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new animal or plant must have been conjured into existence by an invisible and unintelligible Power, and it has correlated the whole series of forms of life into a comprehensible record of progress. Species, living and dead, that were but the toys with which naturalists have been playing since Aristotle's day, have for us suddenly become the legions, which, on forgotten continents, and beneath oceans whose beds now form the mountain tops of earth, have fought out the great battle of life.

APPENDICES.

APPENDIX A.

By the animal kingdom is meant the whole series of living and extinct species of animals. It has been variously divided into groups. One of the most comprehensible as well as natural classifications gives eight sub-kingdoms, as follows:1

1. Protozoa, the animalcule sub-kingdom-animals which have neither a general body-cavity, nor a nervous system.

2. Polystomata, the sponge sub-kingdom — animals which have an internal cavity with a threelayered wall, one outlet, and usually many inlets, with no parts or organs set aside for special purposes, but consisting of many cells.

3. Calenterata, the jelly-fish sub-kingdom-animals with a stomach-cavity, and a body-cavity extending out from this. The parts of the body are arranged regularly around a centre as the spokes of

1 The language a little simplified from Macalister's Zoülogy: Invertebrata, p. 14.

a wheel are around the hub; that is, they have a radiate symmetry.

4. Echinodermata, the star-fish sub-kingdomanimals with a body-cavity separate from the stomach, a nervous system, and a system of water-tubes, which aid the animal in locomotion: the symmetry more or less completely radiate.

5. Vermes, the worm sub-kingdom - animals which consist of two halves, or have bilateral symmetry, are composed of a series of joints or segments, have no jointed limbs, and have a water-tube system, which does not aid in locomotion.

6. Mollusca, the shell-fish sub-kingdom — animals which have soft bodies covered by a leathery portion called the "" 'mantle," no jointed limbs, a heart and blood-vessels (or something resembling them), forming a circulatory system, often a shell outside the body, and frequently an unsymmetrical nervous system; that is, one in which there are not two equal or nearly equal sides to each part.

7. Arthropoda, the crab, spider, and insect subkingdom — animals which have bodies made up of a series of joints, a symmetrical nervous system, a skeleton outside of the body, and jointed limbs.

8. Vertebrates, the back-boned sub-kingdom — animals which have a skeleton within the body, a brain, and a back-bone.

The most important of the sub-kingdoms is further divided as follows:

Fishes.

Vertebrata.

Amphibians (toads, frogs, newts, etc.).
Reptiles (snakes, lizards, etc.).

Birds.

Mammals, or warm-blooded quadrupeds.

As an example of the way in which a class is subdivided into smaller groups, the mammalia may be taken. This class consists of sixteen orders, as follows:

(1) Monotremes (Australian duck-mole, etc.).
(2) Marsupials (kangaroo, opossum, etc.).
(3) Edentates (ant-eater and armadillo).
(4) Sloths.

(5) Sirens (dugong, manatee, etc.).

(6) Ungulates (horse, rhinoceros, hog, deer). (7) Cetacea (whales, etc.).

(8) Pinnipeds (seals and walruses).

(9) Carnivores (cat, dog, weasel, and bear).

(10) Hyracoids (conies).

(11) Rodents (rats, mice, squirrels, etc.).

(12) Proboscides (elephants).

(12) Lemurs (aye-aye, etc.).

(14) Insectivores (shrews, moles, hedgehogs).

(15) Cheiropters (bats).

(16) Primates (monkeys, apes, and man).

The subdivisions of the vegetable kingdom, according to one of the simplest plans of classification, are as follows:

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