502 
INDEX. 
VOLCANIC. 
Volcanic islands, denudation of, 285. 
Vulture, naked skin on head, 197. 
W. 
Wading-birds, 386. 
Wallace, Mr., on origin of species, 2. 
-, on law of geographical distribu¬ 
tion, 355. 
-, on the Malay Archipelago, 395. 
Wasp, sting of, 202. 
Water, fresh, productions of, 383. 
Water-hen, 185. 
Waterhouse, Mr., on Australian mar¬ 
supials, 116. 
-on greatly developed parts being 
variable, 150. 
-, on the cells of bees, 225. 
-, on general affinities, 429. 
Water-ouzel, 185. 
Watson, Mr. H. C., on range of varieties 
of British plants, 58. 
-•, on acclimatisation, 140. 
-, on flora of Azores, 363. 
-, on Alpine plants, 368, 376. 
-, on rarity of intermediate varie¬ 
ties, 176. 
Weald, denudation of, 285. 
Web of feet in water-birds, 185. 
West Indian islands, mammals of, 396. 
Westwood on species in large genera 
being closely allied to others, 57. 
-- on the tarsi of Engidse, 157. 
-on the antennae of hymenopterous 
insects, 415. 
Wheat, varieties of, 113. 
White Mountains, flora of, 365. 
Wings, reduction of size, 134. 
ZEBRA. 
Wings of insects homologous with bran- 
chise, 191. 
-, rudimentary, in insects, 450. 
Wolf crossed with dog, 214. 
-of Falkland Isles, 394. 
Wollaston, Mr., on varieties of insects, 
48. 
-, on fossil varieties of land-shells 
in Madeira, 52. 
■-, on colours of insects on sea-shore, 
132. 
-, on wingless beetles, 135. 
-, on rarity of intermediate varie¬ 
ties, 176. 
-, on insular insects, 389. 
-, on land-shells of Madeira, natu¬ 
ralised, 402. 
Wolves, varieties of, 90. 
Woodpecker, habits of, 184. 
-, green colour of, 197. 
Woodward, Mr., on the duration of 
specific forms, 294. 
——, on the continuous succession of 
genera, 316. 
-, on the succession of types, 339. 
World, species changing simultaneously 
throughout, 322. 
Wrens, nest of, 243. 
Y. 
Youatt, Mr., on selection, 31. 
-, on sub-breeds of sheep, 36, 
-, on rudimentary horns in young 
cattle, 454. 
Z. 
Zebra, stripes on, 163. 
THE END. 
LOKIX>N .* PRINTED BY WILLIAM CLOWES AND SONS, STAMFORD STREET, 
AND CHARING CROSS. 
