INDEX 



285 



Violets, pollination of, 79 



seeds of, 184 

 Virginia creeper, adventitious roots of, 

 92, 93 

 air roots of, 24 



cowslip, 233 

 Viscimi, 104 

 Vitacese, 93 

 Vitis cordifolia, 224 

 Volcanic dust, 205 



W 



Waksman, S. a., 157, 158 

 Waller, A. E., 254, 261 

 Walnut, pollination of, 67, 68 

 Wasps, 77 

 Water, 29, 32, 38, 159-165 



and root growth, 19 



and distribution of plants, 163, 165 



arum, pollination of, 84 



crowfoot, 229 



fern, 24 



horehound, 229 



hyacinth, air spaces in, 46 



in leaves, 52 



in roots, 19 



influence on conductive tissue, 29 

 on leaf form, 52 

 on stem form, 38 



lily, 30, 229, 236 



mechanical effects of, 161 



plantain, 224 



plants, 24 



pollination, 71, 72 



table, 146 

 Waterman, W. G., 26, 231 

 Weaver, J. E., 26, 219, 260, 261 

 Weir, James R., 103, 104 

 Wells, B. W., 62, 63, 254 

 Wheat, 21, 22 



grass, 19 

 Wherry, Edgar T., 158 

 Whitaker, E. S., 26 

 White alkali, 152 



cedar, 245 



clover flowers, 80, 81 



fir, 244 

 Whitford, H. N., 219 

 Wild grape, 90 



lettuce, 122 



Wilde, S. A., 158 

 Williams, A. B., 254 

 Willow, 39, 185, 216, 229 



galls on, 112 



sandbar, 222 

 Wilson, K., 26 

 Wilting coefficient, 147 

 Wind, 141-143 



pollinated flowers, 67-71 

 Winter season, 232 



wet season, 235 

 Winterberry, 230 

 Witches' broom, 112 

 Wodehouse, R. P., 72 

 Woffenden, Lettice M., 40 

 Wolfe, T. K., 237 

 Wolffia, roots of, 24 

 Wood, J. G., 179 

 Woodland communities, 246-247 

 Woodroof, J. G., 26 

 Woodroof, N. C., 26 

 Wormwood, 220, 221 

 Wylie, R. B., 72 



XantUum, 186, 224 

 Xenogamy, 65, 67 

 Xerarch successions, 220, 222 

 Xeric, 159 



habitats, plants of, 169-173 

 Xerism, 160 

 Xerophytes, 159 



characteristics of, 169-173 

 Xylaria, 60 

 Xylem, 29, 31 



Yapp, R. H., 202 

 Yellow poplar, 239 

 Yocum, W. W., 26 

 Yucca, 240, 252 

 pollination of, 84 



ZiMMERMANN, P. W., 129 



Zinc, 149 



Zon, Raphael, 271 



