INDEX. 



983 



Wedge-roots, of Loranthus EiiropieuB, mwle 



of prowth, kc, i. 211. 

 AWtlge-shaped apical-ccll, i. 578. 

 "Weeping, of plants, explanation, i. 271. 



— in Aroid roots, i. 366. 



— of Vines, wlien most vigorous, i. 270. 

 Wellingtonia. See Sequoia gigantea. 

 Welwitschia mirabilis, in habitat, ii. 727. 



geographical distribution, ii. 726. 



West-Indian Sour-sop. SaoAnonaviurieata. 

 Wettstein, and anatomical characteristics of 



hybrids, ii. 565. 

 Wheat, setnls and heat, i. 555. 



— starch, i. 459. 



White, visibility to insects, ii. 197. 

 Wliite Hellebore. See Veratnim, 

 White Mustard. See Sinapis alba. 

 M"hite-thom. See Crat<xgus Oxyacantha. 

 Whit low- grass. See Draft«. 

 Whorl, of perianth-leaves, i. 641. 

 Whorls, sorts of, i. 397. 

 Whortleberry, Common. See Vacdnhim 



Myrtillus. 

 Wichura, hybridization of Willows, ii. 560. 

 Wigandia urens, stinging hairs, i. 441. 

 Wightia, clinging roots, i. 702, 754. 

 Wild Cress. See ^thionema. 

 Wild Pear, spines, i. 433. 

 WUI-o'-the-Wisp, and luminous mycelium, L 



503. 

 WiUow. Sec Salix. 

 Willow, Gray. See Salix incana. 

 Willow-herb. See Epilobium. 

 Willows, Alpine, Tyrol, i. 524. 

 AVind, agent in spore-dispersal, ii. 812. 



— and fruit boring, i. 618. 



— and position of leaves, I. 427. 



— and seed dispersal, ü. 447. 



— and stunted growth, i. 524. 



Wind Bent-grass. See Apera spicaventt. 

 Wind-fertilized plants, characteristics, ii.l33. 

 Wind-iKjlIination,adaptationofsiigma.ii. 151. 

 Wind-witches, ii. 850. 

 Wine-cask Fungus, i. 50S. 

 Wine-flower scent, ii. 202. 

 Wings of Papilionaceous flower, ii. 228. 

 Wititer-buds, of Aldrovaodia, i. 152. 

 Winter Cherry. See Physalis Alkekengi. 

 Winter-green. See Pyrola. 

 Winter resting of plants, i. 562. 

 Witches' Brooms and Exoascus, ii. 676. 



caused by gall-mites, ii. 548. 



cause of. U. 518. 



on Abies pectinata, ii. 526, 



on various trees, ii. 527. 



Wolffia, rootless, ii. 745. 



Wood, ascent of sap through, i 274. 



— changes due to attack of hyphaj, i. 167. 



— longitudinal splitting in twiners and 



climbers, i. 733. 



— "luminous", i. 502. 



— of host, effect of LangsdorflBa on, i. 187. 

 Wood-ash, effect on Mosses, Grasses, Poly- 



gonaceous and Cruciferous plants, i. 74. 



Woodbine, Alpine. See Lonxcera Alpigena. 



Wooden Pear. Sec Xylomdum pyriforme. 



Wood-parenchyma, i. 469. 



AVoodniff. See Asperula odorata. 



Wood-sorreL See Oxalis, 



Wood-vessels and cell, views regarding func- 

 tion, i. 276. 



Woody fibres, nature of. i. 726. 



Woody stem, characteristics, i. 715. 



Woolly hairs, nature of, L 320. 



Wormwootl, Common. See Artemisia Ab- 



sy lithium. 

 Wormwoods, hairj- covering in summer, i. 319. 

 Woundwort. See Stachys. 

 Wracks. Seo Fticacav. 

 Wraugelia, luminosity, i. 388. 



X. 



Xanthidium aculeatum, ii. 492. 655. 

 Xanthidium octocorno, ii. 492. 

 Xanthium, protogynoua, ii. 313. 

 Xanthium spinosuni, and cattle, i. 451. 

 fruits and dissemination, i. 615. 



— — hooked capitulum, ii. 873. 

 Xanthophyll, from chlorophyll, i. 372. 

 Xanthorrhea, caudei, i. 714. 



— mode of growth, i. 659. 

 Xanthorrhea hastilis.height, PI. XVI., ii. 731. 

 Xenogamy, in hybrids, ii. 583. 



— nature of, ii. 317. 



Xeranthcmum, hairy covering in summer, i. 



319. 

 Xeranthemum annuum, coloured bracts, ii. 



183. 

 Xylaria Hypoxylon, ii. 679. 



stroma, ii. 681. 



Xylaria polymorpha, stroma, ii. 681. 

 Xylocopa violacea and Spartium scoparium, 



ii. 267. 

 Xylomelum pyriforme, fruit, ii. 430, 431, 751. 

 ^ — protecting pericarp, ii. 449. 



Yakutsk, winter cold, i. 544. 



Yeast fermentation, nature of, ii. 519. 



— ferment of, i. 465. 



Yeasts. See also Saccharomijces. 



— fermentative, i. 505. 



Yellow granules of autumn leaves, i. 485. 

 Yellow-rattle. See Rhinanthns Ci'ista-galli. 

 Yellow VetchUng. See Lathyrus Apfuica. 

 Yew. See Taxus baccata. 

 Ytang perfume of Zaluzianskia, ii. 242. 

 "York and Lancaster" Rose, ii. 568. 

 Yucca, acicular leaves, i. 434. 



— and insect visits, ii. 222. 



— and night visitors, ii. 196. 



— caudex. i. 714. 



— cotyledon in germination, i. 606. 



— fertilization by Moths and advantage to 



the insects, i. 255. 



— infertihty in Europe, ii. 403. 



— mode of growth, i. 660. 



— phyllotaxis, i. 402. 



— pollination by Prouuba yuccasella. ii. 157, 



245. 



Yucca aloefolia, fertilization, ii. 158. 159. 



fertilization, geographical di.stribution, 



ii. 159. 



Yucca angustifolia, pollen-grains, ii. 97. 



Yucca gloriosa. i. 659 ; ii. 732. 



Yucca Treculeana, fertilization and geo- 

 graphical distribution, ii. 159. 



Yucca Whipple), non-fruitiug, ii. 158. 



Zaluzianskia lychnldoa, pollination and 



scent, ii. 202, 241. 

 Zamia, cotyledon in germination, i. 606. 



— spiny leaves, i. 438. 

 Zannichollia, moncuclous, ii. 297. 



— pollen and pollination, ii, 105. 



— root origin, i. 766. 

 Zanthoxylon, reserve-buds, ii. 32. 



Zea Mays, and Ustilago Maydia, ii. 524, 675. 



monoecious, ii. 297. 



protogynoua, ii. 313. 



stilt-roots, mechanical tissue, i. 762. 



vitality of 8permatopl.i.<tni, ii. 96. 



&c., reared in artificial culture solu- 

 tion, i. 100. 

 Zero of growth, i. 561. 

 Zigzag stem, i. 658. 

 Zingiber, venation, i. 634. 

 Zingiberaccje, stamens, ii. 736. 

 Zinnia hybrida, colour-contrast in capitulum, 



ii. 191. 

 Zonotrichia, in waterfalls, i. 79. 



— movement of, i. 39. 



Zoogloea, bacterial condition, ii. 622. 



— of Micrococcus prodigiosus, ii. 624. 

 Zoophytes, appropriateness of name, ii. 469. 

 Zoospore, eye-spot, ii. 629. 



— of Botrj'dium, ii. 642. 



— of Vaucheria, ii. 644. 



Zoospore formation, in llydrodictyon. ii. G41. 

 Zoosporeae, ii. 606. 

 Zoospores, ii. 17. 



— behaviour towards light, i. 382. 



— of Chlorophycea», ii. 628. 

 Zostera, i. 77. 



— habit, &c,, i. 666. 



— pollen and pollination, ii. 104, I0& 

 Zostera marina, ii. 738. 



Zygfena, and honey scent, ii. 207. 

 Zygnema, cell-division, i. 577, 581. 



— characteristics, ii. 658. 



— chlorophyll bodies, cf. PI. I., i. 373. 



— conjugation, ii. 658. 

 Zygnema pectinatum, PI. I. 

 Zygnemacese, ii. 658. 



— chromatophores, ii. 654. 



— conjugation, ii. 55. 

 ZygnemefB, filaments, i. 586. 

 Zygnemoideae. characteristics, ii. 654. 

 ZygogoDium, nature of, ii. 54. 

 Zygomorphic symmetry, ii. 229. 

 Zygomycetes, characteristics, ii. 673. 

 Zygospore investment, in Mortierelleio, ii. 674 



— of Mucor, ii. 673. 



— of Mucorini, ii. 481. 484. 

 Zygote, nature of, ii. 54. 



— of Botrydium, ii. G42. 



— of Chloroehytriuni, ii. 637. 



— of Chlorophyceaj, ii. 628. 



— of Conjugataj, ii. 654. 



— of DesmiilB, ii. 654. 



— of llydrodictyon, ii. 641. 



— of Pediaatrum. ii. 639. 



— of Phyllobium, i.'638. 



— of Sjiirogyra, ii. 658. 



— of Volvox globator, ii. 635. 

 Zygotes of Ulotbrix zonata, ii. 648- 

 Zygozoosporo, formation, il. 632. 

 Zygozooaporcs, of Ohlorochytrium, ii. 637. 



— of Phytl'.biinn, ii. 638. 



— of Stcphanuäphaira, &c.. U. 632. 



END OF VOL. IL 



