The Vertebrated Animals
Have a backbone divided into vertebræ or joints, whence they take their name. They have also separate senses for hearing, seeing, tasting, smelling, and feeling; a distinct head, with a mouth opening by two horizontal jaws; a muscular heart, and red blood. The four classes of Vertebrata and their orders are as follow:—
I. The Mammalia are all furnished with mammæ, or teats, through which they give milk to their young, which they bring forth alive. They have warm blood, which all circulates from the heart through the lungs, and returns to the heart before it passes through the body. Their skins are naked, or covered with wool or hair, and their mouths are generally furnished with teeth. There are eleven orders, which are thus distinguished:—
Section I — Unguiculated Animals, or Mammalia Having Nails or Claws
I. Bimana, or two-handed. This order contains only the human species.
II. Quadrumana, or four-handed. This order contains the apes, baboons, and monkeys, and the lemurs.
III. Cheiroptera, the bat family.
IV. Carnivora, or beasts of prey. This order is divided into the following three tribes:—
1. The Insectivora, consisting of those animals which live upon insects, as the hedgehog, the shrew, and the mole.
2. The Carnivora proper, consisting chiefly of the cat family, including lions, tigers, and their allies; the bear family, including the badger, the coati-mondi, the racoon, &c.; the dog family, including the wolf and the fox; the weasel family; the civet-cats; and the hyæna.
3. The Amphibia, consisting of the seals, and other allied animals.
V. Marsupialia, including the opossums and the kangaroos.
VI. Monothrema, containing the Echidna and Ornithorhynchus of Australia.
VII. Rodentia, or gnawing animals. The principal of these are the squirrel family, mice and rats, hares and rabbits, the beaver, the porcupine, and the guinea-pig.
VIII. Edentata, or toothless animals, that is, without front teeth. The principal of these are the sloths, the armadillos, and the ant-eaters.
Section II — Ungulated or Hoofed Mammalia
IX. Pachydermata, or thick-skinned animals. The principal of these are the elephant, the hippopotamus, the rhinoceros; the horse family, including the ass, the mule, the zebra, and the quagga; the wild boar family, and the tapir.
X. Ruminantia, or ruminating animals, the principal of which are the camel family, the deer family, the giraffe, the antelope family, the goat family, the sheep family, and the ox family.
Section III.—Aquatic Mammalia, having no Hind Limbs, and the Fore Limbs converted into Fins.
XI. Cetacea, or sea mammalia, the principal of which are the whale family, the dolphin family, the manati, the porpoise family, and the narwhal, or sea-unicorn.