506 



INDEX 



Vaccinium, 472 



Vacuoles, i, 2, 3, 60, 217 



Valerian, 483 



Valves, of diatoms, 170 



Vapor, from plants, 24 



Variation, 105, 144, 176, 190, 197, 



218, 280, 312-313, 320, 388 

 Variegated plants, 14, 32 

 Vascular bundles, II, 12, 16, 76, 77, 



78, 79, 80, 97, 312, 314, 323, 324, 



337. 342- 354 

 Vaucheria, 195, 196 

 Veins, 7, 9, 1 1, 301, 302, 312 

 Velamen, 422 

 Veltheimia, 402 

 Velum, 260, 261 

 Venation, 7, 400, 401, 426, 427 

 Veratrum, 416 

 Vernonia, 491 

 Versatile anthers, 408 

 Vessels, 79, 80 

 Viburnum, 481, 482 

 Vitis, 461 

 Volva, 261 

 Volvocales, 174 

 Volvox, 1 80, 181 



Wallace's Law, 423 



Wall cells, 277, 318, 358, 392 



Walnut order, 433 



Ward, 24 



Water-bloom, 165 



Water, action on rock, 49 



capillary, 50 



composition of, 12 



gravitational, 50 



hygroscopic, 50 



lily, 398, 438 



mould, 218 



net, 184 



Watering of plants, 55 

 Wax of epidermis, 37, 39 

 Weeds, 445 

 Willow, 381, 430 



order, 429 



Wilting, cause of, 24 

 Wind, pollination by, 388, 404, 433 



458 



Winged fruits. 373, 458 

 Wings, of flowers, 451-453 

 Witches' broom, 256 

 Wolffia, 410 

 Wood, heart, 95 



oak, 95, 427 



pine, 363 



sap, 95 



sections, 93, 94, 95 



spring, 91,92, 95 



summer, 91, 92 

 Woodsia, 328 

 Woodwardia, 326, 328 

 Work of plants, 15 

 Working of ponds, 165 



Xanthidium, 188 



Xerophytes, 39, 45 



Xylaria, 239, 241 



Xylem, 59, 76, 78, 79, 91, 314-31$ 



Yamanouchi, 215 

 Yeast, 248, 249 

 Yucca, 419 



Zamia, 353, 354- 355. 356 

 Zooglea, 155 

 Zoospore, 151, 152 

 Zygnema, 185, 186 

 Zygnematales, 185 

 Zygomorphic, 387 



