Abyssinia, plants of, 326. Acclimatisation, 127. Affinities of extinct species, 287. of organic beings, 358. Agassiz on Amblyopsis, 127. on groups of species suddenly ap- on embryological succession, 295. on embryological characters, 364. Algae of New Zealand, 327. Artichoke, Jerusalem, 129 Ateuchus, 123. Audubon on habits of frigate-bird, 160 Australia, animals of, 108, dogs of, 192. extinct animals of, 296. Azara on flies destroying cattle, 70. Babington, Mr., on British plants, 49. America, North, productions allied to Balancement of growth, 133. Amblyopsis, blind fish, 127. those of Europe, 323. boulders and glaciers of, 325. South, no modern formations on west coast, 254. Ammonites, sudden extinction of, 281. Ancylus, 336. Animals, not domesticated from being domestic, descended from several acclimatisation of, 129. of Australia, 108. Bamboo with hooks, 176. Barberry, flowers of, 92. Barrande, M., on Silurian colonies, 274. on affinities of ancient species, 288. queen, killing rivals, 180. with thicker fur in cold climates, 122. Bees fertilising flowers, 71. blind, in caves, 125. extinct, of Australia, 296. Anomma, 213. Antarctic islands, ancient flora of, 347. Antirrhinum, 145. Ants attending aphides, 188. slave-making instinct, 195. Ants, neuter, structure of, 209. Aphides attended by ants, 188. Aphis, development of, 384. Apteryx, 163. Arab horses, 38. Aralo-Caspian Sea, 296. Archiac, M. de, on succession of species, 284. Birds of Madeira, Bermuda, and Gala- | Classification, 360. pagos, 340. song of males, 84. transporting seeds, 315. waders, 337. wingless, 123, 163. with traces of embryonic teeth, 391. Bizcacha, 305. affinities of, 373. Bladder for swimming in fish, 170. Blyth, Mr., on distinctness of Indian cat- on striped Hemionus, 147. Boar, shoulder-pad of, 84. Borrow, Mr., on the Spanish pointer, 38. Brent, Mr., on house-tumblers, 191. on hawks killing pigeons, 315. Bronn on duration of specific forms, 257. Cabbage, varieties of, crossed, 93. Canary-birds, sterility of hybrids, 223. Cats, with blue eyes, deaf, 18. variation in habits of, 86. curling tail when going to spring, 179. destroyed by flies in La Plata, 70. Cave, inhabitants of, blind, 125. Cephalopoda, development of, 384. Cetacea, teeth and hair, 131. Ceylon, plants of, 326. Chalk formation, 282. Characters, divergence of, 103. sexual, variable, 141. adaptive or analogical, 371. Charlock, 74. Checks to increase, 66. mutual, 69. Chickens, instinctive tameness of, 192. Chthamalus, cretacean species of, 266. domestic products, 42. to natural selection, 95. Cirripedes capable of crossing, 95. their ovigerous frena, 172. larvae of, 883. Creation, single centres of, 307. Crosses, reciprocal, 228. Crossing of domestic animals, importance unfavourable to selection, 96. Cryptocerus, 211. Ctenomys, blind, 125. Cuvier on conditions of existence, 184. Dana, Prof., on blind cave-animals, 126. on crustaceans of New Zealand, 327. De Candolle on struggle for existence, 61. on general affinities, 374. Alph, on low plants, widely dis- on widely-ranging plants being va on naturalisation, 107. on winged seeds, 133. on Alpine species suddenly becom on distribution of plants with large on vegetation of Australia, 330. on insular plants, 339. Degradation of coast rocks, 248. of oldest rocks, 269. Development of ancient forms, 203. Disuse, effects of, under nature, 122. Division, physiological, of labour, 107. domestic instincts of, 190. proportions of, when young, 386. as bearing on natural selection, 102. Eye, structure of, 167. correction for aberration, 180. Eyes reduced in moles, 125. Fabre, M., on parasitic sphex, 195. Falconer, Dr., on naturalisation of plants on fossil crocodile, 274. on elephants and mastodons, 292. Falkland Island, wolf of, 343. Faunas, marine, 304. Fear, instinctive, in birds, 189. Feet of birds, young molluscs adhering to, teleostean, sudden appearance of, 267 fresh-water, distribution of, 335. Fishes, ganoid, now confined to fresh electric organs of, 172. ganoid, living in fresh water, 281. of composite and umbelliferæ, 131. on abrupt range of shells in depth, 157. on poorness of paleontological col- on continuous succession of genera, on continental extensions, 311. on distribution during glacial period, on parallelism in time and space,356 Formica rufescens, 195. sanguinea, 195. flava, neuter of, 212. Frena, ovigerous, of cirripedes, 172. Fries on species in large genera being Frogs on islands, 342. Fruit-trees, gradual improvement of, 40. varieties of, acclimatised in United Fuci, crossed, 228. Fur, thicker in cold climates, 132. Galapagos Archipelago, birds of, 340. Galeopithecus, 162. Game, increase of, checked by vermin, 67. on reciprocal crosses, 228. on crossed maize and verbascum, on comparison of hybrids and mon Geese, fertility when crossed, 224. upland, 166. Genealogy important in classification, 370. Isidore, on variability of repeated on correlation in monstrosities, 18. Geoffroy on correlation, 131. on variable parts being often mon- Geographical distribution, 302. Geology, future progress of, 421. Giraffe, tail of, 174. 318. Godwin-Austen, Mr., on the Malay Archi- Goethe on compensation of growth, 133. Gould, Dr. A., on land-shells, 345. Mr., on colours of birds, 121. on birds of the Galapagos, 347. on distribution of genera of birds, Gourds, crossed, 238. Grafts, capacity of, 231. Gray, Dr. Asa, on trees of United States, on naturalised plants in the United on rarity of intermediate varieties, Hazel-nuts, 313. Hearne on habits of bears, 165. Heath, changes in vegetation, 70. Heer, O., on plants of Madeira, 100. Helix pomatía, 346. Helosciadium, 313. Hemionus, striped, 147. Herbert, W., on struggle for existence, 61. on sterility of hybrids, 220. Hermaphrodites crossing, 91. Heusinger on white animals not poisoned Hewitt, Mr., on sterility of first crosses, 233. Himalaya, glaciers of, 324. plants of, 326. Hippeastrum, 221. Holly-trees, sexes of, 88. Hollyhock, varieties of, crossed, 239. Hooker, Dr., on trees of New Zealand, 94. Hooker, Dr., on acclimatisation of Hima on flowers of umbelliferæ, 132. on vegetation at the base of the on plants of Tierra del Fuego, 326, on Australian plants, 327, 347. on relations of flora of South Amer- on flora of the Antarctic lands, 341, on the plants of the Galapagos, 341, 347. Hooks on bamboos, 176. to seeds on islands, 342. Horner, Mr., on the antiquity of Egyp Horns, rudimentary, 394. Horse, fossil, in La Plata, 278. Horses destroyed by flies in La Plata, 70. proportions of, when young, 386. P., on reason blended with instinct, on habitual nature of instincts, 186. on Melipona domestica, 200. Humble-bees, cells of, 200. Hunter, J., on secondary sexual charac- Hutton, Captain, on crossed geese, 224. on embryological succession, 295. on the development of aphis, 384. Hydra, structure of, 170. Jussieu on classification, 363. Kentucky, caves of, 125. Kerguelen-land, flora of, 331, 347. Kirby on tarsi deficient in beetles, 123. Knight, Andrew, on cause of variation, 14. on sterility of hybrids, 218. on crossed varieties of nicotiana, 239. Lamarck on adaptive characters, 371. of Madeira, naturalised, 350. Languages, classification of, 367. Larva, 382. Laurel, nectar secreted by the leaves, 88. Laws of variation, 120. Leech, varieties of, 73. Matthiola, reciprocal crosses of, 228. Melipona domestica, 200. Metamorphism of oldest rocks, 269. Leguminosa, nectar secreted by glands, 88. Mice destroying bees, 72. Lepidosiren, 100, 288. Life, struggle for, 60. Lingula, Silurian, 268. Lion, mane of, 84. Linnæus, aphorism of, 360. young of, striped, 382. Lobelia fulgens, 71, 92. Lobelia, sterility of crosses, 221. Lowness of structure connected with va- Lowness, related to wide distribution, 353. on resemblance of child to parent, Lund and Clausen on fossils of Brazil, 296. on modern changes of the earth, 90. on strata beneath Silurian system, 268. on the imperfection of the geological on the appearance of species, 273. on tertiary formations of Europe and on parallelism of tertiary formations, on transport of seeds by icebergs, on great alternations of climate, 332. on land-shells of Madeira, 350. Macleay on analogical characters, 371. beetles of, wingless, 124. acclimatisation of, 128. Migration, bears on first appearance of fossils, 259. Miller, Prof., on the cells of bees, 201. Missel-thrush, 74. Misseltoe, complex relations of, 11. Mocking-thrush of the Galapagos, 350. Moles, blind, 125. Mongrels, fertility and sterility of, 236. Mons, Van, on the origin of fruit-trees, 32. Mozart, musical powers of, 186. Müller, Dr. F., on Alpine Australian Murchison, Sir R., on the formations of on azoic formations, 268. Nails, rudimentary, 393. Natural history, future progress of, 419. system, 360. Naturalisation of forms distinct from the |