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upon Vital Staining, by S. J. MELTZER. A single ligation of a nerve has no influence upon the staining of the nerve on either side of the ligature. When, however, two ligatures are applied, the section of the nerve between the ligatures remains free of color, while both ends are stained. This is the case, even if the section between the ligatures comprises nearly the entire length of the nerve.

The Effect of a Subcutaneous Injection of Adrenalin on the Eyes of Cats whose Sympathetic Nerve is Cut, or whose Superior Cervical Ganglion is Removed, by S. J. MELTZER. When the sympathetic is cut, a subcutaneous injection of adrenalin causes a retraction of the nictitant membrane, and no change is seen in the size of the pupil or the width ‘of the palpebral fissure. When, however, the superior cervical ganglion is removed, an injection causes a strong dilatation of the pupil, a considerable widening of the palpebral fissure, and a retraction of the nictitant membrane.

The Delineation of the Motor Cortex in the Dog, by H. CUSHING.

Demonstration of Expressive Motions in a Decerebrate animal, by R. S. WOODWORTH.

At the meeting of the American Philosophical Association at Princeton the paper, "An Establishment of Association in Hermit Crabs," by EDWARD G. SPAULDING, which we publish herewith, was read. There was one paper on comparative psychology read at the meeting of the American Psychological Association at St. Louis.

A Preliminary Paper on the Psychology of the English Sparrow, by JAMES P. PORTER. Experiments were made with the food box, with SMALL’s complex maze and in other ways to determine the method of approaching the food, to investigate the so-called senses of number and of direction and the color preferences.

A paper was read before the section of physics of the American Association at St. Louis, which is of some interest to physiologists, especially when taken in connection with the physiological experiments of Nagel on the rate of diffusion of odors and savors in water.

The Rate of Propogation of Smell, by John ZELENY. Attention is drawn to the extreme slowness of diffusion of odors in air tubes where convection currents are avoided. The time required for the diffusion of odors is roughly proportioned to the square of the distance.

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LITERARY NOTICES.

Animal Education,

Under this title Dr. Watson has published the results of a study of the white rat made for the purpose of correlating the psychical development with the growth of the nervous system. The work is naturally divided into three parts: (1) an experimental study of the psychical development; (2) an histological study of the central nervous system, for the purpose of tracing the development of medullation, and (3) a correlation of the psychical facts with the neurological facts.

Part I. The ability of the white rats at different ages to form simple associations was tested by various forms of the labyrinth method. The obtaining of food was employed as a motive. Usually the food was placed in a box and the animals were given a chance to get it by finding a hidden opening into the box, by opening a spring door, or by wending their way through a labyrinth. The observer watched the behavior of the animals, and recorded the time required for the accomplishment of a given act. The results of this psychological study include certain interesting points of difference between young and mature rats which cannot be better stated than in the words of the author :

No form of problem which the adult rat is capable of solving presents insurmountable difficulties to the rat of twenty-three days of age.

2. a) The time of first success in solving problems conditioned chiefly upon physical activity is shorter for young rats than for adults.

b) For the second solution of such a problem, adult rats do not require a longer time than young rats.

c) Problems not so conditioned upon physical activity are solved, even the first time, more quickly by adult than by young rats.

3. a) Young rats make many more useless movements than adult.

1.

:

1 Watson, John B. Animal Education: An experimental sturdy on the psychical development of the white rat, correlated with the growth of its nervous system.

Chicago, The University of Chicago Press, 1903, 122 pp., 22 Figs., 3 Plates.

b) After once associating the various parts of a problem, adult rats make only the movements necessary to attain the desired end, while young rats-owing to their superabundant physical activity and lack of muscular control-continue to make useless movements long after adult rats have discarded them entirely.

c) There is a gradation in the number of useless movements made by rats at different ages. At thirty-five days of age, when physical activity appears to have reached its highest stage, the percentage of useless movements is largest. As the rats grow older this superabundant activity disappears, and in its place comes direction of activity.

Concerning the stages of memory the author writes :

1. Until the rat has reached the age of twelve days, life to it is simply a matter of pure instinct. Certain movements are made, but these movements are dependent upon the ready-made adjustments of neural and motor elements with which the rat begins life ; intelligence plays little or no part.

2. At twelve days of age memory is present in a simple form.

3. From the twelfth to the twenty third day there is a gradual but rapid increase in the complexity of the memory processes until at the latter age psychical maturity is reached. Development after this age is analogous to the development that takes place in a child of ten years as he għadually becomes more and more mature.

Parts II and III. Having investigated the capacity of rats to learn simple associations, at different stages of development, the author proceeded to make a careful histological study of the changes which occur in the nervous system from birth to maturity in order that he might be able to correlate the psychical and neural conditions and definitely determine whether associations are dependent upon the medullation of nerve fibers. As a result of this work Dr. Watson concludes: (1) that the “medullated fibers in the cortex of the rat are not a conditio sine qua non of the rat's forming and retaining definite associations, and (2) that the complexity of the psychical life increases much more rapidly than does the medullation process in the cortex, psychical maturity being reached when approximately only one-fifth of the total number of fibers in the cortex are medullated.”

Instead of speculating about the general significance of medullation the author very wisely confines himself to the discussion of his own particular facts. The experimental work is clear cut and decisive, and if one sometimes feels that fewer words might have sufficed and and space been saved by the condensation of results into tables, the excellent summaries more than compensate for the lengthiness of the descriptions. Dr. Watson has done a valuable piece of work in a field which has been open thus far for the theorizing of neurologists and psychologists.

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ROBERT YERKES.

Metaphysics in Comparative Psychology.'

The first of these articles is a defence of the comparative method in psychology in general, but more particularly when based upon an identity theory of the relation of brain and consciousness. He criticizes that school of comparative psychologists which attempts to reduce all forms of animal reactions to the type of mechanical tropisms, asserting that this tendency toward a mechanical interpretation is the direct product of false metaphysical assumption - that of psychophysical parallelism. Instead of this, the author upholds a theory of identity which makes it possible for him to put "Seele" in parenthesis after “Gehirn."

The arguments with which he attacks the parallelistic doctrine are familiar enough and will perhaps pass muster; at least they are the usual arguments wielded in current controversy. On a parallelistic hypothesis, when the one series is complex, the other should be complex, and vice versa : but this is not the case. The psychical sequence, which, on the parallelistic theory, ought to form a continuous whole is arbitrarily broken without any assignable cause, or the psychological causes which are assigned prove, on closer inspection, to be inadequate. Both of these arguments, in the opinion of the reviewer, can be met by the parallelist. But let it pass. More important for criticism are the positive arguments brought forward in support of the identity doctrine.

The author points out that there are important brain centers which are inaccessible to present physiological experimentation and which seem to bear no direct relation to our ordinary consciousness. Consciousness corresponds to a comparatively limited phase of cerebral activity. Indirectly, however, the content of consciousness is influenced to a high degree by the activities of these centers. It is not astonishing, therefore, that the psychophysical law does not hold. (He does not say so, but presumably this is because of the inhibitory effect of competing stimuli originating in these centers.)

Instead of regarding this as evidence simply of an unsuspected complexity in the conditions of that shifting area of tension which con

TA. FOREL. Die Berechtigung der vergleichenden Psychologie und ihre Objekte. Journal für Psychologie und Neurologie, Band I, Heft 1 und 2, pp. 3-10 (1902); Beispiele phylogenetischer Wirkungen und Rückwirkungen bei den Instinkten und dem Körperbau der Ameisen als Belege für die Evolutionslehre und die psychophysiologische Identitätslehre. Ibid., Band I, Heft 3, pp. 99110 (1902); Ants and Some Other Insects, Monist, Vol. XIV, No. 1. Oct. 1903 ; Jan. 1904. Tr. by W. M. WHEELER.

stitutes consciousness he, however, regards it rather as evidence of an infra-consciousness corresponding to, or rather he would say, constituting these inaccessible cerebral activities. What more natural than to assume, he says, that every cerebral activity has its introspective or inner counterpart, if not in our ordinary upper consciousness, then in this lower consciousness. Here is the key to the author's point of view and to his identity theory, and the reader who has already threshed out the problems here involved will doubtless turn to more instructive reading. There is no fallacy which to a greater extent vitiates the arguments ordinarily brought forward in support of this theory than the doctrine of subconscious mental states.

Under cover of this concept of a lower consciousness, the author finds it possible to attribute, not only consciousness but in some cases a high degree of consciousness to the lowest types of animals, e. g., to the Arcellae described by ENGELMANN. He finds evidences of memory, perception, association, feeling, choice in ants and bees. He says that the domestication of certain insects proves their plasticity, and finds evidence of this trait even in worms and echinoderms. Obviously, the significance of such statements must be interpreted in terms of his theory of unconscious mind.

His second article treats more in detail of the habits of various species of South American ants—which, again, he makes corroboratory of his identity doctrine. That there is truth in some form of the identity theory is extremely probable. One will perhaps agree with the author when he says that logically there is no more direct connection between my individual psychology and your individual psychology than there is between my individual psychology and the physiology of

Hence actions, gestures, movements, attitudes, are significant for psychology as sense-impressions. Human psychology is, and must be, comparative psychology.

But when he says that environment influences brain (soul) through the sensory nerves, and brain (soul) influences the muscles, glands, etc. (and thus the environment) through the motor nerves, one begins to feel that the meanings of words are becoming confused. And this feeling is increased when he adds that the soul is the brain-activity reflected in consciousness. One suspects that the concept

of a lower consciousness is simply a screen behind which the author may slip unnoticed from one meaning of a word to the other according to the exigencies of the argument.

But quite apart from this, it must be remembered that the brainactivity, which the author identifies with the soul-activity, cannot be

my brain.

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