Science
Read books online » Science » The Origin of Species by means of Natural Selection (6th ed) by Charles Darwin (inspirational novels .txt) 📖

Book online «The Origin of Species by means of Natural Selection (6th ed) by Charles Darwin (inspirational novels .txt) 📖». Author Charles Darwin



1 ... 96 97 98 99 100 101 102 103 104 105
Go to page:
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 formed.

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

Corncrake

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

1 ... 96 97 98 99 100 101 102 103 104 105
Go to page:

Free ebook «The Origin of Species by means of Natural Selection (6th ed) by Charles Darwin (inspirational novels .txt) 📖» - read online now

Comments (0)

There are no comments yet. You can be the first!
Add a comment