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only in so far as the two functions have as factors identical elements' (p. So). "Improvement in any single mental function need not improve the ability in functions commonly called by the same name. may injure it" (p. 91). There is no "general ability." Upon this the author repeatedly insists. The present reviewer thinks that Professor THORNDIKE Carries his idea of the independence of the mental functions to a point which threatens the unity of the mental life. One wonders how a mind such as the author describes ever could perform such a synthesis as that involved, for example, in writing book on Educational Psychology. He says that "the mind must be regarded not as a functional unit nor even as a collection of a few general faculties which work irrespective of particular material, but rather as a multitude of functions, each of which is related closely to only a few of its fellows" (p. 29). "The mind is really but the sum total of an individual's feelings and acts" (p. 30). "This view is in harmony with what we know about the structure and mode of action of the nervous system. The nervous system is a multitude of connections between particular happenings in the sense organs and other particular events in the muscles' (p. 30).

These unguarded statements surely must be accounted for as the result of a violent recoil from the extremes to which the "abstract psychological thinker" has carried the faculty psychology. It cannot be that Professor THORNDIKE means to deny the important structural and functional unities found in the nervous system and in conscious pro

cess.

Chapter X treats of "Changes in Mental Traits with Age,' and Chapter XI of "Sex Differences in Mental Traits." No mention is made of Professor HELEN BRADFORD THOMPSON'S recent work on "Psychological Norms in Men and Women." Chapter XII is on “Exceptional Children," especially defective children. A brief concluding chapter puts the "Problem of Education as a Science." An Appendix contains an "Index of Tests," of "Common Measures," and "Suggestions for Investigations in Educational Science."

The author is rather cavalier in his treatment of educational theory. But most of his readers will probably forgive him for that. As before remarked, the book is chiefly valuable as setting the task and suggesting the methods of a scientific study of education. It can scarcely be said that it adds much of positive value in the way of conclusions from data already studied. There are very few of the generalizations contained in this book which it would be safe to adopt without further vindication of their truth. But it certainly will stimulate more

exact methods of study of mental traits in relation to education, and this is more than justification for its appearance at this time.

H. HEATH BAWDEN.

Are Sounds, Made in the Air, Audible in the Water?

In their works on the sense of hearing in fishes and crustacea, KREIDL, BEER and PARKER have laid more or less emphasis on the reflection of sound waves in the air from the surface of the water. PARKER says (basing his statement to some extent upon experiment), "the plane separating air and water is, under ordinary circumstances, an almost impenetrable one for most sounds, whether they are generated on one side or the other of it, and many of the negative results obtained by previous investigators on the sense of hearing in fishes may have been due not so much to the absence of hearing in the animals experimented upon as to their inaccessibility to the sound, or at least to sound of an intensity sufficient to stimulate."

Interesting experimental evidence on this question is furnished by Dr. V. DUCCESCHI,' of Naples, in a recent number of the Rivista d'Itaita. Struck by the fact that some boys, diving along the shore, were able to repeat, on emerging from the water, the words called to them by their comrades while they were still beneath the surface, he secured the services of an expert diver, provided himself with a boat and some simple apparatus, and set out to test the matter experimentally. Trials were made at various depths up to seven meters. The length of time that the diver remained under water was about 10 seconds. At 5 meters the diver could hear distinctly, and repeat on coming to the surface, every word called to him from the boat. At 6 meters he could distinguish between the sounds of two glass bells of different sizes, a whistle and a small trumpet, all sounded in the air, could tell how many times each one was sounded, and in what order. At 7 meters the diver was able to distinguish the sounds with much less certainty, and sometimes not at all. The high tones were found to be much more difficult to distinguish than the low.

The same set of experiments was tried when the water was somewhat rough, with the result that the sounds were perceived with slightly less accuracy. It is true that in all these experiments the possibility of the sound being communicated through the boat to the water is not excluded. Moreover DUCCESCHI thinks it may be a question whether

IV. DUCCESCHI. Gli animali aquatici possiedono il senso dell'udito? Rivista d'Italia, Anno VI, pp. 958-966, Dec., 1903.

the sounds were perceived through the ears or through the bones of the head, as stopping the ears with vaseline did not seem to affect the perception. J. CARLETON BELL.

Edinger and Wallenberg's Bericht.'

We heartily welcome the appearance of this Bericht printed as a Separat of convenient form. Six hundred and twenty-eight titles are noticed in two hundred and seventy-two small pages. About one-tenth of the work is devoted to vertebrates below the mammals. The greater part of the whole work is now done by WALLENBErg.

Substitution of Function after Nerve Anastomosis.

J. B. J.

Some interesting side lights on the plasticity of the associational paths within the human cerebral cortex are thrown by a recent surgical case in which, after traumatic destruction of the facialis root and resultant paralysis, the central end of the spinal accessory nerve was sutured on to the peripheral facialis and a successful union effected. There resulted total permanent paralysis of the trapezius and sternomastoid muscles and almost perfect restoration of facial symmetry both at rest and (less perfectly) in the facial movements.

The account of the case is illustrated by numerous photographs taken before the operation for anastomosis and at various stages during the restoration of the function. The case brings into unusually sharp prominence the problem involved in the resultant alterations in the central associational paths and suggests a plasticity of cortical paths quite at variance with some of the current theories.

The Cerebral Commissures Again.3

C. J. H.

Professor G. ELLIOT SMITH takes as his text a remarkable aberrant commissure found only in the forebrain of Sphenodon and the true lizards and subjects the commissures of the hippocampal region of amniote vertebrates to a critical comparative examination. This aberrant commissure he finds to be "a bundle of fibers derived from

1 Bericht über die Leistungen auf dem Gebiete der Anatomie des Centralnervensystems in den Jahren 1901 und 1902. Von Prof. Dr. L. EDINGER und Dr. A. WALLENBERG. Leipzig, Verlag von S. Hirzel, 1903.

2 CUSHING, HARVEY. The Surgical Treatment of Facial Paralysis by Nerve Anastomosis. Annals of Surgery, XXXVII, 5, May, 1903.

3 SMITH, G. ELLIOT. On the Morphology of the Cerebral Commissures in the Vertebrata, with special Reference to an Aberrant Commissure found in the Forebrain of Certain Reptiles. Trans. Linn. Soc. London, 2 Ser., VIII, 12, July, 1903.

the caudal portion of the hippocampus, and therefore homologous (in part) with the psalterium of the Mammalia. But its behavior presents a marked contrast to that of the Mammalia: for, instead of pursuing an extensive forward course to cross over in the lamina terminalis, it avails itself of the primitive direct connection between the caudal lip of the cerebral hemisphere and the optic thalamus, and in this way reaches the roof of the third ventricle directly." Examination of certain amphibian brains leads the author to conjecture that here the aberrant commissure is represented, not in the dorsal commissure of the lamina terminalis, but in the superior commissure of OSBORN! Apparently there is here an interesting problem in cerebral morphology which remains to be worked out in the Ichthyopsida. C. J. H.

The Homologies of the Cerebellar Fissures.

Professor O. CHARNOCK BRADLEY attacks this intricate problem using a combination of the methods of comparative embryology and comparative anatomy, building upon the foundations laid by STROUD and KUITHAN. He recognizes that we must not begin by secking homologues of the human fissures in lower animals; but that, beginning with the smoothest and least complicated cerebellum, the fissural pattern should be worked out in the ascending series of mammalian complexity.

The paper opens with a description of the developmental stages of the cerebellar surface in the rabbit, after which comparison is made with other simple adult cerebella; viz., the hare, shrew, hedgehog, mole, rat, water-vole, bat and squirrel. The second part of the paper includes a similar description of the development of the pig, with comparison with the marten, badger, dog, fox, cat, goat, sheep, cow, horse and donkey. This is followed by a provisional application of the results to the subdivision of the human cerebellum in the light of the comparisons made. The paper is illustrated by numerous outline figures.

In a later paper Professor G. ELLIOT SMITH' controverts the author's position regarding the relations of the flocculus, paraflocculus and vermis, concluding that his views in this regard rest upon insuffi. cient data, in fact upon a (presumably anomalous) hare's brain and are

1 BRADLEY, O. CHARNOCK. On the Development and Homology of the Mammalian Cerebellar Fissures. Journ. Anat. and Physiol., XXXVII, Jan. and June, 1903.

2 Notes on the Morphology of the Cerebellum. Journ. Anat, and Physiol.. XXXVII,

July, 1903.

not consistent with the data of comparative anatomy generally. And this is followed by a more extended series of notes' supplementary to the same author's paper, "The Primary Subdivision of the Mammalian Cerebellum," in Journal of Anatomy and Physiology for 1902, and illustrated by a large number of figures, including a useful diagrammatic schema. C. J. H.

Mendel and Jacobsohn's Jahresbericht.2

The sixth issue of this admirable annual is similar in plan to its predecessors and equally indispensable. It contains 1333 pages, including 61 pages of author's and subject indexes.

Allis on the Anatomy of the Mackerel.3

C. J. H.

This splendid memoir (which has appeared as yet only as an author's separate) follows closely along the lines of the same author's well-known monograph on the cranial anatomy of Amia. In deed it dates from about the same period, having been finished and submitted for publication in July, 1899, and now published without alteration. It is characterized by the same accuracy, thoroughness and beauty of illustration and will doubtless prove a standard of reference for the teleost as the earlier work has done for the ganoid, though one cannot repress a shade of disappointment that it has not been possible for the author to revise the work at the time of publication so as to correlate the findings with the changed conceptions of cranial nerve morphology which the last five years have brought about. For instance, the full significance of the following criticism of GORONOWITSCH (p. 249) comes out much more clearly now, I opine, than when this was written in 1899: "That a careful study of the course and ultimate distribution of the cranial nerves of fishes can, in the present state of the literature of the subject, have but little morphological importance, and that all important results are to be obtained

1 SMITH, G. ELLIOT. Further Observations on the Natural Mode of Subdivision of the Mammalian Cerebellum. Anat. Anz., XXIII, 14-15, 1903, pp. 368-384.

2

Jahresbericht über die Leistungen und Fortschritte auf dem Gebiete der Neurologie und Psychiatrie. VI. Jahrgang. Bericht über das Jahr 1902. Berlin, S. Karger, 1903.

3 ALLIS, EDWARD PHELPS, JR. The Skull and the Cranial and First Spinal Muscles and Nerves in Scomber scomber. Reprint from the Journal of Morphology, XVIII, Nos. 1 and 2, April, 1903.

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