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Fig. 114.—The Lobes of the Right Side of Brain and their functions. (Jegi.)

The speech center is true only for left-handed persons. Medulla is marked "Bulb."

  • ments; that is, it makes the

muscles act at the right time and with due force in complex acts, such as standing, walking, talking. A man could strike just as hard without the action of the cerebellum, but he would not be likely to hit what he aimed at. A drunken man staggers and fails to control the muscles in walking because the alcohol has caused the blood to collect and congest around the cerebellum and press upon it. One whose cerebellum has been injured by accident staggers like a drunken man.

Fig. 115.—Motor and Sensory Areas of Left Hemisphere. Speech center marked "Lips."

In what region are the motor centers? The sensory centers?

Coverings of the Brain.—Lining the skull and covering the cerebrum are found two membranes which inclose a lymph-like fluid. Thus a kind of water bed is made which surrounds the soft and delicate cerebrum and protects it from jars. A