Aberrant groups

  Abyssinia, plants of

  Acclimatisation

  Adoxa

  Affinities of extinct species
 —of organic beings

  Agassiz on Amblyopsis
 —on groups of species suddenly appearing
 —on prophetic forms
 —on embryological succession
 —on the Glacial period
 —on embryological characters
 —on the latest tertiary forms
 —on parallelism of embryological development and geological succession
 —Alex., on pedicellariae

  Algae of New Zealand

  Alligators, males, fighting

  Alternate generations

  Amblyopsis, blind fish

  America, North, productions allied to those of Europe
 —boulders and glaciers of
 —South, no modern formations on west coast

  Ammonites, sudden extinction of

  Anagallis, sterility of

  Analogy of variations

  Andaman Islands inhabited by a toad

  Ancylus

  Animals, not domesticated from being variable
 —domestic; descended from several stocks
 —acclimatisation of

  Animals of Australia
 —with thicker fur in cold climates
 —blind, in caves
 —extinct, of Australia

  Anomma

  Antarctic islands, ancient flora of

  Antechinus

  Ants attending aphides
 —slave-making instinct
 —neuters, structure of

  Apes, not having acquired intellectual powers

  Aphides attended by ants

  Aphis, development of

  Apteryx

  Arab horses

  Aralo-Caspian Sea

  Archeopteryx

  Archiac, M. de, on the succession of species

  Artichoke, Jerusalem

  Ascension, plants of

  Asclepias, pollen of

  Asparagus

  Aspicarpa

  Asses, striped
 —improved by selection

  Ateuchus

  Aucapitaine, on land-shells

  Audubon, on habits of frigate-bird
 —on variation in birds' nests
 —on heron eating seeds

  Australia, animals of
 —dogs of
 —extinct animals of
 —European plants in
 —glaciers of

  Azara, on flies destroying cattle

  Azores, flora of

  Babington, Mr., on British plants

  Baer, Von, standard of Highness
 —comparison of bee and fish
 —embryonic similarity of the Vertebrata

  Baker, Sir S., on the giraffe

  Balancement of growth

  Baleen

  Barberry, flowers of

  Barrande, M., on Silurian colonies
 —on the succession of species
 —on parallelism of palaeozoic formations
 —on affinities of ancient species

  Barriers, importance of

  Bates, Mr., on mimetic butterflies

  Batrachians on islands

  Bats, how structure acquired
 —distribution of

  Bear, catching water-insects

  Beauty, how acquired

  Bee, sting of
 —queen, killing rivals
 —Australian, extermination of

  Bees, fertilizing flowers
 —hive, not sucking the red clover
 —hive, cell-making instinct
 —Ligurian
 —variation in habits

  Bees, parasitic
 —humble, cells of

  Beetles, wingless, in Madeira
 —with deficient tarsi

  Bentham, Mr., on British plants
 —on classification

  Berkeley, Mr., on seeds in salt-water

  Bermuda, birds of

  Birds acquiring fear
 —beauty of
 —annually cross the Atlantic
 —colour of, on continents
 —footsteps, and remains of, in secondary rocks
 —fossil, in caves of Brazil
 —of Madeira, Bermuda, and Galapagos
 —song of males
 —transporting seeds
 —waders
 —wingless

  Bizcacha, affinities of

  Bladder for swimming, in fish

  Blindness of cave animals

  Blyth, Mr., on distinctness of Indian cattle
 —on striped Hemionus
 —on crossed geese

  Borrow, Mr., on the Spanish pointer

  Bory St. Vincent, on Batrachians

  Bosquet, M., on fossil Chthamalus

  Boulders, erratic, on the Azores

  Branchiae
 —of crustaceans

  Braun, Prof., on the seeds of Fumariaceae

  Brent, Mr., on house-tumblers

  Britain, mammals of

  Broca, Prof., on Natural Selection

  Bronn, Prof., on duration of specific forms
 —various objections by

  Brown, Robert, on classification

  Brown-Sequard, on inherited mutilations

  Busk, Mr., on the Polyzoa

  Butterflies, mimetic

  Buzareingues, on sterility of varieties

  Cabbage, varieties of, crossed

  Calceolaria

  Canary-birds, sterility of hybrids

  Cape de Verde Islands, productions of
 —plants of, on mountains

  Cape of Good Hope, plants of

  Carpenter, Dr., on foraminifera

  Carthemus

  Catasetum

  Cats, with blue eyes, deaf
 —variation in habits of
 —curling tail when going to spring

  Cattle destroying fir-trees
 —destroyed by flies in Paraguay
 —breeds of, locally extinct
 —fertility of Indian and European breeds
 —Indian

  Cave, inhabitants of, blind

  Cecidomyia

  Celts, proving antiquity of man

  Centres of creation

  Cephalopodae, structures of eyes
 —development of

  Cercopithecus, tail of

  Ceroxylus laceratus

  Cervulus

  Cetacea, teeth and hair
 —development of the whalebone

  Cetaceans

  Ceylon, plants of

  Chalk formation

  Characters, divergence of
 —sexual, variable
 —adaptive or analogical

  Charlock

  Checks to increase
 —mutual

  Chelae of Crustaceans

  Chickens, instinctive tameness of

  Chironomus, its asexual reproduction

  Chthamalinae

  Chthamalus, cretacean species of

  Circumstances favourable to selection of domestic products
 —to natural selection

  Cirripedes capable of crossing
 —carapace aborted
 —their ovigerous frena
 —fossil
 —larvae of

  Claparede, Prof., on the hair-claspers of the Acaridae

  Clarke, Rev. W.B., on old glaciers in Australia

  Classification

  Clift, Mr., on the succession of types

  Climate, effects of, in checking increase of beings
 —adaptation of, to organisms

  Climbing plants
 —development of

  Clover visited by bees

  Cobites, intestine of

  Cockroach

  Collections, palaeontological, poor

  Colour, influenced by climate
 —in relation to attacks by flies

  Columba livia, parent of domestic pigeons

  Colymbetes

  Compensation of growth

  Compositae, flowers and seeds of
 —outer and inner florets of
 —male flowers of

  Conclusion, general

  Conditions, slight changes in, favourable to fertility

  Convergence of genera

  Coot

  Cope, Prof., on the acceleration or retardation of the period of reproduction

  Coral-islands, seeds drifted to
 —reefs, indicating movements of earth

  Corn-crake

  Correlated variation in domestic productions

  Coryanthes

  Creation, single centres of

  Crinum

  Croll, Mr., on subaerial denudation
 —on the age of our oldest formations
 —on alternate Glacial periods in the North and South

  Crosses, reciprocal

  Crossing of domestic animals, importance in altering breeds
 —advantages of
 —unfavourable to selection

  Cruger, Dr., on Coryanthes

  Crustacea of New Zealand

  Crustacean, blind air-breathers

  Crustaceans, their chelae

  Cryptocerus

  Ctenomys, blind

  Cuckoo, instinct of

  Cunningham, Mr., on the flight of the logger-headed duck

  Currants, grafts of

  Currents of sea, rate of

  Cuvier on conditions of existence
 —on fossil monkeys

  Cuvier, Fred., on instinct

  Cyclostoma, resisting salt water

  Dana, Prof., on blind cave-animals
 —on relations of crustaceans of Japan
 —on crustaceans of New Zealand

  Dawson, Dr., on eozoon

  De Candolle, Aug. Pyr., on struggle for existence
 —on umbelliferae
 —on general affinities

  De Candolle, Alph., on the variability of oaks
 —on low plants, widely dispersed
 —on widely-ranging plants being variable
 —on naturalisation
 —on winged seeds
 —on Alpine species suddenly becoming rare
 —on distribution of plants with large seeds
 —on vegetation of Australia
 —on fresh-water plants
 —on insular plants

  Degradation of rocks

  Denudation, rate of
 —of oldest rocks
 —of granite areas

  Development of ancient forms

  Devonian system

  Dianthus, fertility of crosses

  Dimorphism in plants

  Dirt on feet of birds

  Dispersal, means of
 —during Glacial period

  Distribution, geographical
 —means of

  Disuse, effect of, under nature

  Diversification of means for same general purpose

  Division, physiological, of labour

  Divergence of character

  Dog, resemblance of jaw to that of the Thylacinus

  Dogs, hairless, with imperfect teeth
 —descended from several wild stocks
 —domestic instincts of
 —inherited civilisation of
 —fertility of breeds together
 —of crosses
 —proportions of body in different breeds, when young

  Domestication, variation under

  Double flowers

  Downing, Mr., on fruit-trees in America

  Dragon-flies, intestines of

  Drift-timber

  Driver-ant

  Drones killed by other bees

  Duck, domestic, wings of, reduced
 —beak of
 —logger-headed

  Duckweed

  Dugong, affinities of

  Dung-beetles with deficient tarsi

  Dyticus

  Earl, Mr., W., on the Malay Archipelago

  Ears, drooping, in domestic animals
 —rudimentary

  Earth, seeds in roots of trees
 —charged with seeds

  Echinodermata, their pedicellariae

  Eciton

  Economy of organisation

  Edentata, teeth and hair
 —fossil species of

  Edwards, Milne, on physiological division of labour
 —on gradations of structure

  Edwards, on embryological characters

  Eggs, young birds escaping from

  Egypt, productions of, not modified

  Electric organs

  Elephant, rate of increase
 —of Glacial period

  Embryology

  Eozoon Canadense

  Epilipsy inherited

  Existence, struggle for
 —condition of

  Extinction, as bearing on natural selection
 —of domestic varieties

  Eye, structure of
 —correction for aberration

  Eyes, reduced, in moles

  Fabre, M., on hymenoptera fighting
 —on parasitic sphex
 —on Sitaris

  Falconer, Dr., on naturalisation of plants in India
 —on elephants and mastodons
 —and Cautley on mammals of sub-Himalayan beds

  Falkland Islands, wolf of

  Faults

  Faunas, marine

  Fear, instinctive, in birds

  Feet of birds, young molluscs adhering to

  Fertilisation variously effected

  Fertility of hybrids
 —from slight changes in conditions
 —of crossed varieties

  Fir-trees destroyed by cattle
 —pollen of

  Fish, flying
 —teleostean, sudden appearance of
 —eating seeds
 —fresh-water, distribution of

  Fishes, ganoid, now confined to fresh water
 —ganoid, living in fresh water
 —electric organs of
 —of southern hemisphere

  Flight, powers of, how acquired

  Flint-tools, proving antiquity of man

  Flower, Prof., on the larynx
 —on Halitherium
 —on the resemblance between the jaws of the dog and Thylacinus
 —on the homology of the feet of certain marsupials

  Flowers, structure of
 —in relation to crossing
 —of composite and umbelliferae
 —beauty of
 —double

  Flysch formation, destitute of organic remains

  Forbes, Mr. D., on glacial action in the Andes

  Forbes, E., on colours of shells
 —on abrupt range of shells in depth
 —on poorness of palaeontological collections
 —on continuous succession of genera
 —on continental extensions
 —on distribution during Glacial period
 —on parallelism in time and space

  Forests, changes in, in America

  Formation, Devonian
 —Cambrian
 —intermittent
 —thickness of, in Britain

  Formica
 —rufescens
 —sanguinea
 —flava, neuter of

  Forms, lowly organised, long enduring

  Frena, ovigerous, of cirripedes

  Fresh-water productions, dispersal of

  Fries on species in large genera being closely allied to other species

  Frigate-bird

  Frogs on islands

  Fruit-trees, gradual improvement of
 —in United States
 —varieties of, acclimatised in United States

  Fuci, crossed

  Fur, thicker in cold climates

  Furze

  Galapagos Archipelago, birds of
 —productions of

  Galaxias, its wide range

  Galeopithecus

  Game, increase of, checked by vermin

  Gartner on sterility of hybrids
 —on reciprocal crosses
 —on crossed maize and verbascum
 —on comparison of hybrids and mongrels

  Gaudry, Prof., on intermediate genera of fossil mammals in Attica

  Geese, fertility when crossed
 —upland

  Geikie, Mr., on subaerial denudation

  Genealogy, important in classification

  Generations, alternate

  Geoffroy St. Hilaire, on balancement
 —on homologous organs

  Geoffroy St. Hilaire, Isidore, on variability of repeated parts
 —on correlation, in monstrosities
 —on correlation
 —on variable parts being often monstrous

  Geographical distribution

  Geography, ancient

  Geology, future progress of
 —imperfection of the record

  Gervais, Prof., on Typotherium

  Giraffe, tail of
 —structure of

  Glacial period
 —affecting the North and South

  Glands, mammary

  Gmelin, on distribution

  Godwin-Austin, Mr., on the Malay Archipelago

  Goethe, on compensation of growth

  Gomphia

  Gooseberry, grafts of

  Gould, Dr. Aug. A., on land-shells

  Gould, Mr., on colours of birds
 —on instincts of cuckoo
 —on distribution of genera of birds

  Gourds, crossed

  Graba, on the Uria lacrymans

  Grafting, capacity of

  Granite, areas of denuded

  Grasses, varieties of

  Gray, Dr. Asa, on the variability of oaks
 —on man not causing variability
 —on sexes of the holly
 —on trees of the United States
 —on naturalised plants in the United States
 —on aestivation
 —on rarity of intermediate varieties
 —on Alpine plants

  Gray, Dr. J.E., on striped mule

  Grebe

  Grimm, on asexual reproduction

  Groups, aberrant

  Grouse, colours of
 —red, a doubtful species

  Growth, compensation of

  Gunther, Dr., on flat-fish
 —on prehensile tails
 —on the fishes of Panama
 —on the range of fresh-water fishes
 —on the limbs of Lepidosiren

  Haast, Dr., on glaciers of New Zealand

  Habit, effect of, under domestication
 —effect of, under nature
 —diversified, of same species

  Hackel, Prof., on classification and the lines of descent

  Hair and teeth, correlated

  Halitherium

  Harcourt, Mr. E.V., on the birds of Madeira

  Hartung, M., on boulders in the Azores

  Hazel-nuts

  Hearne, on habits of bears

  Heath, changes in vegetation

  Hector, Dr., on glaciers of New Zealand

  Heer, Oswald, on ancient cultivated plants
 —on plants of Madeira

  Helianthemum

  Helix pomatia, resisting salt water

  Helmholtz, M., on the imperfection of the human eye

  Helosciadium

  Hemionus, striped

  Hensen, Dr., on the eyes of Cephalopods

  Herbert, W., on struggle for existence
 —on sterility of hybrids

  Hermaphrodites crossing

  Heron eating seed

  Heron, Sir R., on peacocks

  Heusinger, on white animals poisoned by certain plants

  Hewitt, Mr., on sterility of first crosses

  Hildebrand, Prof., on the self-sterility of Corydalis

  Hilgendorf, on intermediate varieties

  Himalaya, glaciers of
 —plants of

  Hippeastrum

  Hippocampus

  Hofmeister, Prof., on the movements of plants

  Holly-trees, sexes of

  Hooker, Dr., on trees of New Zealand
 —on acclimatisation of Himalayan trees
 —on flowers of umbelliferae
 —on the position of ovules
 —on glaciers of Himalaya
 —on algae of New Zealand
 —on vegetation at the base of the Himalaya
 —on plants of Tierra del Fuego
 —on Australian plants
 —on relations of flora of America
 —on flora of the Antarctic lands
 —on the plants of the Galapagos
 —on glaciers of the Lebanon
 —on man not causing variability
 —on plants of mountains of Fernando Po

  Hooks on palms
 —on seeds, on islands

  Hopkins, Mr., on denudation

  Hornbill, remarkable instinct of

  Horns, rudimentary

  Horse, fossil in La Plata
 —proportions of, when young

  Horses destroyed by flies in Paraguay
 —striped

  Horticulturists, selection applied by

  Huber on cells of bees

  Huber, P., on reason blended with instinct
 —on habitual nature of instincts
 —on slave-making ants
 —on Melipona domestica

  Hudson, Mr., on the Ground-woodpecker of La Plata
 —on the Molothrus

  Humble-bees, cells of

  Hunter, J., on secondary sexual characters

  Hutton, Captain, on crossed geese

  Huxley, Prof., on structure of hermaphrodites
 —on the affinities of the Sirenia
 —on forms connecting birds and reptiles
 —on homologous organs
 —on the development of aphis

  Hybrids and mongrels compared

  Hybridism

  Hydra, structure of

  Hymenoptera, fighting

  Hymenopterous insect, diving

  Hyoseris

  Ibla

  Icebergs transporting seeds

  Increase, rate of

  Individuals, numbers favourable to selection
 —many, whether simultaneously created

  Inheritance, laws of
 —at corresponding ages

  Insects, colour of, fitted for their stations
 —sea-side, colours of
 —blind, in caves
 —luminous
 —their resemblance to certain objects
 —neuter

  Instinct, not varying simultaneously with structure

  Instincts, domestic

  Intercrossing, advantages of

  Islands, oceanic

  Isolation favourable to selection

  Japan, productions of

  Java, plants of

  Jones, Mr. J.M., on the birds of Bermuda

  Jordain, M., on the eye-spots of star fishes

  Jukes, Prof., on subaerial denudation

  Jussieu on classification

  Kentucky, caves of

  Kerguelen-land, flora of

  Kidney-bean, acclimatisation of

  Kidneys of birds

  Kirby, on tarsi deficient in beetles

  Knight, Andrew, on cause of variation

  Kolreuter, on intercrossing
 —on the barberry
 —on sterility of hybrids
 —on reciprocal crosses
 —on crossed varieties of nicotiana
 —on crossing male and hermaphrodite flowers

  Lamarck, on adaptive characters

  Lancelet, eyes of

  Landois, on the development of the wings of insects

  Land-shells, distribution of
 —of Madeira, naturalised
 —resisting salt water

  Languages, classification of

  Lankester, Mr. E. Ray, on longevity
 —on homologies

  Lapse, great, of time

  Larvae

  Laurel, nectar secreted by the leaves

  Laurentian formation

  Laws of variation

  Leech, varieties of

  Leguminosae, nectar secreted by glands

  Leibnitz, attack on Newton

  Lepidosiren, limbs in a nascent condition

  Lewes, Mr. G.H., on species not having changed in Egypt
 —on the Salamandra atra
 —on many forms of life having been at first evolved

  Life, struggle for

  Lingula, Silurian

  Linnaeus, aphorism of

  Lion, mane of
 —young of, striped

  Lobelia fulgens

  Lobelia, sterility of crosses

  Lockwood, Mr., on the ova of the Hippocampus

  Locusts transporting seeds

  Logan, Sir W., on Laurentian formation

  Lowe, Rev. R.T., on locusts visiting Madeira

  Lowness, of structure connected with variability
 —related to wide distribution

  Lubbock, Sir J., on the nerves of coccus
 —on secondary sexual characters
 —on a diving hymenopterous insect
 —on affinities
 —on metamorphoses

  Lucas, Dr. P., on inheritance
 —on resemblance of child to parent

  Lund and Clausen, on fossils of Brazil

  Lyell, Sir C., on the struggle for existence
 —on modern changes of the earth
 —on terrestrial animals not having been developed on islands
 —on a carboniferous land-shell
 —on strata beneath Silurian system
 —on the imperfection of the geological record
 —on the appearance of species
 —on Barrande's colonies
 —on tertiary formations of Europe and North America
 —on parallelism of tertiary formations
 —on transport of seeds by icebergs
 —on great alternations of climate
 —on the distribution of fresh-water shells
 —on land-shells of Madeira

  Lyell and Dawson, on fossilized trees in Nova Scotia

  Lythrum salicaria, trimorphic

  Macleay, on analogical characters

  Macrauchenia

  McDonnell, Dr., on electric organs

  Madeira, plants of
 —beetles of, wingless
 —fossil land-shells of
 —birds of

  Magpie tame in Norway

  Males, fighting

  Maize, crossed

  Malay Archipelago, compared with Europe
 —mammals of

  Malm, on flat-fish

  Malpighiaceae, small imperfect flowers of

  Mammae, their development
 —rudimentary

  Mammals, fossil, in secondary formation
 —insular

  Man, origin of

  Manatee, rudimentary nails of

  Marsupials, fossil species of

  Marsupials of Australia, structure of their feet

  Martens, M., experiment on seeds

  Martin, Mr. W.C., on striped mules

  Masters, Dr., on Saponaria

  Matteucci, on the electric organs of rays

  Matthiola, reciprocal crosses of

  Maurandia

  Means of dispersal

  Melipona domestica

  Merrill, Dr., on the American cuckoo

  Metamorphism of oldest rocks

  Mice destroying bees
 —acclimatisation of
 —tails of

  Miller, Prof., on the cells of bees

  Mirabilis, crosses of

  Missel-thrush

  Mistletoe, complex relations of

  Mivart, Mr., on the relation of hair and teeth
 —on the eyes of cephalopods
 —various objections to Natural Selection
 —on abrupt modifications
 —on the resemblance of the mouse and antechinus

  Mocking-thrush of the Galapagos

  Modification of species, not abrupt

  Moles, blind

  Molothrus, habits of

  Mongrels, fertility and sterility of
 —and hybrids compared

  Monkeys, fossil

  Monachanthus

  Mons, Van, on the origin of fruit-trees

  Monstrosities

  Moquin-Tandon, on sea-side plants

  Morphology

  Morren, on the leaves of Oxalis

  Moths, hybrid

  Mozart, musical powers of

  Mud, seeds in

  Mules, striped

  Muller, Adolph, on the instincts of the cuckoo

  Muller, Dr. Ferdinand, on Alpine Australian plants

  Muller, Fritz, on dimorphic crustaceans
 —on the lancelet
 —on air-breathing crustaceans
 —on the self-sterility of orchids
 —on embryology in relation to classification
 —on the metamorphoses of crustaceans
 —on terrestrial and fresh-water organisms not undergoing any metamorphosis
 —on climbing plants

  Multiplication of species not indefinite

  Murchison, Sir, R., on the formations of Russia
 —on azoic formations
 —on extinction

  Murie, Dr., on the modification of the skull in old age

  Murray, Mr. A., on cave-insects

  Mustela vison

  Myanthus

  Myrmecocystus

  Myrmica, eyes of

  Nageli, on morphological characters

  Nails, rudimentary

  Nathusius, Von, on pigs

  Natural history, future progress of
 —selection
 —system

  Naturalisation of forms distinct from the indigenous species
 —in New Zealand

  Naudin, on analagous variations in gourds
 —on hybrid gourds
 —on reversion

  Nautilus, Silurian

  Nectar of plants

  Nectaries, how formed

  Nelumbium luteum

  Nests, variation in

  Neuter insects

  New Zealand, productions of, not perfect
 —naturalised products of
 —fossil birds of
 —glaciers of
 —crustaceans of
 —algae of
 —number of plants of
 —flora of

  Newman, Col., on humble-bees

  Newton, Prof., on earth attached to a partridge's foot

  Newton, Sir I., attacked for irreligion

  Nicotiana, crossed varieties of
 —certain species very sterile

  Nitsche, Dr., on the Polyzoa

  Noble, Mr., on fertility of Rhododendron

  Nodules, phosphatic, in azoic rocks

  Oak, varieties of

  Onites apelles

  Orchids, fertilisation of
 —the development of their flowers
 —forms of

  Orchis, pollen of

  Organisation, tendency to advance

  Organs of extreme perfection
 —electric, of fishes
 —of little importance
 —homologous
 —rudiments of, and nascent

  Ornithorhynchus, mammae of

  Ostrich not capable of flight
 —habit of laying eggs together
 —American, two species of

  Otter, habits of, how acquired

  Ouzel, water

  Owen, Prof., on birds not flying
 —on vegetative repetition
 —on variability of unusually developed parts
 —on the eyes of fishes
 —on the swim-bladder of fishes
 —on fossil horse of La Plata
 —on generalised form
 —on relation of ruminants and pachyderms
 —on fossil birds of New Zealand
 —on succession of types
 —on affinities of the dugong
 —on homologous organs
 —on the metamorphosis of cephalopods

  Pacific Ocean, faunas of

  Pacini, on electric organs

  Paley, on no organ formed to give pain

  Pallas, on the fertility of the domesticated descendants of wild stocks

  Palm with hooks

  Papaver bracteatum

  Paraguay, cattle destroyed by flies

  Parasites

  Partridge, with ball of dirt attached to foot

  Parts greatly developed, variable

  Parus major

  Passiflora

  Peaches in United States

  Pear, grafts of

  Pedicellariae

  Pelargonium, flowers of
 —sterility of

  Peloria

  Pelvis of women

  Period, glacial

  Petrels, habits of

  Phasianus, fertility of hybrids

  Pheasant, young, wild

  Pictet, Prof., on groups of species suddenly appearing
 —on rate of organic change
 —on continuous succession of genera
 —on close alliance of fossils in consecutive formations
 —on change in latest tertiary forms
 —on early transitional links

  Pierce, Mr., on varieties of wolves

  Pigeons with feathered feet and skin between toes
 —breeds described, and origin of
 —breeds of, how produced
 —tumbler, not being able to get out of egg
 —reverting to blue colour
 —instinct of tumbling
 —young of

  Pigs, black, not affected by the paint-root
 —modified by want of exercise

  Pistil, rudimentary

  Plants, poisonous, not affecting certain coloured animals
 —selection, applied to
 —gradual improvement of
 —not improved in barbarous countries
 —dimorphic
 —destroyed by insects
 —in midst of range, have to struggle with other plants
 —nectar of
 —fleshy, on sea-shores
 —climbing
 —fresh-water, distribution of
 —low in scale, widely distributed

  Pleuronectidae, their structure

  Plumage, laws of change in sexes of birds

  Plums in the United States

  Pointer dog, origin of
 —habits of

  Poison not affecting certain coloured animals

  Poison, similar effect of, on animals and plants

  Pollen of fir-trees
 —transported by various means

  Pollinia, their development

  Polyzoa, their avicularia

  Poole, Col., on striped hemionus

  Potemogeton

  Pouchet, on the colours of flat-fish

  Prestwich, Mr., on English and French eocene formations

  Proctotrupes

  Proteolepas

  Proteus

  Psychology, future progress of

  Pyrgoma, found in the chalk

  Quagga, striped

  Quatrefages, M., on hybrid moths

  Quercus, variability of

  Quince, grafts of

  Rabbits, disposition of young

  Races, domestic, characters of

  Race-horses, Arab
 —English

  Radcliffe, Dr., the electrical organs of the torpedo

  Ramond, on plants of Pyrenees

  Ramsay, Prof., on subaerial denudation
 —on thickness of the British formations
 —on faults

  Ramsay, Mr., on instincts of cuckoo

  Ratio of increase

  Rats, supplanting each other
 —acclimatisation of
 —blind, in cave

  Rattle-snake

  Reason and instinct

  Recapitulation, general

  Reciprocity of crosses

  Record, geological, imperfect

  Rengger, on flies destroying cattle

  Reproduction, rate of

  Resemblance, protective, of insects
 —to parents in mongrels and hybrids

  Reversion, law of inheritance
 —in pigeons, to blue colour

  Rhododendron, sterility of

  Richard, Prof., on Aspicarpa

  Richardson, Sir J., on structure of squirrels
 —on fishes of the southern hemisphere

  Robinia, grafts of

  Rodents, blind

  Rogers, Prof., Map of N. America

  Rudimentary organs

  Rudiments important for classification

  Rutimeyer, on Indian cattle

  Sageret, on grafts

  Salamandra atra

  Saliva used in nests

  Salmons, males fighting, and hooked jaws of

  Salt-water, how far injurious to seeds
 —not destructive to land-shells

  Salter, Mr., on early death of hybrid embryos

  Salvin, Mr., on the beaks of ducks

  Saurophagus sulphuratus

  Schacht, Prof., on Phyllotaxy

  Schiodte, on blind insects
 —on flat-fish

  Schlegel, on snakes

  Schobl, Dr., on the ears of mice

  Scott, Mr. J., on the self-sterility of orchids
 —on the crossing of varieties of verbascum

  Sea-water, how far injurious to seeds
 —not destructive to land-shells

  Sebright, Sir J., on crossed animals

  Sedgwick, Prof., on groups of species suddenly appearing

  Seedlings destroyed by insects

  Seeds, nutriment in
 —winged
 —means of dissemination
 —power of resisting salt-water
 —in crops and intestines of birds
 —eaten by fish
 —in mud
 —hooked, on islands

  Selection of domestic products
 —principle not of recent origin
 —unconscious
 —natural
 —sexual
 —objections to term
 —natural, has not induced sterility

  Sexes, relations of

  Sexual characters variable
 —selection

  Sheep, Merino, their selection
 —two sub-breeds, unintentionally produced
 —mountain, varieties of

  Shells, colours of, littoral
 —hinges of
 —seldom embedded

  Shells, fresh-water, long retain the same forms
 —fresh-water, dispersal of
 —of Madeira
 —land, distribution of
 —land, resisting salt water

  Shrew-mouse

  Silene, infertility of crosses

  Silliman, Prof., on blind rat

  Sirenia, their affinities

  Sitaris, metamorphosis of

  Skulls of young mammals

  Slave-making instinct

  Smith, Col. Hamilton, on striped horses

  Smith, Dr., on the Polyzoa

  Smith, Mr. Fred., on slave-making ants
 —on neuter ants

  Snake with tooth for cutting through egg-shell

  Somerville, Lord, on selection of sheep

  Sorbus, grafts of

  Sorex

  Spaniel, King Charles' breed

  Specialisation of organs

  Species, polymorphic
 —dominant
 —common, variable
 —in large genera variable
 —groups of, suddenly appearing
 —beneath Silurian formations
 —successively appearing
 —changing simultaneously throughout the world

  Spencer, Lord, on increase in size of cattle

  Spencer, Mr. Herbert, on the first steps in differentiation
 —on the tendency to an equilibrium in all forces

  Sphex, parasitic

  Spiders, development of

  Sports in plants

  Sprengel, C.C., on crossing
 —on ray-florets

  Squalodon

  Squirrels, gradations in structure

  Staffordshire, heath, changes in

  Stag-beetles, fighting

  Star fishes, eyes of
 —their pedicellariae

  Sterility from changed conditions of life
 —of hybrids
 —laws of
 —causes of
 —from unfavourable conditions
 —not induced through natural selection

  St. Helena, productions of

  St. Hilaire, Aug., on variability of certain plants
 —on classification

  St. John, Mr., on habits of cats

  Sting of bee

  Stocks, aboriginal, of domestic animals

  Strata, thickness of, in Britain

  Stripes on horses

  Structure, degrees of utility of

  Struggle for existence

  Succession, geological
 —of types in same areas

  Swallow, one species supplanting another

  Swaysland, Mr., on earth adhering to the feet of migratory birds

  Swifts, nests of

  Swim-bladder

  Switzerland, lake inhabitants of

  System, natural

  Tail of giraffe
 —of aquatic animals
 —prehensile
 —rudimentary

  Tanais, dimorphic

  Tarsi deficient

  Tausch, Dr., on umbelliferae

  Teeth and hair correlated
 —rudimentary, in embryonic calf

  Tegetmeier, Mr., on cells of bees

  Temminck, on distribution aiding classification

  Tendrils, their development

  Thompson, Sir W., on the age of the habitable world
 —on the consolidation of the crust of the earth

  Thouin, on grafts

  Thrush, aquatic species of
 —mocking, of the Galapagos
 —young of, spotted
 —nest of

  Thuret, M., on crossed fuci

  Thwaites, Mr., on acclimatisation

  Thylacinus

  Tierra del Fuego, dogs of
 —plants of

  Timber-drift

  Time, lapse of
 —by itself not causing modification

  Titmouse

  Toads on islands

  Tobacco, crossed varieties of

  Tomes, Mr., on the distribution of bats

  Transitions in varieties rare

  Traquair, Dr., on flat-fish

  Trautschold, on intermediate varieties

  Trees on islands belong to peculiar orders
 —with separated sexes

  Trifolium pratense
 —incarnatum

  Trigonia

  Trilobites
 —sudden extinction of

  Trimen, Mr., on imitating-insects

  Trimorphism in plants

  Troglodytes

  Tuco-tuco, blind

  Tumbler pigeons, habits of, hereditary
 —young of

  Turkey-cock, tuft of hair on breast

  Turkey, naked skin on head
 —young of, instinctively wild

  Turnip and cabbage, analogous variations of

  Type, unity of

  Types, succession of, in same areas

  Typotherium

  Udders enlarged by use
 —rudimentary

  Ulex, young leaves of

  Umbelliferae, flowers and seeds of
 —outer and inner florets of

  Unity of type

  Uria lacrymans

  Use, effects o
 —under domestication
 —in a state of nature

  Utility, how far important in the construction of each part

  Valenciennes, on fresh-water fish

  Variability of mongrels and hybrids

  Variation, under domestication
 —caused by reproductive system being affected by conditions of life
 —under nature
 —laws of
 —correlated

  Variations appear at corresponding ages
 —analogous in distinct species

  Varieties, natural
 —struggle between
 —domestic, extinction of
 —transitional, rarity of

  Varieties, when crossed
 —fertile
 —sterile
 —classification of

  Verbascum, sterility of
 —varieties of, crossed

  Verlot, M., on double stocks

  Verneuil, M. de, on the succession of species

  Vibracula of the Polyzoa

  Viola, small imperfect flowers of
 —tricolor

  Virchow, on the structure of the crystalline lens

  Virginia, pigs of

  Volcanic islands, denudation of

  Vulture, naked skin on head

  Wading-birds

  Wagner, Dr., on Cecidomyia

  Wagner, Moritz, on the importance of isolation

  Wallace, Mr., on origin of species
 —on the limit of variation under domestication
 —on dimorphic lepidoptera
 —on races in the Malay Archipelago
 —on the improvement of the eye
 —on the walking-stick insect
 —on laws of geographical distribution
 —on the Malay Archipelago
 —on mimetic animals

  Walsh, Mr. B.D., on phytophagic forms
 —on equal variability

  Water, fresh, productions of

  Water-hen

  Waterhouse, Mr., on Australian marsupials
 —on greatly developed parts being variable
 —on the cells of bees
 —on general affinities

  Water-ouzel

  Watson, Mr. H.C., on range of varieties of British plants
 —on acclimatisation
 —on flora of Azores
 —on rarity of intermediate varieties
 —on Alpine plants
 —on convergence
 —on the indefinite multiplication of species

  Weale, Mr., on locusts transporting seeds

  Web of feet in water-birds

  Weismann, Prof., on the causes of variability
 —on rudimentary organs

  West Indian islands, mammals of

  Westwood, on species in large genera being closely allied to others
 —on the tarsi of Engidae
 —on the antennae of hymenopterous insects

  Whales

  Wheat, varieties of

  White Mountains, flora of

  Whittaker, Mr., on lines of escarpment

  Wichura, Max, on hybrids

  Wings, reduction of size
 —of insects homologous with branchiae
 —rudimentary, in insects

  Wolf crossed with dog
 —of Falkland Isles

  Wollaston, Mr., on varieties of insects
 —on fossil varieties of shells in Madeira

  Wollaston, Mr., on colours of insects on sea-shore
 —on wingless beetles
 —on rarity of intermediate varieties
 —on insular insects
 —on land-shells of Madeira naturalised

  Wolves, varieties of

  Woodcock with earth attached to leg

  Woodpecker, habits of
 —green colour of

  Woodward, Mr., on the duration of specific forms
 —on Pyrgoma
 —on the continuous succession of genera
 —on the succession of types

  World, species changing simultaneously throughout

  Wright, Mr. Chauncey, on the giraffe
 —on abrupt modifications

  Wrens, nest of

  Wyman, Prof., on correlation of colour and effects of poison
 —on the cells of the bee

  Youatt, Mr., on selection
 —on sub-breeds of sheep
 —on rudimentary horns in young cattle

  Zanthoxylon

  Zebra, stripes on

  Zeuglodons