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On the Origin of Species, 6th Edition by Charles Darwin

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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.

CEPHALOPODS.--The highest class of the Mollusca, or soft-bodied animals,
characterised by having the mouth surrounded by a greater or less number of
fleshy arms or tentacles, which, in most living species, are furnished with
sucking-cups. (Examples, Cuttle-fish, Nautilus.)

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.

CIRRIPEDES.--An order of Crustaceans including the Barnacles and Acorn-
shells. Their young resemble those of many other Crustaceans in form; but
when mature they are always attached to other objects, either directly or
by means of a stalk, and their bodies are enclosed by a calcareous shell
composed of several pieces, two of which can open to give issue to a bunch
of curled, jointed tentacles, which represent the limbs.

COCCUS.--The genus of Insects including the Cochineal. In these the male
is a minute, winged fly, and the female generally a motionless, berry-like

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.

COLEOPTERA.--Beetles, an order of Insects, having a biting mouth and the
first pair of wings more or less horny, forming sheaths for the second
pair, and usually meeting in a straight line down the middle of the back.

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.

COROLLA.--The second envelope of a flower usually composed of coloured,
leaf-like organs (petals), which may be united by their edges either in the
basal part or throughout.

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.

DICOTYLEDONS, or DICOTYLEDONOUS PLANTS.--A class of plants characterised by
having two seed-leaves, by the formation of new wood between the bark and
the old wood (exogenous growth) and by the reticulation of the veins of the
leaves. The parts of the flowers are generally in multiples of five.

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.

EDENTATA.--A peculiar order of Quadrupeds, characterised by the absence of
at least the middle incisor (front) teeth in both jaws. (Examples, the
Sloths and Armadillos.)

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.

ENTOMOSTRACA.--A division of the class Crustacea, having all the segments
of the body usually distinct, gills attached to the feet or organs of the
mouth, and the feet fringed with fine hairs. They are generally of small

EOCENE.--The earliest of the three divisions of the Tertiary epoch of
geologists. Rocks of this age contain a small proportion of shells
identical with species now living.

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.

FOSSORIAL.--Having a faculty of digging. The Fossorial Hymenoptera are a
group of Wasp-like Insects, which burrow in sandy soil to make nests for
their young.

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

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.

GLACIAL PERIOD.--A period of great cold and of enormous extension of ice
upon the surface of the earth. It is believed that glacial periods have
occurred repeatedly during the geological history of the earth, but the
term is generally applied to the close of the Tertiary epoch, when nearly
the whole of Europe was subjected to an arctic climate.

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.

HOMOLOGY.--That relation between parts which results from their development
from corresponding embryonic parts, either in different animals, as in the
case of the arm of man, the fore-leg of a quadruped, and the wing of a
bird; or in the same individual, as in the case of the fore and hind legs
in quadrupeds, and the segments or rings and their appendages of which the
body of a worm, a centipede, etc., is composed. The latter is called
serial homology. The parts which stand in such a relation to each other
are said to be homologous, and one such part or organ is called the
homologue of the other. In different plants the parts of the flower are
homologous, and in general these parts are regarded as homologous with

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

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

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

INFUSORIA.--A class of microscopic animalcules, so called from their having
originally been observed in infusions of vegetable matters. They consist
of a gelatinous material enclosed in a delicate membrane, the whole or part
of which is furnished with short vibrating hairs (called cilia), by means
of which the animalcules swim through the water or convey the minute
particles of their food to the orifice of the mouth.

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.

LAURENTIAN.--A group of greatly altered and very ancient rocks, which is
greatly developed along the course of the St. Laurence, whence the name.
It is in these that the earliest known traces of organic bodies have been

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

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

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

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

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

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.

ORTHOSPERMOUS.--A term applied to those fruits of the Umbelliferae which
have the seed straight.

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

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.

PISTILS.--The female organs of a flower, which occupy a position in the
centre of the other floral organs. The pistil is generally divisible into
the ovary or germen, the style and the stigma.


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.

RETINA.--The delicate inner coat of the eye, formed by nervous filaments
spreading from the optic nerve, and serving for the perception of the
impressions produced by light.

RETROGRESSION.--Backward development. When an animal, as it approaches
maturity, becomes less perfectly organised than might be expected from its
early stages and known relationships, it is said to undergo a RETROGRADE

RHIZOPODS.--A class of lowly organised animals (Protozoa), having a
gelatinous body, the surface of which can be protruded in the form of
root-like processes or filaments, which serve for locomotion and the
prehension of food. The most important order is that of the Foraminifera.

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.

SACRAL.--Belonging to the sacrum, or the bone composed usually of two or
more united vertebrae to which the sides of the pelvis in vertebrate
animals are attached.

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.

SPINAL CORD.--The central portion of the nervous system in the Vertebrata,
which descends from the brain through the arches of the vertebrae, and
gives off nearly all the nerves to the various organs of the body.

STAMENS.--The male organs of flowering plants, standing in a circle within
the petals. They usually consist of a filament and an anther, the anther
being the essential part in which the pollen, or fecundating dust, is

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

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.


Aberrant groups

Abyssinia, plants of



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


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


Antarctic islands, ancient flora of


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

Apes, not having acquired intellectual powers

Aphides attended by ants

Aphis, development of


Arab horses

Aralo-Caspian Sea


Archiac, M. de, on the succession of species

Artichoke, Jerusalem

Ascension, plants of

Asclepias, pollen of



Asses, striped
--improved by selection


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


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
--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

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

--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


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



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

Cave, inhabitants of, blind


Celts, proving antiquity of man

Centres of creation

Cephalopodae, structures of eyes
--development of

Cercopithecus, tail of

Ceroxylus laceratus


Cetacea, teeth and hair
--development of the whalebone


Ceylon, plants of

Chalk formation

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


Checks to increase

Chelae of Crustaceans

Chickens, instinctive tameness of

Chironomus, its asexual reproduction


Chthamalus, cretacean species of

Circumstances favourable to selection of domestic products
--to natural selection

Cirripedes capable of crossing
--carapace aborted
--their ovigerous frena
--larvae of

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

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


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


Collections, palaeontological, poor

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

Columba livia, parent of domestic pigeons


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


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

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


Correlated variation in domestic productions


Creation, single centres of


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

Crustaceans, their chelae


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



Drones killed by other bees

Duck, domestic, wings of, reduced
--beak of


Dugong, affinities of

Dung-beetles with deficient tarsi


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

Ears, drooping, in domestic animals

Earth, seeds in roots of trees
--charged with seeds

Echinodermata, their pedicellariae


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


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


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

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
--thickness of, in Britain

--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


Frogs on islands

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

Fuci, crossed

Fur, thicker in cold climates


Galapagos Archipelago, birds of
--productions of

Galaxias, its wide range


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

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


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


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


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

Hartung, M., on boulders in the Azores


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


Helix pomatia, resisting salt water

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


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



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

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


Hydra, structure of

Hymenoptera, fighting

Hymenopterous insect, diving



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
--their resemblance to certain objects

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


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


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

Mammals, fossil, in secondary formation

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


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


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


Mons, Van, on the origin of fruit-trees


Moquin-Tandon, on sea-side plants


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



Myrmica, eyes of

Nageli, on morphological characters

Nails, rudimentary

Nathusius, Von, on pigs

Natural history, future progress of

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
--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


Partridge, with ball of dirt attached to foot

Parts greatly developed, variable

Parus major


Peaches in United States

Pear, grafts of


Pelargonium, flowers of
--sterility of


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
--destroyed by insects
--in midst of range, have to struggle with other plants
--nectar of
--fleshy, on sea-shores
--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

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