[307].
—, upland, [142].
Geikie, Mr., on subaërial denudation, [267].
Genealogy, important in classification, [369].
Generations, alternate, [387].
Geoffroy St. Hilaire, on balancement, [117].
—, on homologous organs, [382].
—, , Isidore, on variability of repeated parts, [118].
—, on correlation, in monstrosities, [9].
—, on correlation, [115].
—, on variable parts being often monstrous, [122].
Geographical distribution, [316].
Geography, ancient, [427].
Geology, future progress of, [427].
—, imperfection of the record, [427].
Gervais, Prof., on Typotherium, [302].
Giraffe, tail of, [157].
—, structure of, [177].
Glacial period, [330].
—, affecting the North and South, [335].
Glands, mammary, [189].
Gmelin, on distribution, [330].
Godwin-Austin, Mr., on the Malay Archipelago, [280].
Goethe, on compensation of growth, [117].
Gomphia, [174].
Gooseberry, grafts of, [246].
Gould, Dr. Aug. A., on land-shells, [353].
Gould, Mr., on colours of birds, [107].
—, on instincts of cuckoo, [214].
—, on distribution of genera of birds, [358].
Gourds, crossed, [258].
Graba, on the Uria lacrymans, [72].
Grafting, capacity of, [245], [246].
Granite, areas of denuded, [274].
Grasses, varieties of, [88].
Gray, Dr. Asa, on the variability of oaks, [40].
—, on man not causing variability, [62].
—, on sexes of the holly, [74].
—, on trees of the United States, [79].
—, on naturalised plants in the United States, [89].
—, on æstivation, [174].
—, on Alpine plants, [330].
—, on rarity of intermediate varieties, [136].
Gray, Dr. J.E., on striped mule, [128].
Grebe, [142].
Grimm, on asexual reproduction, [387].
Groups, aberrant, [378].
Grouse, colours of, [66].
—, red, a doubtful species, [38].
Growth, compensation of, [117].
Günther, Dr., on flat-fish, [187].
—, on prehensile tails, [189].
—, on the fishes of Panama, [317].
—, on the range of fresh-water fishes, [343].
—, on the limbs of Lepidosiren, [399].
Haast, Dr., on glaciers of New Zealand, [335].
Habit, effect of, under domestication, [8].
—, effect of, under nature, [108].
—, diversified, of same species, [141].
Häckel, Prof., on classification and the lines of descent, [381].
Hair and teeth, correlated, [115].
Halitherium, [302].
Harcourt, Mr. E.V., on the birds of Madeira, [348].
Hartung, M., on boulders in the Azores, [328].
Hazel-nuts, [325].
Hearne, on habits of bears, [141].
Heath, changes in vegetation, [55].
Hector, Dr., on glaciers of New Zealand, [335].
Heer, Oswald, on ancient cultivated plants, [13].
—, on plants of Madeira, [83].
Helianthemum, [174].
Helix, resisting salt water, [353].
Helix pomatia, [353].
Helmholtz, M., on the imperfection of the human eye, [163].
Helosciadium, [325].
Hemionus, striped, [128].
Hensen, Dr., on the eyes of Cephalopods, [152].
Herbert, W., on struggle for existence, [49].
—, on sterility of hybrids, [238].
Hermaphrodites crossing, [76].
Heron eating seed, [346].
Heron, Sir R., on peacocks, [70].
Heusinger, on white animals poisoned by certain plants, [9].
Hewitt, Mr., on sterility of first crosses, [249].
Hildebrand, Prof., on the self-sterility of Corydalis, [238].
Hilgendorf, on intermediate varieties, [275].
Himalaya, glaciers of, [335].
—, plants of, [337].
Hippeastrum, [238].
Hippocampus, [189].
Hofmeister, Prof., on the movements of plants, [197].
Holly-trees, sexes of, [73].
Hooker, Dr., on trees of New Zealand, [78].
—, on acclimatisation of Himalayan trees, [112].
—, on flowers of umbelliferæ, [116].
—, on the position of ovules, [172].
—, on glaciers of Himalaya, [335].
—, on algæ of New Zealand, [338].
—, on vegetation at the base of the Himalaya, [338].
—, on plants of Tierra del Fuego, [336].
—, on Australian plants, [337], [355].
—, on relations of flora of America, [340].
—, on flora of the Antarctic lands, [341], [354].
—, on the plants of the Galapagos, [349], [354].
—, on glaciers of the Lebanon, [335].
—, on man not causing variability, [62].
—, on plants of mountains of Fernando Po, [337].
Hooks on palms, [158].
—, on seeds, on islands, [349].
Hopkins, Mr., on denudation, [274].
Hornbill, remarkable instinct of, [234].
Horns, rudimentary, [400].
Horse, fossil in La Plata, [294].
—, proportions of, when young, [392].
Horses destroyed by flies in Paraguay, [56].
—, striped, [128].
Horticulturists, selection applied by, [23].
Huber on cells of bees, [224].
Huber, P., on reason blended with instinct, [205].
—, on habitual nature of instincts, [206].
—, on slave-making ants, [216].
—, on Melipona domestica, [220].
Hudson, Mr., on the Ground-woodpecker of La Plata, [142].
—, on the Molothrus, [215].
Humble-bees, cells of, [221].
Hunter, J., on secondary sexual characters, [119].
Hutton, Captain, on crossed geese, [240].
Huxley, Prof., on structure of hermaphrodites, [79].
—, on the affinities of the Sirenia, [302].
—, on forms connecting birds and reptiles, [302].
—, on homologous organs, [386].
—, on the development of aphis, [390].
Hybrids and mongrels compared, [259].
Hybridism, [235].
Hydra, structure of, [147].
Hymenoptera, fighting, [69].
Hymenopterous insect, diving, [142].
Hyoseris, [173].
Ibla, [118].
Icebergs transporting seeds, [329].
Increase, rate of, [50].
Individuals, numbers favourable to selection, [80].
—, many, whether simultaneously created, [322].
Inheritance, laws of, [10].
—, at corresponding ages, [10], [67].
Insects, colour of, fitted for their stations, [66].
—, sea-side, colours of, [107].
—, blind, in caves, [110].
—, luminous, [151].
—, their resemblance to various objects, [181].
—, neuter, [2320].
Instinct, [205].
—, , not varying simultaneously with structure, [229].
Instincts, domestic, [209].
Intercrossing, advantages of, [76], [251].
Islands, oceanic, [347].
Isolation favourable to selection, [81].
Japan, productions of, [334].
Java, plants of, [337].
Jones, Mr. J.M., on the birds of Bermuda, [348].
Jordain, M., on the eye-spots of star fishes, [144].
Jukes, Prof., on subaërial denudation, [267].
Jussieu on classification, [367].
Kentucky, caves of, [111].
Kerguelen-land, flora of, [341], [354].
Kidney-bean, acclimatisation of, [114].
Kidneys of birds, [115].
Kirby, on tarsi deficient in beetles, [108].
Knight, Andrew, on cause of variation, [5].
Kölreuter, on intercrossing, [76].
—, on the barberry, [77].
—, on sterility of hybrids, [237].
—, on reciprocal crosses, [243].
—, on crossed varieties of nicotiana, [258].
—, on crossing male and hermaphrodite flowers, [397].
Lamarck, on adaptive characters, [373].
Lancelet, [99].
—, , eyes of, [145].
Landois, on the development of the wings of insects, [148].
Land-shells, distribution of, [353].
—, of Madeira, naturalised, [357].
—, resisting salt water, [353].
Languages, classification of, [371].
Lankester, Mr. E. Ray, on longevity, [169].
—, on homologies, [385].
Lapse, great, of time, [266].
Larvæ, [388], [389].
Laurel, nectar secreted by the leaves, [73].
Laurentian formation, [287].
Laws of variation, [106].
Leech, varieties of, [59].
Leguminosæ, nectar secreted by glands, [73].
Leibnitz’ attack on Newton, [421].
Lepidosiren, [83], [303].
—, , limbs in a nascent condition, [398], [399].
Lewes, Mr. G.H., on species not having changed in Egypt, [169].
—, on the Salamandra atra, [397].
—, on many forms of life having been at first evolved, [425].
Life, struggle for, [49].
Lingula, Silurian, [286].
Linnæus, aphorism of, [365].
Lion, mane of, [69].
—, young of, striped, [388].
Lobelia fulgens, [57], [77].
Lobelia, sterility of crosses, [238].
Lockwood, Mr., on the ova of the Hippocampus, [189].
Locusts transporting seeds, [327].
Logan, Sir W., on Laurentian formation, [287].
Lowe, Rev. R.T., on locusts visiting Madeira, [327].
Lowness, of structure connected with variability, [118].
—, related to wide distribution, [359].
Lubbock, Sir J., on the nerves of coccus, [35].
—, on secondary sexual characters, [124].
—, on a diving hymenopterous insect, [142].
—, on affinities, [280].
—, on metamorphoses, [386], [389].
Lucas, Dr. P., on inheritance, [9].
—, on resemblance of child to parent, [261].
Lund and Clausen, on fossils of Brazil, [310].
Lyell, Sir C., on the struggle for existence, [49].
—, on modern changes of the earth, [75].
—, on terrestrial animals not having been developed on islands, [180].
—, on a carboniferous land-shell, [271].
—, on strata beneath Silurian system, [287].
—, on the imperfection of the geological record, [289].
—, on the appearance of species, [289].
—, on Barrande’s colonies, [291].
—, on tertiary formations of Europe and North America, [298].
—, on parallelism of tertiary formations, [301].
—, on transport of seeds by icebergs, [328].
—, on great alternations of climate, [342].
—, on the distribution of fresh-water shells, [345].
—, on land-shells of Madeira, [357].
Lyell and Dawson, on fossilized trees in Nova Scotia, [278].
Lythrum salicaria, trimorphic, [254].
Macleay, on analogical characters, [373].
Macrauchenia, [302].
McDonnell, Dr., on electric organs, [150].
Madeira, plants of, [83].
—, beetles of, wingless, [109].
—, fossil land-shells of, [311].
—, birds of, [348].
Magpie tame in Norway, [209].
Males, fighting, [69].
Maize, crossed, [257].
Malay Archipelago, compared with Europe, [280].
—, mammals of, [352].
Malm, on flat-fish, [186].
Malpighiaceæ, small imperfect flowers of, [173].
Malpighiaceæ, [367].
Mammæ, their development, [189].
—, rudimentary, [397].
Mammals, fossil, in secondary formation, [283].
—, insular, [351].
Man, origin of, [428].
Manatee, rudimentary nails of, [400].
Marsupials of Australia, [90].
—, , fossil species of, [382].
—, , structure of their feet, [310].
Martens, M., experiment on seeds, [325].
Martin, Mr. W.C., on striped mules, [129].
Masters, Dr., on Saponaria, [174].
Matteucci, on the electric organs of rays, [150].
Matthiola, reciprocal crosses of, [244].
Maurandia, [197].
Means of dispersal, [323].
Melipona domestica, [220].
Merrill, Dr., on the American cuckoo, [212].
Metamorphism of oldest rocks, [287].
Mice destroying bees, [56].
—, acclimatisation of, [113].
—, tails of, [189].
Miller, Prof., on the cells of bees, [221], [224].
Mirabilis, crosses of, [243].
Missel-thrush, [59].
Mistletoe, complex relations of, [2].
Mivart, Mr., on the relation of hair and teeth, [115].
—, on the eyes of cephalopods, [151].
—, various objections to Natural Selection, [174].
—, on abrupt modifications, [201].
—, on the resemblance of the mouse and antechinus, [373].
Mocking-thrush of the Galapagos, [357].
Modification of species, not abrupt, [424].
Moles, blind, [110].
Molothrus, habits of, [215].
Mongrels, fertility and sterility of, [255].
—, and hybrids compared, [259].
Monkeys, fossil, [284], [285].
Monachanthus, [372].
Mons, Van, on the origin of fruit-trees, [21].
Monstrosities, [33].
Moquin-Tandon, on sea-side plants, [107].
Morphology, [382].
Morren, on the leaves of Oxalis, [197].
Moths, hybrid, [240].
Mozart, musical powers of, [206].
Mud, seeds in, [345].
Mules, striped, [129].
Müller, Adolph, on the instincts of the cuckoo, [213].
Müller, Dr. Ferdinand, on Alpine Australian plants, [337].
Müller, Fritz, on dimorphic crustaceans, [35], [233].
—, on the lancelet, [99].
—, on air-breathing crustaceans, [152].
—, on climbing plants, [197].
—, on the self-sterility of orchids, [238].
—, on embryology in relation to classification, [368].
—, on the metamorphoses of crustaceans, [390], [395].
—, on terrestrial and fresh-water organisms not undergoing any metamorphosis, [394].
Multiplication of species not indefinite, [101].
Murchison, Sir, R., on the formations of Russia, [272].
—, on azoic formations, [286].
—, on extinction, [293].
Murie, Dr., on the modification of the skull in old age, [149].
Murray, Mr. A., on cave-insects, [111].
Mustela vison, [138].
Myanthus, [372].
Myrmecocystus, [231].
Myrmica, eyes of, [232].
Nägeli, on morphological characters, [170].
Nails, rudimentary, [400].
Nathusius, Von, on pigs, [159].
Natural history, future progress of, [426].
—, selection, [62].
—, system, [364].
Naturalisation of forms distinct from the indigenous species, [89].
—, in New Zealand, [163].
Naudin, on analagous variations in gourds, [125].
—, on hybrid gourds, [258].
—, on reversion, [260].
Nautilus, Silurian, [286].
Nectar of plants, [73].
Nectaries, how formed, [73].
Nelumbium luteum, [346].
Nests, variation in, [208], [228], [234].
Neuter insects, [230], [231].
New Zealand, productions of, not perfect, [163].
—, naturalised products of, [309].
—, fossil birds of, [310].
—, glaciers of, [335].
—, crustaceans of, [338].
—, algæ of, [338].
—, flora of, [354].
—, number of plants of, [374].
Newman, Col., on humble-bees, [57].
Newton, Prof., on earth attached to a partridge’s foot, [328].
Newton, Sir I., attacked for irreligion, [421].
Nicotiana, crossed varieties of, [258].
—, certain species very sterile, [243].
Nitsche, Dr., on the Polyzoa, [193].
Noble, Mr., on fertility of Rhododendron, [239].
Nodules, phosphatic, in azoic rocks, [287].
Oaks, variability of, [40].
Œnonis, small imperfect flowers of, [173].
Onites apelles, [108].
Orchids, fertilisation of, [154].
—, the development of their flowers, [195].
—, forms of, [372].
Orchis, pollen of, [151].
Organisation, tendency to advance, [97].
Organs of extreme perfection, [143].
—, electric, of fishes, [150].
—, of little importance, [156].
—, homologous, [382].
—, rudiments of, and nascent, [397].
Ornithorhynchus, [83], [367].
—, mammæ of, [190].
Ostrich not capable of flight, [180].
—, habit of laying eggs together, [215].
—, American, two species of, [318].
Otter, habits of, how acquired, [138].
Ouzel, water, [142].
Owen, Prof., on birds not flying, [108].
—, on vegetative repetition, [118].
—, on variability of unusually developed parts, [119].
—, on the eyes of fishes, [145].
—, on the swim-bladder of fishes, [148].
—, on fossil horse of La Plata, [294].
—, on generalised form, [301].
—, on relation of ruminants and pachyderms, [303].
—, on fossil birds of New Zealand, [310].
—, on succession of types, [310].
—, on affinities of the dugong, [365].
—, on homologous organs, [383].
—, on the metamorphosis of cephalopods, [390].
Pacific Ocean, faunas of, [317].
Pacini, on electric organs, [151].
Paley, on no organ formed to give pain, [163].
Pallas, on the fertility of the domesticated descendants of wild stocks, [241].
Palm with hooks, [158].
Papaver bracteatum, [174].
Paraguay, cattle destroyed by flies, [56].
Parasites, [215].
Partridge, with ball of dirt attached to foot, [328].
Parts greatly developed, variable, [119].
Parus major, [141].
Passiflora, [238].
Peaches in United States, [66].
Pear, grafts of, [246].
Pedicellariæ, [191].
Pelargonium, flowers of, [166].
—, sterility of, [239].
Peloria, [116].
Pelvis of women, [115].
Period, glacial, [330].
Petrels, habits of, [142].
Phasianus, fertility of hybrids, [240].
Pheasant, young, wild, [211].
Pictet, Prof., on groups of species suddenly appearing, [282].
—, on rate of organic change, [291].
—, on continuous succession of genera, [293].
—, on change in latest tertiary forms, [278].
—, on close alliance of fossils in consecutive formations, [306].
—, on early transitional links, [283].
Pierce, Mr., on varieties of wolves, [71].
Pigeons with feathered feet and skin between toes, [9].
—, breeds described, and origin of, [15].
—, breeds of, how produced, [28], [30].
—, tumbler, not being able to get out of egg, [68].
—, reverting to blue colour, [127].
—, instinct of tumbling, [210].
—, young of, [392].
Pigs, black, not affected by the paint-root, [9].
—, modified by want of exercise, [159].
Pistil, rudimentary, [397].
Plants, poisonous, not affecting certain coloured animals, [9].
—, selection, applied to, [27].
—, gradual improvement of, [27].
—, not improved in barbarous countries, [27].
—, dimorphic, [35], [253].
—, destroyed by insects, [53].
—, in midst of range, have to struggle with other plants, [60].
—, nectar of, [73].
—, fleshy, on sea-shores, [107].
—, climbing, [147], [196].
—, fresh-water, distribution of, [345].
—, low in scale, widely distributed, [359].
Pleuronectidæ, their structure, [186].
Plumage, laws of change in sexes of birds, [70].
Plums in the United States, [66].
Pointer dog, origin of, [25].
—, habits of, [210].
Poison not affecting certain coloured animals, [9].
Poison, similar effect of, on animals and plants, [425].
Pollen of fir-trees, [164].
—, transported by various means, [154], [161].
Pollinia, their development, [195].
Polyzoa, their avicularia, [193].
Poole, Col., on striped hemionus, [128].
Potemogeton, [346].
Pouchet, on the colours of flat-fish, [188].
Prestwich, Mr., on English and French eocene formations, [300].
Proctotrupes, [142].
Proteolepas, [118].
Proteus, [112].
Psychology, future progress of, [428].
Pyrgoma, found in the chalk, [284].
Quagga, striped, [129].
Quatrefages, M., on hybrid moths, [240].
Quercus, variability of, [40].
Quince, grafts of, [246].
Rabbit, disposition of young, [211].
Races, domestic, characters of, [12].
Race-horses, Arab, [26].
—, English, [323].
Radcliffe, Dr., the electrical organs of the torpedo, [150].
Ramond, on plants of Pyrenees, [331].
Ramsay, Prof., on subaërial denudation, [267].
—, on thickness of the British formations, [268], [269].
—, on faults, .
Ramsay, Mr., on instincts of cuckoo, [213].
Ratio of increase, [50].
Rats, supplanting each other, [59].
—, acclimatisation of, [113].
—, blind, in cave, [110].
Rattle-snake, [162].
Reason and instinct, [205].
Recapitulation, general, [404].
Reciprocity of crosses, [243].
Record, geological, imperfect, [264].
Rengger, on flies destroying cattle, [56].
Reproduction, rate of, [50].
Resemblance, protective, of insects, [181].
—, to parents in mongrels and hybrids, [260].
Reversion, law of inheritance, [11].
—, in pigeons, to blue colour, [127].
Rhododendron, sterility of, [239].
Richard, Prof., on Aspicarpa, [367].
Richardson, Sir J., on structure of squirrels, [139].
—, on fishes of the southern hemisphere, [338].
Robinia, grafts of, [246].
Rodents, blind, [110].
Rogers, Prof., Map of N. America, [274].
Rudimentary organs, [397].
Rudiments important for classification, [367].
Rütimeyer, on Indian cattle, [14], [241].
Sageret, on grafts, [246].
Salamandra atra, [397].
Saliva used in nests, [228].
Salmons, males fighting, and hooked jaws of, [69].
Salt-water, how far injurious to seeds, [325].
—, not destructive to land-shells, [353].
Salter, Mr., on early death of hybrid embryos, [249].
Salvin, Mr., on the beaks of ducks, [184].
Saurophagus sulphuratus, [141].
Schacht, Prof., on Phyllotaxy, [173].
Schiödte, on blind insects, [110].
—, on flat-fish, [186].
Schlegel, on snakes, [115].
Schöbl, Dr., on the ears of mice, [172].
Scott, Mr. J., on the self-sterility of orchids, [238].
—, on the crossing of varieties of verbascum, [258].
Sea-water, how far injurious to seeds, [325].
—, not destructive to land-shells, [325].
Sebright, Sir J., on crossed animals, [15].
Sedgwick, Prof., on groups of species suddenly appearing, [282].
Seedlings destroyed by insects, [53].
Seeds, nutriment in, [60].
—, winged, [117].
—, means of dissemination, [154], [161], [327], [328].
—, power of resisting salt-water, [325].
—, in crops and intestines of birds, [326], [327].
—, eaten by fish, [327], [346].
—, in mud, [345].
—, hooked, on islands, [349].
Selection of domestic products, [22].
—, principle not of recent origin, [27].
—, unconscious, [27].
—, natural, [62].
—, sexual, [69].
—, objections to term, [63].
—, natural, has not induced sterility, [247].
Sexes, relations of, [69].
Sexual characters variable, [123].
—, selection, [69].
Sheep, Merino, their selection, [23].
—, two sub-breeds, unintentionally produced, [26].
—, mountain, varieties of, [59].
Shells, colours of, [107].
—, hinges of, [154].
—, littoral, seldom embedded, [270].
—, fresh-water, long retain the same forms, [308].
—, fresh-water, dispersal of, [344].
—, of Madeira, [349].
—, land, distribution of, [349].
—, land, resisting salt water, [325].
Shrew-mouse, [373].
Silene, infertility of crosses, [243].
Silliman, Prof., on blind rat, [110].
Sirenia, their affinities, [302].
Sitaris, metamorphosis of, [394].
Skulls of young mammals, [159], [384].
Slave-making instinct, [216].
Smith, Col. Hamilton, on striped horses, [129].
Smith, Dr., on the Polyzoa, [193].
Smith, Mr. Fred., on slave-making ants, [217].
—, on neuter ants, [231].
Snake with tooth for cutting through egg-shell, [214].
Somerville, Lord, on selection of sheep, [23].
Sorbus, grafts of, [246].
Sorex, [373].
Spaniel, King Charles’ breed, [25].
Specialisation of organs, [98].
Species, polymorphic, [35].
—, dominant, [43].
—, common, variable, [42].
—, in large genera variable, [44].
—, groups of, suddenly appearing, [282], [285].
—, beneath Silurian formations, [287].
—, successively appearing, [290].
—, changing simultaneously throughout the world, [297].
Spencer, Lord, on increase in size of cattle, [26].
Spencer, Mr. Herbert, on the first steps in differentiation, [100].
—, on the tendency to an equilibrium in all forces, [252].
Sphex, parasitic, [216].
Spiders, development of, [390].
Sports in plants, [8].
Sprengel, C.C., on crossing, [76].
—, on ray-florets, [116].
Squalodon, [302].
Squirrels, gradations in structure, [139].
Staffordshire, heath, changes in, [55].
Stag-beetles, fighting, [69].
Star fishes, eyes of, [144].
—, their pedicellariæ, [192].
Sterility from changed conditions of life, [7].
—, of hybrids, [236].
—, laws of, [241].
—, causes of, [247].
—, from unfavourable conditions, [250].
—, not induced through natural selection, [247].
St. Helena, productions of, [347].
St. Hilaire, Aug., on variability of certain plants, [174].
—, on classification, [368].
St. John, Mr., on habits of cats, [209].
Sting of bee, [163].
Stocks, aboriginal, of domestic animals, [14].
Strata, thickness of, in Britain, [268], [269].
Stripes on horses, [128].
Structure, degrees of utility of, [159].
Struggle for existence, [48].
Succession, geological, [290].
—, of types in same areas, [310].
Swallow, one species supplanting another, [59].
Swaysland, Mr., on earth adhering to the feet of migratory birds, [328].
Swifts, nests of, [228].
Swim-bladder, [148].
Switzerland, lake habitations of, [13].
System, natural, [364].
Tail of giraffe, [157].
—, of aquatic animals, [157].
—, prehensile, [188].
—, rudimentary, [400].
Tanais, dimorphic, [36].
Tarsi deficient, [108].
Tausch, Dr., on umbelliferæ, [173].
Teeth and hair correlated, [115].
—, rudimentary, in embryonic calf, [397], [420].
Tegetmeier, Mr., on cells of bees, [222], [226].
Temminck, on distribution aiding classification, [369].
Tendrils, their development, [196].
Thompson, Sir W., on the age of the habitable world, [286].
—, on the consolidation of the crust of the earth, [409].
Thouin, on grafts, [246].
Thrush, aquatic species of, [142].
—, mocking, of the Galapagos, [356].
—, young of, spotted, [388].
—, nest of, [234].
Thuret, M., on crossed fuci, [243].
Thwaites, Mr., on acclimatisation, [112].
Thylacinus, [374].
Tierra del Fuego, dogs of, [211].
—, plants of, [341].
Timber-drift, [326].
Time, lapse of, [266].
—, by itself not causing modification, [81].
Titmouse, [141].
Toads on islands, [350].
Tobacco, crossed varieties of, [258].
Tomes, Mr., on the distribution of bats, [351].
Transitions in varieties rare, [134].
Traquair, Dr., on flat-fish, [188].
Trautschold, on intermediate varieties, [275].
Trees on islands belong to peculiar orders, [350].
—, with separated sexes, [78].
Trifolium pratense, [57], [75].
—, incarnatum, [75].
Trigonia, [296].
Trilobites, [286].
—, sudden extinction of, [297].
Trimen, Mr., on imitating-insects, [377].
Trimorphism in plants, [35], [252].
Troglodytes, [234].
Tuco-tuco, blind, [110].
Tumbler pigeons, habits of, hereditary, [210].
—, young of, [392].
Turkey-cock, tuft of hair on breast, [70].
—, naked skin on head, [158].
—, young of, instinctively wild, [265].
Turnip and cabbage, analogous variations of, [125].
Type, unity of, [166], [167].
Types, succession of, in same areas, [310].
Typotherium, [302].
Udders enlarged by use, [8].
—, rudimentary, [397].
Ulex, young leaves of, [388].
Umbelliferæ, flowers and seeds of, [116].
—, outer and inner florets of, [173].
Unity of type, [166], [167].
Uria lacrymans, [72].
Use, effects of, under domestication, [8].
—, effects of, in a state of nature, [108].
Utility, how far important in the construction of each part, [159].
Valenciennes, on fresh-water fish, [344].
Variability of mongrels and hybrids, [259].
Variation, under domestication, [5].
—, caused by reproductive system being affected by conditions of life, [7].
—, under nature, [33].
—, laws of, [106].
—, correlated, [9], [114], [159].
Variations appear at corresponding ages, [10], [67].
—, analogous in distinct species, [124].
Varieties, natural, [32].
—, struggle between, [59].
—, domestic, extinction of, [86].
—, transitional, rarity of, [134].
—, when crossed, fertile, [257].
—, when crossed, sterile, [256].
—, classification of, [371].
Verbascum, sterility of, [238].
—, varieties of, crossed, [258].
Verlot, M., on double stocks, [230].
Verneuil, M. de, on the succession of species, [299].
Vibracula of the Polyzoa, [193].
Viola, small imperfect flowers of, [173].
—, tricolor, [57].
Virchow, on the structure of the crystalline lens, [145].
Virginia, pigs of, [66].
Volcanic islands, denudation of, [268].
Vulture, naked skin on head, [158].
Wading-birds, [375].
Wagner, Dr., on Cecidomyia, [387].
Wagner, Moritz, on the importance of isolation, [81].
Wallace, Mr., on origin of species, [1].
—, on the limit of variation under domestication, [31].
—, on dimorphic lepidoptera, [36], [232].
—, on races in the Malay Archipelago, [37].
—, on the improvement of the eye, [145].
—, on the walking-stick insect, [182].
—, on laws of geographical distribution, [322].
—, on the Malay Archipelago, [351].
—, on mimetic animals, [377].
Walsh, Mr. B.D., on phytophagic forms, [38].
—, on equal variability, [125].
Water, fresh, productions of, [343].
Water-hen, [143].
Waterhouse, Mr., on Australian marsupials, [90].
—, on greatly developed parts being variable, [119].
—, on the cells of bees, [220].
—, on general affinities, [379].
Water-ouzel, [142].
Watson, Mr. H.C., on range of varieties of British plants, [37], [46].
—, on acclimatisation, [112].
—, on flora of Azores, [328].
—, on rarity of intermediate varieties, [136].
—, on Alpine plants, [331].
—, on convergence, [100].
—, on the indefinite multiplication of species, [101].
Weale, Mr., on locusts transporting seeds, [327].
Web of feet in water-birds, [142].
Weismann, Prof., on the causes of variability, [6].
—, on rudimentary organs, [400].
West Indian islands, mammals of, [352].
Westwood, on species in large genera being closely allied to others, [45].
—, on the tarsi of Engidæ, [124].
—, on the antennæ of hymenopterous insects, [366].
Whales, [182].
Wheat, varieties of, [88].
White Mountains, flora of, [330].
Whittaker, Mr., on lines of escarpment, [267].
Wichura, Max, on hybrids, [249], [251], [260].
Wings, reduction of size, [109].
—, of insects homologous with branchiæ, [148].
—, rudimentary, in insects, [397].
Wolf crossed with dog, [210].
—, of Falkland Isles, [351].
Wollaston, Mr., on varieties of insects, [38].
—, on fossil varieties of shells in Madeira, [42].
—, on colours of insects on sea-shore, [107].
—, on wingless beetles, [109].
—, on rarity of intermediate varieties, [136].
—, on insular insects, [347].
—, on land-shells of Madeira naturalised, [357].
Wolves, varieties of, [71].
Woodcock with earth attached to leg, [328].
Woodpecker, habits of, [141].
—, green colour of, [158].
Woodward, Mr., on the duration of specific forms, [276].
—, on Pyrgoma, [284].
—, on the continuous succession of genera, [293].
—, on the succession of types, [311].
World, species changing simultaneously throughout, [297].
Wrens, nest of, [234].
Wright, Mr. Chauncey, on the giraffe, [178].
—, on abrupt modifications, [203].
Wyman, Prof., on correlation of colour and effects of poison, [9].
—, on the cells of the bee, [22].
Youatt, Mr., on selection, [23].
—, on sub-breeds of sheep, [26].
—, on rudimentary horns in young cattle, [400].
Zanthoxylon, [174].
Zebra, stripes on, [128].
Zeuglodon, [302].