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Charles Darwin: The origin of species

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(I am indebted to the kindness of Mr. W.S. Dallas for this Glossary, which has been given because several readers have complained to me that some of the terms used were unintelligible to them. Mr. Dallas has endeavoured to give the explanations of the terms in as popular a form as possible.)


ABERRATION (in Optics).--In the refraction of light by a convex lens the rays passing through different parts of the lens are brought to a focus at slightly different distances--this is called SPHERICAL ABERRATION; at the same time the coloured rays are separated by the prismatic action of the lens and likewise brought to a focus at different distances--this is CHROMATIC ABERRATION.

ABNORMAL.--Contrary to the general rule.

ABORTED.--An organ is said to be aborted, when its development has been arrested at a very early stage.


ALGAE.--A class of plants including the ordinary sea-weeds and the filamentous fresh-water weeds.



ANALOGY.--That resemblance of structures which depends upon similarity of function, as in the wings of insects and birds. Such structures are said to be ANALOGOUS, and to be ANALOGUES of each other.

ANIMALCULE.--A minute animal: generally applied to those visible only by the microscope.

ANNELIDS.--A class of worms in which the surface of the body exhibits a more or less distinct division into rings or segments, generally provided with appendages for locomotion and with gills. It includes the ordinary marine worms, the earth-worms, and the leeches.

ANTENNAE.--Jointed organs appended to the head in Insects, Crustacea and Centipedes, and not belonging to the mouth.

ANTHERS.--The summits of the stamens of flowers, in which the pollen or fertilising dust is produced.


ARCHETYPAL.--Of or belonging to the Archetype, or ideal primitive form upon which all the beings of a group seem to be organised.


ASYMMETRICAL.--Having the two sides unlike.

ATROPHIED.--Arrested in development at a very early stage.

BALANUS.--The genus including the common Acorn-shells which live in abundance on the rocks of the sea-coast.

BATRACHIANS.--A class of animals allied to the Reptiles, but undergoing a peculiar metamorphosis, in which the young animal is generally aquatic and breathes by gills. (Examples, Frogs, Toads, and Newts.)

BOULDERS.--Large transported blocks of stone generally embedded in clays or gravels.


BRANCHIAE.--Gills or organs for respiration in water.

BRANCHIAL.--Pertaining to gills or branchiae.

CAMBRIAN SYSTEM.--A series of very ancient Palaeozoic rocks, between the Laurentian and the Silurian. Until recently these were regarded as the oldest fossiliferous rocks.

CANIDAE.--The Dog-family, including the Dog, Wolf, Fox, Jackal, etc.

CARAPACE.--The shell enveloping the anterior part of the body in Crustaceans generally; applied also to the hard shelly pieces of the Cirripedes.

CARBONIFEROUS.--This term is applied to the great formation which includes, among other rocks, the coal-measures. It belongs to the oldest, or Palaeozoic, system of formations.

CAUDAL.--Of or belonging to the tail.


CETACEA.--An order of Mammalia, including the Whales, Dolphins, etc., having the form of the body fish-like, the skin naked, and only the fore limbs developed.

CHELONIA.--An order of Reptiles including the Turtles, Tortoises, etc.



COCOON.--A case usually of silky material, in which insects are frequently enveloped during the second or resting-stage (pupa) of their existence. The term "cocoon-stage" is here used as equivalent to "pupa-stage."

COELOSPERMOUS.--A term applied to those fruits of the Umbelliferae which have the seed hollowed on the inner face.


COLUMN.--A peculiar organ in the flowers of Orchids, in which the stamens, style and stigma (or the reproductive parts) are united.

COMPOSITAE or COMPOSITOUS PLANTS.--Plants in which the inflorescence consists of numerous small flowers (florets) brought together into a dense head, the base of which is enclosed by a common envelope. (Examples, the Daisy, Dandelion, etc.)

CONFERVAE.--The filamentous weeds of fresh water.

CONGLOMERATE.--A rock made up of fragments of rock or pebbles, cemented together by some other material.


CORRELATION.--The normal coincidence of one phenomenon, character, etc., with another.

CORYMB.--A bunch of flowers in which those springing from the lower part of the flower stalks are supported on long stalks so as to be nearly on a level with the upper ones.

COTYLEDONS.--The first or seed-leaves of plants.

CRUSTACEANS.--A class of articulated animals, having the skin of the body generally more or less hardened by the deposition of calcareous matter, breathing by means of gills. (Examples, Crab, Lobster, Shrimp, etc.)

CURCULIO.--The old generic term for the Beetles known as Weevils, characterised by their four-jointed feet, and by the head being produced into a sort of beak, upon the sides of which the antennae are inserted.

CUTANEOUS.--Of or belonging to the skin.

DEGRADATION.--The wearing down of land by the action of the sea or of meteoric agencies.

DENUDATION.--The wearing away of the surface of the land by water.

DEVONIAN SYSTEM or FORMATION.--A series of Palaeozoic rocks, including the Old Red Sandstone.


DIFFERENTATION.--The separation or discrimination of parts or organs which in simpler forms of life are more or less united.

DIMORPHIC.--Having two distinct forms.--DIMORPHISM is the condition of the appearance of the same species under two dissimilar forms.

DIOECIOUS.--Having the organs of the sexes upon distinct individuals.

DIORITE.--A peculiar form of Greenstone.

DORSAL.--Of or belonging to the back.


ELYTRA.--The hardened fore-wings of Beetles, serving as sheaths for the membranous hind-wings, which constitute the true organs of flight.

EMBRYO.--The young animal undergoing development within the egg or womb.

EMBRYOLOGY.--The study of the development of the embryo.

ENDEMIC.--Peculiar to a given locality.



EPHEMEROUS INSECTS.--Insects allied to the May-fly.

FAUNA.--The totality of the animals naturally inhabiting a certain country or region, or which have lived during a given geological period.

FELIDAE.--The Cat-family.

FERAL.--Having become wild from a state of cultivation or domestication.

FLORA.--The totality of the plants growing naturally in a country, or during a given geological period.

FLORETS.--Flowers imperfectly developed in some respects, and collected into a dense spike or head, as in the Grasses, the Dandelion, etc.

FOETAL.--Of or belonging to the foetus, or embryo in course of development.

FORAMINIFERA.--A class of animals of very low organisation and generally of small size, having a jelly-like body, from the surface of which delicate filaments can be given off and retracted for the prehension of external objects, and having a calcareous or sandy shell, usually divided into chambers and perforated with small apertures.

FOSSILIFEROUS.--Containing fossils.


FRENUM (pl. FRENA).--A small band or fold of skin.

FUNGI (sing. FUNGUS).--A class of cellular plants, of which Mushrooms, Toadstools, and Moulds, are familiar examples.

FURCULA.--The forked bone formed by the union of the collar-bones in many birds, such as the common Fowl.

GALLINACEOUS BIRDS.--An order of birds of which the common Fowl, Turkey, and Pheasant, are well-known examples.

GALLUS.--The genus of birds which includes the common Fowl.

GANGLION.--A swelling or knot from which nerves are given off as from a centre.

GANOID FISHES.--Fishes covered with peculiar enamelled bony scales. Most of them are extinct.

GERMINAL VESICLE.--A minute vesicle in the eggs of animals, from which the development of the embryo proceeds.


GLAND.--An organ which secretes or separates some peculiar product from the blood or sap of animals or plants.

GLOTTIS.--The opening of the windpipe into the oesophagus or gullet.

GNEISS.--A rock approaching granite in composition, but more or less laminated, and really produced by the alteration of a sedimentary deposit after its consolidation.

GRALLATORES.--The so-called wading-birds (storks, cranes, snipes, etc.), which are generally furnished with long legs, bare of feathers above the heel, and have no membranes between the toes.

GRANITE.--A rock consisting essentially of crystals of felspar and mica in a mass of quartz.

HABITAT.--The locality in which a plant or animal naturally lives.

HEMIPTERA.--An order or sub-order of insects, characterised by the possession of a jointed beak or rostrum, and by having the fore-wings horny in the basal portion and membranous at the extremity, where they cross each other. This group includes the various species of bugs.

HERMAPHRODITE.--Possessing the organs of both sexes.


HOMOPTERA.--An order or sub-order of insects having (like the Hemiptera) a jointed beak, but in which the fore-wings are either wholly membranous or wholly leathery, The Cicadae, frog-hoppers, and Aphides, are well-known examples.

HYBRID.--The offspring of the union of two distinct species.

HYMENOPTERA.--An order of insects possessing biting jaws and usually four membranous wings in which there are a few veins. Bees and wasps are familiar examples of this group.

HYPERTROPHIED.--Excessively developed.

ICHNEUMONIDAE.--A family of hymenopterous insects, the members of which lay their eggs in the bodies or eggs of other insects.

IMAGO.--The perfect (generally winged) reproductive state of an insect.

INDIGENES.--The aboriginal animal or vegetable inhabitants of a country or region.

INFLORESCENCE.--The mode of arrangement of the flowers of plants.


INSECTIVOROUS.--Feeding on insects.

INVERTEBRATA, or INVERTEBRATE ANIMALS.--Those animals which do not possess a backbone or spinal column.

LACUNAE.--Spaces left among the tissues in some of the lower animals and serving in place of vessels for the circulation of the fluids of the body.

LAMELLATED.--Furnished with lamellae or little plates.

LARVA (pl. LARVAE).--The first condition of an insect at its issuing from the egg, when it is usually in the form of a grub, caterpillar, or maggot.

LARYNX.--The upper part of the windpipe opening into the gullet.


LEGUMINOSAE.--An order of plants represented by the common peas and beans, having an irregular flower in which one petal stands up like a wing, and the stamens and pistil are enclosed in a sheath formed by two other petals. The fruit is a pod (or legume).

LEMURIDAE.--A group of four-handed animals, distinct from the monkeys and approaching the insectivorous quadrupeds in some of their characters and habits. Its members have the nostrils curved or twisted, and a claw instead of a nail upon the first finger of the hind hands.

LEPIDOPTERA.--An order of insects, characterised by the possession of a spiral proboscis, and of four large more or less scaly wings. It includes the well-known butterflies and moths.

LITTORAL.--Inhabiting the seashore.

LOESS.--A marly deposit of recent (Post-Tertiary) date, which occupies a great part of the valley of the Rhine.

MALACOSTRACA.--The higher division of the Crustacea, including the ordinary crabs, lobsters, shrimps, etc., together with the woodlice and sand-hoppers.

MAMMALIA.--The highest class of animals, including the ordinary hairy quadrupeds, the whales and man, and characterised by the production of living young which are nourished after birth by milk from the teats (MAMMAE, MAMMARY GLANDS) of the mother. A striking difference in embryonic development has led to the division of this class into two great groups; in one of these, when the embryo has attained a certain stage, a vascular connection, called the PLACENTA, is formed between the embryo and the mother; in the other this is wanting, and the young are produced in a very incomplete state. The former, including the greater part of the class, are called PLACENTAL MAMMALS; the latter, or APLACENTAL MAMMALS, include the Marsupials and Monotremes (ORNITHORHYNCHUS).

MAMMIFEROUS.--Having mammae or teats (see MAMMALIA).

MANDIBLES.--in insects, the first or uppermost pair of jaws, which are generally solid, horny, biting organs. In birds the term is applied to both jaws with their horny coverings. In quadrupeds the mandible is properly the lower jaw.

MARSUPIALS.--An order of Mammalia in which the young are born in a very incomplete state of development, and carried by the mother, while sucking, in a ventral pouch (marsupium), such as the kangaroos, opossums, etc. (see MAMMALIA).

MAXILLAE.--in insects, the second or lower pair of jaws, which are composed of several joints and furnished with peculiar jointed appendages called palpi, or feelers.

MELANISM.--The opposite of albinism; an undue development of colouring material in the skin and its appendages.

METAMORPHIC ROCKS.--Sedimentary rocks which have undergone alteration, generally by the action of heat, subsequently to their deposition and consolidation.

MOLLUSCA.--One of the great divisions of the animal kingdom, including those animals which have a soft body, usually furnished with a shell, and in which the nervous ganglia, or centres, present no definite general arrangement. They are generally known under the denomination of "shellfish"; the cuttle-fish, and the common snails, whelks, oysters, mussels, and cockles, may serve as examples of them.

MONOCOTYLEDONS, or MONOCOTYLEDONOUS PLANTS.--Plants in which the seed sends up only a single seed-leaf (or cotyledon); characterised by the absence of consecutive layers of wood in the stem (endogenous growth), by the veins of the leaves being generally straight, and by the parts of the flowers being generally in multiples of three. (Examples, grasses, lilies, orchids, palms, etc.)

MORAINES.--The accumulations of fragments of rock brought down by glaciers.

MORPHOLOGY.--The law of form or structure independent of function.

MYSIS-STAGE.--A stage in the development of certain crustaceans (prawns), in which they closely resemble the adults of a genus (Mysis) belonging to a slightly lower group.

NASCENT.--Commencing development.

NATATORY.--Adapted for the purpose of swimming.

NAUPLIUS-FORM.--The earliest stage in the development of many Crustacea, especially belonging to the lower groups. In this stage the animal has a short body, with indistinct indications of a division into segments, and three pairs of fringed limbs. This form of the common fresh-water CYCLOPS was described as a distinct genus under the name of NAUPLIUS.

NEURATION.--The arrangement of the veins or nervures in the wings of insects.

NEUTERS.--Imperfectly developed females of certain social insects (such as ants and bees), which perform all the labours of the community. Hence, they are also called WORKERS.

NICTITATING MEMBRANE.--A semi-transparent membrane, which can be drawn across the eye in birds and reptiles, either to moderate the effects of a strong light or to sweep particles of dust, etc., from the surface of the eye.

OCELLI.--The simple eyes or stemmata of insects, usually situated on the crown of the head between the great compound eyes.

OESOPHAGUS.--The gullet.

OOLITIC.--A great series of secondary rocks, so called from the texture of some of its members, which appear to be made up of a mass of small EGG-LIKE calcareous bodies.

OPERCULUM.--A calcareous plate employed by many Molluscae to close the aperture of their shell. The OPERCULAR VALVES of Cirripedes are those which close the aperture of the shell.

ORBIT.--The bony cavity for the reception of the eye.

ORGANISM.--An organised being, whether plant or animal.


OSCULANT.--Forms or groups apparently intermediate between and connecting other groups are said to be osculant.


OVARIUM or OVARY (in plants).--The lower part of the pistil or female organ of the flower, containing the ovules or incipient seeds; by growth after the other organs of the flower have fallen, it usually becomes converted into the fruit.


OVULES (of plants).--The seeds in the earliest condition.

PACHYDERMS.--A group of Mammalia, so called from their thick skins, and including the elephant, rhinoceros, hippopotamus, etc.

PALAEOZOIC.--The oldest system of fossiliferous rocks.

PALPI.--Jointed appendages to some of the organs of the mouth in insects and Crustacea.

PAPILIONACEAE.--An order of plants (see LEGUMINOSAE), The flowers of these plants are called PAPILIONACEOUS, or butterfly-like, from the fancied resemblance of the expanded superior petals to the wings of a butterfly.

PARASITE.--An animal or plant living upon or in, and at the expense of, another organism.

PARTHENOGENESIS.--The production of living organisms from unimpregnated eggs or seeds.

PEDUNCULATED.--Supported upon a stem or stalk. The pedunculated oak has its acorns borne upon a footstool.

PELORIA or PELORISM.--The appearance of regularity of structure in the flowers of plants which normally bear irregular flowers.

PELVIS.--The bony arch to which the hind limbs of vertebrate animals are articulated.

PETALS.--The leaves of the corolla, or second circle of organs in a flower. They are usually of delicate texture and brightly coloured.

PHYLLODINEOUS.--Having flattened, leaf-like twigs or leafstalks instead of true leaves.

PIGMENT.--The colouring material produced generally in the superficial parts of animals. The cells secreting it are called PIGMENT-CELLS.

PINNATE.--Bearing leaflets on each side of a central stalk.



PLANTIGRADES.--Quadrupeds which walk upon the whole sole of the foot, like the bears.

PLASTIC.--Readily capable of change.

PLEISTOCENE PERIOD.--The latest portion of the Tertiary epoch.

PLUMULE (in plants).--The minute bud between the seed-leaves of newly-germinated plants.

PLUTONIC ROCKS.--Rocks supposed to have been produced by igneous action in the depths of the earth.

POLLEN.--The male element in flowering plants; usually a fine dust produced by the anthers, which, by contact with the stigma effects the fecundation of the seeds. This impregnation is brought about by means of tubes (POLLEN-TUBES) which issue from the pollen-grains adhering to the stigma, and penetrate through the tissues until they reach the ovary.

POLYANDROUS (flowers).--Flowers having many stamens.

POLYGAMOUS PLANTS.--Plants in which some flowers are unisexual and others hermaphrodite. The unisexual (male and female) flowers, may be on the same or on different plants.

POLYMORPHIC.--Presenting many forms.

POLYZOARY.--The common structure formed by the cells of the Polyzoa, such as the well-known seamats.

PREHENSILE.--Capable of grasping.

PREPOTENT.--Having a superiority of power.

PRIMARIES.--The feathers forming the tip of the wing of a bird, and inserted upon that part which represents the hand of man.

PROCESSES.--Projecting portions of bones, usually for the attachment of muscles, ligaments, etc.

PROPOLIS.--A resinous material collected by the hivebees from the opening buds of various trees.

PROTEAN.--Exceedingly variable.

PROTOZOA.--The lowest great division of the animal kingdom. These animals are composed of a gelatinous material, and show scarcely any trace of distinct organs. The Infusoria, Foraminifera, and sponges, with some other forms, belong to this division.

PUPA (pl. PUPAE).--The second stage in the development of an insect, from which it emerges in the perfect (winged) reproductive form. In most insects the PUPAL STAGE is passed in perfect repose. The CHRYSALIS is the pupal state of butterflies.

RADICLE.--The minute root of an embryo plant.

RAMUS.--One half of the lower jaw in the Mammalia. The portion which rises to articulate with the skull is called the ASCENDING RAMUS.

RANGE.--The extent of country over which a plant or animal is naturally spread. RANGE IN TIME expresses the distribution of a species or group through the fossiliferous beds of the earth's crust.




RODENTS.--The gnawing Mammalia, such as the rats, rabbits, and squirrels. They are especially characterised by the possession of a single pair of chisel-like cutting teeth in each jaw, between which and the grinding teeth there is a great gap.

RUBUS.--The bramble genus.

RUDIMENTARY.--Very imperfectly developed.

RUMINANTS.--The group of quadrupeds which ruminate or chew the cud, such as oxen, sheep, and deer. They have divided hoofs, and are destitute of front teeth in the upper jaw.


SARCODE.--The gelatinous material of which the bodies of the lowest animals (Protozoa) are composed.

SCUTELLAE.--The horny plates with which the feet of birds are generally more or less covered, especially in front.

SEDIMENTARY FORMATIONS.--Rocks deposited as sediments from water.

SEGMENTS.--The transverse rings of which the body of an articulate animal or annelid is composed.

SEPALS.--The leaves or segments of the calyx, or outermost envelope of an ordinary flower. They are usually green, but sometimes brightly coloured.

SERRATURES.--Teeth like those of a saw.

SESSILE.--Not supported on a stem or footstalk.

SILURIAN SYSTEM.--A very ancient system of fossiliferous rocks belonging to the earlier part of the Palaeozoic series.

SPECIALISATION.--The setting apart of a particular organ for the performance of a particular function.



STERNUM.--The breast-bone.

STIGMA.--The apical portion of the pistil in flowering plants.

STIPULES.--Small leafy organs placed at the base of the footstalks of the leaves in many plants.

STYLE.--The middle portion of the perfect pistil, which rises like a column from the ovary and supports the stigma at its summit.

SUBCUTANEOUS.--Situated beneath the skin.

SUCTORIAL.--Adapted for sucking.

SUTURES (in the skull).--The lines of junction of the bones of which the skull is composed.

TARSUS (pl. TARSI).--The jointed feet of articulate animals, such as insects.

TELEOSTEAN FISHES.--Fishes of the kind familiar to us in the present day, having the skeleton usually completely ossified and the scales horny.

TENTACULA or TENTACLES.--Delicate fleshy organs of prehension or touch possessed by many of the lower animals.

TERTIARY.--The latest geological epoch, immediately preceding the establishment of the present order of things.

TRACHEA.--The windpipe or passage for the admission of air to the lungs.

TRIDACTYLE.--Three-fingered, or composed of three movable parts attached to a common base.

TRILOBITES.--A peculiar group of extinct crustaceans, somewhat resembling the woodlice in external form, and, like some of them, capable of rolling themselves up into a ball. Their remains are found only in the Palaeozoic rocks, and most abundantly in those of Silurian age.

TRIMORPHIC.--Presenting three distinct forms.

UMBELLIFERAE.--An order of plants in which the flowers, which contain five stamens and a pistil with two styles, are supported upon footstalks which spring from the top of the flower stem and spread out like the wires of an umbrella, so as to bring all the flowers in the same head (UMBEL) nearly to the same level. (Examples, parsley and carrot.)

UNGULATA.--Hoofed quadrupeds.

UNICELLULAR.--Consisting of a single cell.

VASCULAR.--Containing blood-vessels.

VERMIFORM.--Like a worm.

VERTEBRATA or VERTEBRATE ANIMALS.--The highest division of the animal kingdom, so called from the presence in most cases of a backbone composed of numerous joints or VERTEBRAE, which constitutes the centre of the skeleton and at the same time supports and protects the central parts of the nervous system.

WHORLS.--The circles or spiral lines in which the parts of plants are arranged upon the axis of growth.

WORKERS.--See neuters.

ZOEA-STAGE.--The earliest stage in the development of many of the higher Crustacea, so called from the name of ZOEA applied to these young animals when they were supposed to constitute a peculiar genus.

ZOOIDS.--In many of the lower animals (such as the Corals, Medusae, etc.) reproduction takes place in two ways, namely, by means of eggs and by a process of budding with or without separation from the parent of the product of the latter, which is often very different from that of the egg. The individuality of the species is represented by the whole of the form produced between two sexual reproductions; and these forms, which are apparently individual animals, have been called ZOOIDE.

INDEX. 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 of --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

End of Project Gutenberg Etext Origin of Species, 6th Edition, by Darwin