 



Underground stems, *86-90 

 Unisexual flowers, 127* 

 Unit characters, 174 

 Uredospores, 254, 255* 

 Usnea, 249*, 261 

 Ustilago, 252*, 253, 261 



Variation, 173 



Variety, 173 



Vaucheria, "22G-228, 260, 264 



Vegetative reproduction, *87-93, 



220-222 

 Vein, 69*, 70* 

 Venus's-flytrap, 54 

 Vernation, 271, *273 

 Vessel, 64 



Violets, cleistogamous flowers of, 141* 

 Virginia creeper, 76* 



Water, absorption of , by roots,9, 10,24 



Water, movement of, 37, 42 



Water, pressure of, 24 



Water lily, flower of, 78* 



Water plants, 29*, 78* 



Water plants, leaves of, 78*, 79, 81 



Water pollination, 139 



Water roots, 29 



Water storage, *80~83 



Water supply, 209, 217 



Water supply and leaf structure, 81, 



82 



Water supply in soils, 321-323 

 Weeds, *S8S-842 



Weeds, injuries caused by, *335-337 

 Weeds, origin of, 337 

 Weeds, prevention of, 338 

 Weeds, success of, 333, 334 

 Wheat breeding, *1 77-181 

 Wheat rust, *254-256 

 White pine, 283* 

 Williams, C. G., 186 

 Willow, flowers of, 127* 

 Willow, roots of, 29 

 Willow cutting, 90* 

 Wilting, 9, 23* 

 Wind pollination, 139 

 Windbreaks, *115-118 

 Windstorms, destruction by, 61* 



