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710 the case than to any one symptom which may be presented by the injured person. The characteristics of the cases described by it indicate some functional or dynamic disturbance of the nervous equilibrium or tone, rather than structural damage to any organ. Another class of effects is included under the designation of fright neurosis or traumatic hysteria. The diagnoses of these phenomena are complemented by the citation of considerable numbers of cases which illustrate the almost capricious variety of the forms under which they are manifested. In treatment a pre-eminently important factor is rest; but, besides this general remedy, there are special forms of affection that require special applications. The mental condition is all-important; and in this connection special stress is laid upon the effect of the expectation of compensation, and upon malingering, into which the patient is to a greater or less extent seduced unintentionally and unconsciously by the trend of his thoughts and fancies; so that complete recovery is not assured till the mind is cleared, to which payment of damages contributes greatly; yet this is predicated without reflection on the character, motives, or entire honesty of the patient. The closing chapters are devoted to the discussion of this branch of the subject in its medico-legal aspects.

part of this excellent text-book treats of the physiology of the various senses, of that of certain special muscular mechanisms, as of the voice, of speech, and of looomotion; of the tissues and mechanisms of reproduction, including impregnation, menstruation, pregnancy, parturition, the phases of life, and death. Preceding the physiology of each organ there are descriptions of its anatomy and histology, as in the other parts of this work.

The great caution that Prof. Foster displays throughout the work in judicially presenting both sides of a moot point is well shown in the section on color sensations. Both the Young-Helmholtz and the Hering theory of color perception are explained, but the author is inclined to accept the latter, both because there is a recorded case in which only white and black could be seen, and because the phenomena of peripheral color vision better accord with Hering's theory.

In the chapter on hearing the author states that the exact nature of the process by which the vibrations of the perilymph, produced by waves of sound, give rise to auditory impulses is uncertain. Even accepting the theory that the basilar membrane may be considered as consisting of a number of parallel radial strings, each capable of independent vibrations, the other structures in the auditory epithelium present problems that are as yet unsolved; for the true function of the rods of Corti and of the reticulate membrane of which these form a part, of the cells of Deiters, and of the inner as distinguished from the outer hair-cells, are yet unknown.

The author considers, in the section on taste and smell, that certain recorded cases lead to the provisional conclusion that the gustatory fibers are fibers belonging to the fifth nerve, though they may reach the tongue partly by way of the glosso-pharyngeal, partly by way of the chorda tympani nerves.

While we agree with the author that cutaneous pain is a separate sensation, developed in a different way in the skin than is pressure or temperature sensation, we think that he should have laid stress on the latter as being developed in a different way than is pain or pressure sensation. In fact, recorded cases of nervous diseases suggest that, though correlated, the pressure, pain, and temperature senses are distinct entities.

He does not regard "muscular sense" as an appropriate term for the recognition of impulses that are derived not only from the muscular fibers, but also, and possibly to a large extent, from the tendons and other passive instruments of the muscles. Therefore this so-called muscular sense is the outcome of afferent impulses proceeding from the periphery and started in the parts concerned in the movement, and it should not be described by a term that implies a single source of the phenomenon.

The entire volume exhibits the same