What is the colour of a wild rabbit? Does the colour render the animal less conspicuous? Are tame rabbits so often of this colour? Why not? Watch a tame rabbit, noticing especially the movements of its nostrils, whiskers, and ears, and its method of feeding. Try to see how it gnaws the bars of its hutch.
2. Fur.—Examine a dead rabbit. With what is the skin covered? What are the differences between the fur of a rabbit, the hair of a dog, and the wool of a sheep? Is fur curly? Does it lie flat on the skin? Does it consist of different sizes of hair—short, fine hairs and long, thicker ones? What other animals do you know which have fur?
3. The head.—(a) The whiskers.—On what parts of the head are the longest hairs found? How do these differ, apart from length, from ordinary hairs? What other common animals have whiskers? Do such animals often make their way through narrow passages? What do you suppose is the use of the whiskers?
(b) The skull.—Feel the bones of the head through the skin, and make out the rounded brain-case, the ridge above and the arch below each eye, and the positions of the jaws.
(c) The external ears.—Examine the large ear-flaps. Notice that the upper parts are thin and almost transparent, and that the lower parts are gristly and lead into the interior of the head.
(d) The eyes.—Notice that the eyes are at the sides of the head. Is this position an advantage to the rabbit? Examine, in each eye, the upper and lower lids; and also, in the angle of the eye next the nose, the third eyelid—a fold of white skin. Take hold of this fold with the forceps and see that it is easily pulled over the eyeball. Look in a mirror and see the little fleshy body which occupies a similar position in your own eye; this corresponds to the rabbit’s third eyelid. In the visible part of the rabbit’s eyeball notice the round dark pupil in the middle (contrast the pupil of a cat’s eye); the coloured ring (the iris) surrounding the pupil; and the “white” (called the sclerotic) surrounding the iris.
(e) The lips and nostrils.—Notice how the upper lip is split in the middle line, so as to show the front teeth. What is the use of the split? Notice the grooves passing from the upper lip to the nostrils.
(f) The inside of the mouth.—Open the rabbit’s mouth and notice:
(i) The two gnawing or incisor teeth in the lower jaw, and the pair of strongly-grooved incisors which are so conspicuous in the upper jaw. Just behind the large, upper incisors two smaller incisors may be felt with the finger. Separated by a wide space from the incisors are the grinding teeth—six on each side in the upper jaw, and five on each side in the lower jaw.
(ii) The tongue, lying between the halves of the lower jaw.