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ORDER V. Natatores. Divers and swimmers. Legs short, toes webbed. Examples, gull, duck, albatross.

ORDER VI. Columbæ. Like Gallinæ but with weaker legs. Examples, dove, pigeon.

ORDER VII. Picaria.


Two toes point forward, two backward, and adaptation for climbing. Long, strong bill.



Herrick, Text-book in General Zoology, Chaps. XXII, XXIII. American Book Company.

Beebe, The Bird. Henry Holt and Company.

Nature Study Leaflets, XXII, XXIII, XXIV, XXV. N.Y. Department of Agriculture.


Apgar, Birds of the United States. American Book Company.
Beebe, The Bird. Henry Holt and Company.

Bulletins of U.S. Department of Agriculture, Division of Biological Survey, Nos. 1. 6, 15, 17. See also Year Book, 1899.

Chapman, Bird Life. D. Appleton and Company.

Riverside Natural History, Vol. IV. Houghton, Mifflin, and Company.


The Rabbit. Living rabbits may be kept in the schoolroom in a box open at one end, the open end protected by a door covered with wire screening. A rabbit thus kept, if given a little care, soon becomes accustomed to his surroundings and will prove a very acceptable addition to the laboratory. Adaptations to Its Life. - The rabbit in a wild state makes its home under clumps of dried grass, brush, and the like. Its English cousins make burrows in the ground. The rabbit escapes observation from its enemies by means of its color, which often closely resembles that of the thickets in which it hides. Notice the body covering; is it uniform in color and thickness? The hair forms a protection from the cold. In summer the color of the coat is more earthlike than in the winter. Some arctic forms undergo a complete change of coat from gray in summer to white in the winter.

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Compare the fore limbs of the rabbit with your own arms; do you find upper arm, forearm, wrist, and hand? In the same manner find the parts corresponding to thigh, shank, and foot in your own leg. Notice the different methods of locomotion in the rabbit; seek the ways in which the limbs of the rabbit are adapted to the function of locomotion. Notice the feet to see if they are adapted for digging or for any other purpose.

The rabbit relies principally on swiftness and agility in flight rather than in ability to cope with an enemy with teeth and claws. Frequently they will remain in absolute quiet, allowing their arch-enemy, the dog, to pass close to them, relying on their protective coloration to escape notice. When chased by the dog, they have the instinct of running in a circle and will during the chase suddenly jump to one side at a sharp angle in order to throw the dog off the scent.

Wood hare. From photograph loaned by the American Museum of Natural History.

The teeth are of considerable importance in connection with the food and the method of obtaining food. Notice the prominent cutting teeth (the incisors). Note the cleft upper lip. Feed a carrot to the rabbit and determine the use of the cleft. Which jaws move during feeding? Notice that they move sidewise as well as vertically; this horizontal movement is of considerable use in grinding the food.

If you examine the prepared skull of a rabbit the different kinds of teeth may be easily identified and their functions learned. In front are found the incisors. How many in each jaw? Separated from the incisors by a gap are the molars or grinding teeth. How are such teeth adapted to their function? With a hand glass note the position of the

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Notice the shape and position of the external ear. Compare with the head in length. The external ear collects the sound waves and sends them into the internal ear, the true organ of hearing (see page 421). Test the animal's response to sounds, especially when the maker of the sound is hidden. Is the hearing of the rabbit acute? (The above problem makes a good series of home experiments.)

Notice the mobility of the nose, especially when the animal is sniffing. By means of some strongly smelling substances, determine whether the rabbit easily perceives odors. Try to determine whether the saying that the whiskers of a cat or rabbit are used to smell with has any foundation in fact. Notice whether the hairs move at the same time the odor is presented.

SKELETON.-The rabbit is provided with a bony skeleton which gives support to the muscles and also protects the delicate organs of digestion, res

piration, etc., under the ribs. Compare with the skeleton of man in this respect (see page 372). The bones of the skeleton may be divided into two groups as in man, those of the axial skeleton, the vertebræ, and bones of the head; and those of the appendages, including the pectoral and pelvic arches, where the appendages are attached to the axial skeleton of the rabbit The chief differences

The skeleton of a monkey, a typical mammal.

skeleton. Part for part and almost bone for bone the may be compared with that of man (see page 372). exist in the appendages, where the erect animal, man, has the bones of the


hand and foot considerably modified from those of an animal which uses all the appendages for locomotion. The digestive tract is also much like that of man. (See page 330.)

ORGANS OF DIGESTION. -The digestive glands, and the salivary, gastric, intestinal, and pancreatic glands have nearly all the same position and functions. The glands which act upon starch are better developed in the rabbit than in man because of the predominance of starchy foods used by the rabbit. The intestine is longer than in flesh-eating animals.

CIRCULATION.. In all mammals (of which the rabbit is an example) the blood in its circulation passes through a four-chambered heart. There is a system of closed blood tubes which, according to the position and function, are named arteries, veins, and capillaries. The whole process of circulation is identical with that process in man (see Circulation, page 350). The lungs and heart are separated from the lower part of the body cavity by means of a thin-walled plate of muscle, called the diaphragm. This diaphragm occurs in all mammals.

Oxygen is taken up by the blood and respiration takes place in a similar manner to that process in man.

In like manner the organs of excretion of nitrogenous waste, the skin and kidneys, eliminate the waste from the body in the same manner as it is done in man.

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NERVOUS SYSTEM. The brain and central nervous system of the rabbit are well developed. A brain, which has a large cerebrum and other characteristics of the brain of man, supplies sense organs through twelve cranial (brain) nerves (see The Nervous System, page 400). The senses, especially those of sight and hearing, are also highly developed and are very acute. We have seen that the eyes are so placed that the animal is able to look to the sides and behind without turning the head. Organs of taste, the taste buds, such as are found in man, are also developed in the rabbit. The sense of touch appears to be well developed over the entire body, but is especially keen in the region of the nose (see The Senses, page 419).

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Characters of Mammals. Vertebrate animals which have a hairy coat and which nurse the young by means of milk-producing glands (the mammary glands) are called mammals. Such evidently is the rabbit. Rats, woodchucks, cattle, dogs, cats, and man are all examples of this group. Man is by far the best mentally developed of all this group and is therefore spoken of as the highest of the mammals.

The common house rat. From photograph, about one fourth natural size.

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The mammals are divided into a number of smaller

groups, called orders. The rabbit, because it has prominent incisor teeth and no canine (dog) teeth, is placed in the order of the rodents. Among the fourteen orders of mammals the rodents are estimated to comprise fully one half of the total number of species.

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Although most rodents may be considered as pests (as the rat and mouse), others are of use to man. Some of this order furnish food to man, as the rabbit, hares, and squirrels. The fur of the beaver, one of the largest of this order, is of considerable value, as are the coats of several other rodents. The fur of the rabbit is used in the manufacture of felt hats. The quills of the porcupines (greatly developed and stiffened hairs) have a slight commercial value.

OTHER ORDERS OF MAMMALS. The lowest are the monotremes, animals which lay eggs like the birds, although they are provided with hairy covering like other mammals. Such are the spiny ant-eater and the duck mole.

All other mammals bring forth their young alive. The kangaroos and opossum, however, are provided with a pouch on the ventral side of the body in which the very immature, blind, and helpless young are nourished until they are able to care for themselves. These pouched animals are called marsupials.



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The other mammals, in which the young are born able to care for themselves, and have the form of the adult, may be briefly classified as follows:

CHARACTER Edentates Toothless or with very simple teeth

Virginia opossum. From photograph, one eighth natural size, by N. F. Davis.

Incisor teeth, chisel-shaped, usu-
ally two above and two be-

Adapted to marine life, teeth
sometimes platelike




Beaver, Rat

Porcupine, Rabbit



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