|Page 121||Contents - 'The Origin of Species' by Charles Darwin||prev page next page|
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 size.
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
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.
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 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.
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.