Hall, G. Stanley. Adolescence. Its Psychology and Relation to Physiology, Anthropology, Sociology, Sex, Crime, Religion and Education. New

York, D. Appleton and Company, 1904. Vol. I. xx + 588, Vol. II, 784 pp. This work, by intent at least, is a biological psychology. The author has devoted many years to the study of various aspects of adolescence. During this time he has influenced and encouraged a great number of students in the investigation of problems of genetic psychology; unceasingly he has urged that "the studies of the mind need. new contact with life at as many points as possible." Instead of speculating concerning the future of the soul we should study its past, if we are desirous of understanding its present condition. "We must collect states of mind, sentiments, phenomena long since lapsed, psychic facts that appear faintly and perhaps but once in a lifetime, and that in only few and rare individuals, impulses that, it may be, never anywhere arise above the threshold, but manifest themselves only in automatisms, acts, behavior, things neglected, trivial and incidental, such as DARWIN says are often most vital. We must go to school to the folk-soul, learn of criminals and defectives, animals, and in some sense go back to ARISTOTLE in rebasing psychology on biology, and realize that we know the soul best when we can best write its history in the world, and that there are no finalities save formulae of development."

The work is much more than an assemblage of facts, for the author has convictions as well as ideas. His concern, as early appears, is with the bearing of his researches upon education. A few words from the introductory remarks will serve to indicate the practical trend and tone of the book. "Never has youth been exposed to such dangers of both perversion and arrest as in our own land and day. Increasing urban life with its temptations, prematurities, sedentary occupations, and passive stimuli just when an active, objective life is most needed, early emancipation and a lessening sense for both duty and discipline. . . . ." And again, "In education our very kindergartens

. tend to exterminate the naive which is the glory of childhood. Everywhere the mechanical and formal triumph over content and substance, the letter over the spirit, . . . . information over education, marks over edification, and method over matter."

The Psychology of Adolescence, as the book might be called, is full of the earnestness of purpose and enthusiasm of the author. Its facts are vitalized by the sense of contact with life which each page gives. President HALL has handled with admirable skill a subject which was at many points extremely difficult of treatment.

R. M. Y.

Davenport, C. B. The Collembola of Cold Spring Beach, with Special Reference to the Movements of the Poduridae. Cold Spring Harbor Monographs, II. 32 pp., I pl., 1903.

This is a description of the form, systematic relationships, habitat and modes of behavior of the simple insect Collembola. Apart from the new results of observation, which are interesting even to non-technical readers, the paper is valuable for its suggestions of methods and interests in the study of animals.

The spirit and purpose of the writer in his research can best be understood with the aid of the following paragraph from the monograph: "By this analysis I wish to enforce the idea that the movements of the podurids are not to be referred to so many 'volitional' acts; nor that, as instincts, are we to think of the tendency to particular kinds of behavior as having been inherited. But rather, the animal being provided with a sensitiveness of a certain sort to oxygen, to water, to currents of air or other movements, to contact, to gravity, and to light, it will behave on the beach as we see it behave there. Under another set of environmental conditions it will behave very differently. The movents of the podurids on the beach are the result equally of the specific, inherited capacity of response on the one hand and the particular stimuli afforded by the conditions of the beach."

And again, in a brief but effective summary the author thus states the chief matters of observation: "The podurids of the beach live between tide-marks, go into the sand at high tide and rise to the surface when the tide is out to take air. They run up surfaces in the face of the wind and leap when they reach the top, being blown back to the starting point. They are exceedingly sensitive to gravity, to contact, to moisture, to currents of air and to light, and these elementary reactions are so combined as to bring about their normal movements. They are provided with these instincts before they reach the beach. Had they not had such instincts they could never have lived on the beach. The instincts have selected the habitat."

R. M. Y.

Bigelow, Henry B. The Sense of Hearing in the Goldfish, Carassius auratus L. American Naturalist, 1904, 37, 275-284.

The experiments which form the basis of this paper were performed to test the accuracy of KREIDL'S conclusions, "that goldfishes do not hear"'—a conclusion reached after studying the sound reactions in fishes from which the semicircular canals with the attached parts had been removed.

The author first studied the reactions of normal fishes to sound vibrations and found that at least 78% of them gave definite well

marked reactions to such vibrations. He then studied the sound reactions of fishes on which various operations had been performed.

In one lot of fishes the skin was rendered insensitive by cutting the spinal cord and the lateral branches of the 10th, 7th and 5th nerves. The fishes with few exceptions recovered from the operations and many of them lived for weeks afterward. 80% of the animals with the nerves of the skin destroyed still gave normal reactions to sound vibrations.

In a second lot the ears were made insensitive by cutting the 8th nerves. This resulted in complete loss of response to sound vibrations. In a third lot the 8th nerve on one side was first cut in each fish. After this operation the fishes gave practically normal sound reactions, but after the nerve of the opposite side had been cut the fishes no longer responded to sound vibrations.

In a fourth lot the semicircular canals and attached portions of the ears were pulled out. After this operation, the fishes still reacted to sound, but the reactions were less marked in normal fishes.

The author thus repeated KREIDL's experiments and confirmed his results, but on dissecting these fishes he found that a portion of the ear largely imbedded in bone had not been removed. This portion he thinks probably represents the combinrd sacculus and lagena of higher vertebrates. It contains two otoliths and is well supplied with nerves from a branch of the 8th.

The experiments seem to show beyond a doubt, that the ear in goldfishes functions as an organ of hearing. A somewhat similar set of experiments, performed a year earlier by Dr. G. H. PARKER on Fundulus heteroclitus, led to the same conclusion with reference to that species. Dr. PARKER, however, was unable to note any reaction to sound vibrations in the smooth dog fish.

S. O. MAST.

Andrews, E. A. Breeding Habits of Crayfish. American Naturalist, 1904, 37, 165-206.

In this paper the author describes the habits of Cambarus affinis taken from the Potomac river. The habits of C. affinis are found to vary considerably from those of Astacus, the European crayfish. This fact lends additional interest to the observations of ANDREWS.

The most important points brought out in the paper may be briefly stated as follows:

Mating takes place during February, March and April, and sometimes in October and November. Each male may mate with more than one female. Sex union continues from 2 to 10 hours. The sperm is transferred to external seminal receptacles. The eggs are

laid at night, often not until "some weeks" after sexual union. After the eggs are laid the mortality is great among the females. It is, however, still greater among the males after sexual union, many dying immediately thereafter. Before the eggs are laid, the female thoroughly cleans her ventral surface. The eggs, from 400 to 600 in number, are fastened to the pleopods in clusters, much like bunches of grapes. Immediately after laying the eggs, the female seeks a dark place and there rolls from side to side, resting from 1 to 6 minutes on either side and on the ventral surface. This reaction continues for several hours and probably serves to fasten the eggs to the pleopods. Eggs removed from the female die unless the embryos in them are well developed. It requires from 6 to 8 weeks for the embryos to hatch, after which they remain attached to the mother continuously during the first week and part of the time during the second. After the second week they no longer return to the mother. If several mothers with embryos are in the same dish, the embryos frequently crawl onto the wrong mother. There is no evidence that the mothers recognize their own young. The embryos moult 2 days after hatching. The intervals between the following 5 moults vary from 5 to 18 days. Practically all the observations were made in the laboratory. It is to be regretted that more work was not done in the field. the descriptions are worked out in detail. These together with 10 very good figures convey a very clear conception of the habits studied and seem to show that the author made keen, thorough, careful observations. The literary merits of the paper, however, might have been improved by careful revision.

Most of

S. O. MAST.

Taverner, P. A. A Discussion of the Origin of Migration. Auk, 1904, 21, 322-333.

Return of birds to the winter home is easy, that to the summer home is hard, to explain. The author discusses previous theories, and concludes that sufficient emphasis has not been placed on the fact of the great increase in the bird population at the beginning of the breeding season. In southern latitudes some birds begin to breed early; when later breeders are ready to commence they find that food has become The scarcity of food thus brought about was, Mr. TAVERNER thinks, the chief cause of birds' having commenced the habit of seeking a new home at the beginning of the breeding season.

scarce.

WALLACE CRAIG.

Rawitz, B. Die Unmöglichkeit der Vererbung geistiger Eigenschaften beim Menschen. Biol. Centralbl., 1904, 24, No. 12, 396-408.

RAWITZ argues vigorously against the inheritability of mental traits in man. His standpoint is that of extreme materialism. G. W.