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leaves. The parts of the flowers are generally in multiples of five.

Differentiation. — 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 ap-
pearance of the same species under two dissimilar forms.

DiCECious. — 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, characterized 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 mem-
braneous 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

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.

Feled^. — 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.

Fcetal. — Of or belonging to the foetus, or embryo in course of development.

FoRAMiNiFERA. — ^A class of animals of very low organization 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 (pi. Frena). — A small band or fold of skin.

Fungi (sing. Fungus). — A class of cellular plants, of which Mushrooms, Toad-
stools, 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.

Callus. — ^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 sub-
jected 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 con-

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

Habitat. — The locality in which a plant or animal naturally lives.

Hemiptera. — An order or sub-order of Insects, characterized by the possession of a
jointed beak or rostrum, and by having the fore-wings horny in the basal portion
and membraneous at the extremity, where they cross each other. This group
includes the various species of Bugs.

Hermaphrodite. Possessing the organs of both sexes.

Homology. — The 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 centi-
pede, 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 homol-
ogous with leaves.

Homoptera. — ^An order or sub-order of Insects having (like the Hemiptera) a
jointed beak, but in which the fore-wings are either wholly membraneous or
wholly leathery. The Cicadce, 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 mem-
braneous wings in which there are a few veins. Bees and Wasps are familiar*
examples of this group.

Hypertrophied. — Excessively developed.

IcHNEUMONiD/^. — ^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.

Indigens. — The aboriginal animal or vegetable inhabitants of a country or region.

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.


Lacuna. — 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 (pi. Larv.^). — 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. Lawrence, whence the name. It is in these
that the earliest known traces of organic bodies have been found.

Leguminos/E. — An order of plants represented by the common Pease 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).

Lemurjd^. — A group of four-handed animals, distinct from the Monkeys, and ap-
proaching 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.

LEProoPTERA. — ^An order of Insects, characterized 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 Wood-lice and Sand-hoppers.

Mammalia. — The highest class of animals, including the ordinary hairy quadru-
peds, the Whales and Man, and characterized by the production of living
young which are nourished after birth by milk from the teats {Mammce, Mam-
mary 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 mammce 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.

Marsupl\ls. — An order of Mammalia in which the young are born in a very in-
complete state of development and carried by the mother, while sucking, in a
ventral pouch (marsupium), such as the Kangaroos, Opossums, etc. (see

Maxilla in Insects. — ^The second or lower pair of jaws, which are composed of
several joints and furnished with peculiar jointed appendages called palpi or

Melanism. — The opposite of Albinism; an undue development of coloring material
in the skin and its appendages.

Metamorphic Rocks. — Sedimentary rocks which have undergone alteration, gen-
erally by the action of heat, subsequent 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 "shell-fish"; 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); characterized 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 gen-
erally 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 (Pra^vns), in
which they closely resemble the adults of a genus [My sis) 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, espe-
cially 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.

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.

Neuters. — Imperfectly developed females of certain social insects (such as Ants
and Bees), which perform all the labors of the community. Hence they are
also called workers.

Ocelli. — The simple eyes or stemmata of Insects, usually situated on the crown of

the head between the great compound eyes.
CEsoPHAGUS. — The gullet.
OoLmc. — ^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

Operculum. — ^A calcareous plate employed by many Mollusca 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 organized 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.
Ova. — Eggs.
Ovarium or Ovary (in plants). — The lower part of the pistil or female organ of

the flow^er, containing the o\Tiles or incipient seeds; by growth after the other

organs of the flower have fallen, it usually becomes converted into the fruit.


OviGEROUS. — Egg-bearing.

Ovules (of plants). — The seeds in the earliest condition.

Pachyderms. — A group of Mammalia so called from their thick skins, and includ-
ing the Elephant, Rhinoceros, Hippopotamus, etc.

Pal/EOZoic. — The oldest system of fossiliferous rocks.

Palpi. — Jointed appendages to some of the organs of the mouth in Insects and

Papilionace/e. — ^An order of Plants (see Leguminos^). — 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

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 articu-

Petals. — The leaves of the corolla, or second circle of organs in a flower. They
are usually of delicate texture and brightly colored.

Phyllodineous. — Having flattened, leaf -like twigs or leaf -stalks instead of true

Pigment. — The coloring 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.

Plagentalia, Placentata, or Placental Mammals. — See Mammalia.

Plantigrades. — Quadrupeds which walk upon the whole sole of the foot, like the

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 germi-
nated 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 Sea-mats.
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 Hive-Bees 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 (pi. Pup^). — 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.

Ramus. — One half of the lower jaw in the Mammalia. The portion which rises to

articulate with the skull is called the ascending ramus.
Radicle. — The minute root of an embryo plant.
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 organized than might be expected from its

early stages and known relationships, it is said to undergo a retrograde develop-
ment or metamorphosis.
Rhizopods. — A class of lowly organized animals (Protozoa), having a gelatinous

body, tJie surface of which can be protruded in the form of root-Hke processes

or nlaments, which serve for locomotion and the prehension of food. The most

important order is that of the Foraminifera.
Rodents. — The gnawing Mammalia, such as Rats, Rabbits and Squirrels. They

are especially characterized 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 at-

Sarcode. — The gelatinous material of which the bodies of the lowest animals
(Protozoa) are composed.


ScuTELL^E. — The horny plates with which the feet ' urds 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 colored.
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.
Specialization. — 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


Tarsus (pi. 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
Wood-lice in external form, and, like some of them, capable of rolling them-
selves 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.

Umbellifer^. — An order of plants in which the flowers, which contain five stamens
and a pistil with two styles, are supported upon foot stalks 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 quadi' ^^ds.
Unicellular. — Consisting of a single cell.

Vascular. — Containing blood-vessels.

Vermiform. — Like a worm.

Vertebrata; or Vertebrate Animals. — The highest division of the Animal King-
dom, so called from the presence in most cases of a backbone composed of
numerous joints or vertebrce, 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.) repro-
duction 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 zooids.

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