body, a fiber called the axone ending in fibrils called the endbrush. (Norsworthy and Whitley.)

NEUROTIC. Predisposed to nervous disorders.

NOMADISM. The wandering impulse, a fundamental human instinct. OBLIVISCENCE. Forgetfulness.

ONTOGENETIC. Pertaining to the development of the embryo or the individual.

ORIENTATION. The localization of objects in imagination either with reference to one's self, or to one another, or to fixed, standard directions. (Freeman.)

OVUм. The egg. A female germ cell.

PAIDOLOGY. The science of the child. (Oscar Chrisman.)
PARANOIA. A mental disorder characterized by systematic de-
lusions of persecution.

PATHOLOGICAL. Pertaining to disease.
PERCEPT. Sense consciousness.

PERCEPTION. A sensation which has acquired a meaning through its combination with other sensations. (Freeman.)

PHOBIA. An unreasonable fear or anxiety, such as the fear of open spaces, the fear of closed spaces, etc. A persistent, unreasoning fear of some object or situation.

PHYLOGENETIC. Pertaining to the evolution of the species. PLATEAU. A place in the practice curve more or less on the dead level, representing lack of measurable progress.

PLAY. An activity which, from the point of view of the observer, meets no need except that of the development; and from the point of view of the one who plays, is carried on entirely for its own sake and not for the sake of the results. (Freeman.) PREPARATORY REACTIONS. Reactions only "mediately of benefit to the organism, their value lying in the fact that they lead to, and make possible, a consummatory reaction." (Woodworth.) PROBLEM. A question involving doubt. (Webster's Dictionary.) PROJECT. A wholehearted purposeful act carried on amid social surroundings. (Kilpatrick.)

PROPHYLAXIS. Prevention of disease.

PSEUDO-FEEBLE-MINDEDNESS. A mental condition that is not feeblemindedness but simulates it.

PSYCHIATRY. A branch of medicine relating to mental disease. PSYCHOANALYSIS. A method of treating functional mental disorders by analyzing the mental content.

PSYCHONEUROSIS. A nervous disorder involving special mental symptoms.

PUBERTY. The age of sexual maturity.

PUPIL-PROJECT. A unit of practical activity planned by the pupils. (Parker.)

REFLEX. The mechanical response of a muscle or gland to a definite sensory stimulus.

A definite response to a definite stimulus, due to an inherited arrangement of nerve paths,

REFLEX ARC. The nervous path of a reflex action from the sensory area of stimulation to the center and out again to the muscle or gland.

REFLEX CIRCUIT. A reflex arc plus the return path leading from the muscle back to the central part of the circuit. (Freeman.) REFLEX THOUGHT. Active, persistent, and careful consideration of any belief or supposed form of knowledge in the light of the grounds that support it, and the further conclusions to which it tends, constitutes reflective thought. (Dewey.) REGRESSION, LAW OF. If parents in a given population diverge a certain amount from the mode of the population as a whole, their children, while tending to resemble them, will diverge less from the mode.

REPRESSION. Expulsion from consciousness of a pain-provoking mental process. (Jackson.)

SENSATION. A simple experience which is produced by the stimulation of one of the sense organs. (Freeman.)

SENSE ORGANS. Specialized nerve endings or structures in the body which are sensitive to various kinds of stimuli.

SENSORI-MOTOR ACTIVITY. One which consists in the adaptation of a movement to a stimulus. (Freeman.)

SKILL. A complex of simple habits, used with greater consciousness of the end in view.

SOMA. A term applying to the body as distinct from the germinal substances.

SOMATIC. Pertaining to, or arising from the body.

SPERMATOZOON. The male element in the process of fertilization. SPLANCHNIC NERVES. A group of nerve fibers of the sympathetic system that supply the viscera.

STIMULUS. Any object or any occurrence which may affect an individual's sense organs and arouse within him a sensation, idea, or movement-that is, any form of response. SUBLIMATION. The process of deviating sexual motive powers from sexual aims to new aims other than sexual.

(Brill.)

Changing the emotion connected originally with an instinctive response so that it is felt in other situations. The act of diverting the lower or more "brute-like" instinctive tendencies into higher levels of expression.

SUBSTITUTION. Changing the instinctive reaction to a situation. SUGGESTION. A proposition to action which is brought to the mind in such a way that the idea of the opposite action is more or less suppressed is called by the psychologist a "suggestion." (Münsterberg.)

SYNAPSE. The surface of contact between the axon of one neuron and the dendrites of another, at which the nerve current passes over from one neurone to another.

THINKING. A process of comparing, deliberating, or weighing possibilities and coming to a decision. (Bolton.)

TONUS. A condition of tension that keeps a muscle more or less moderately stretched and ready for action.

TOXIN. A poison usually of metabolic, bacterial, or vegetable origin.

TRIAL AND ERROR, OR TRIAL AND SUCCESS. A method of learning in which successive attempts are made with no clear idea of their value or probable result. A method of learning in which one learns to make an adjustment not by studying the problem which is presented, but by attacking it more or less blindly and then gradually eliminating the unsuccessful and retaining the successful trials.

UNCONSCIOUS. Mental processes which cannot be brought to consciousness without external aid.

UNIT-CHARACTER OR UNIT-FACTOR OR GENE. Such characters of animals and plants as are inherited as independent units. VISCERA. Organs contained in the body cavities.

VOLUNTARY ATTENTION. Attention given with a feeling of effort. WILL. The whole mind active. (Angell.)

The sum total of all the tendencies, inherited and acquired, that determine our actions. (Titchener.)

WORK. Activity, whether pleasurable or not, which is carried on primarily to attain some desired end. (Freeman.)

INDEX