Varieties, 78, 247. Varieties of soil, 56. _Vaucheria_, 139, 140. Vegetable acids, 48. Vertebrata, 108. _Verticillium_, 145, 236. _Viburnum_, 214. Vine, 110, 149, 156, 162, 164, 169, 171, 189, 190, 191, 222, 248, 268. Vine disease, 143. Vivipary, 257, 258. Walnut, 190, 209, 253. Want of air, 100. Washing leaves, etc., 161. Wasp-flies, 165. Wasps, 145. Water, 272. Water and insects, 161. Water-culture, 65. Water in soil, 103. Waterlogging, 181. Weaving of fungi, 190. Webs, 190, 254. Weeding, 105. Weeds, 69, 111, 113, 165, 229, 249. Weevils, 248. Wet feet, 181. Wheat, 169, 171, 172, 176, 179, 180, 182, 183, 230, 248. Wheat rust, 86, 122, 146, 166, 169, 176. White spots, 186, 187. Willow, 206, 207, 219, 223, 233, 259. Willow beetle, 208. Wilting, 179, 181, 235, 249. Wind, 106, 142, 144, 153, 184, 209, 229. Wire-worms, 109, 181. Witches' brooms, 116, 222, 224. Wood, 124. Wood-ashes, 161. Woodbine, 112, 210. Wood-boring, 204, 205. Woodlice, 164. Wood-nodules, 225. Wood-wasps, 206. Woolly-aphis, 219, 223. Worms, 109, 142, 144, 194, 238. Wounds, 108, 139, 194, 204, 207, 213, 260, 263, 269. Wound-cork, 195. Wound-fever, 123. Wound-fungi, 203, 204, 240. Wound-gum, 125. Wound-wood, 124. Wrens, 165. Wrinkling, 253. _Xenia_, 267. _Xyloma_, 88. Yeasts, 134, 172, 231, 233. Yellowing, 179, 181, 182, 184. Yellow leaves, 89. Yellow spots, 186, 187, 188, 253. Zoospores, 151. GLASGOW: PRINTED AT THE UNIVERSITY PRESS BY ROBERT MACLEHOSE AND CO. MACMILLAN AND CO.'S WORKS ON BOTANY. BY THE SAME AUTHOR. Crown 8vo. Price 6s. Timber and Some of its Diseases. By H. MARSHALL WARD, D.Sc., F.R.S., F.L.S., Fellow of Sidney Sussex College, and Professor of Botany in the University of Cambridge. Illustrated. _MANCHESTER EXAMINER._--"The subject as a whole is one which is little understood in England, and Professor Marshall Ward's work cannot fail to be useful. The student will be much helped by the numerous illustrations." _GARDENER'S CHRONICLE._--"This is a book whose appearance we hail with great satisfaction. . . . We heartily recommend its perusal to those concerned." =The Study of the Biology of Ferns by the Collodion Method.= For Advanced and Collegiate Students. By GEORGE F. ATKINSON, Ph.B., Associate Professor of Cryptogamic Botany in Cornell University. 8vo. 8s. 6d. net. =On British Wild Flowers considered in Relation to Insects.= By LORD AVEBURY, F.R.S., D.C.L., LL.D. Illustrated. Cr. 8vo. 4s. 6d. =Flowers, Fruits, and Leaves.= With illustrations. By LORD AVEBURY, F.R.S., D.C.L., LL.D. Cr. 8vo. 4s. 6d. =Lessons with Plants.= By Prof. L. H. BAILEY. Cr. 8vo. 7s. 6d.