second (for the centrifugal), and in the hypoglossus nerve 10.5 m. per second, (3) observation that the brain is able to execute apparently conscious functions at least two and a half hours after separation from the spinal cord.

R. M. Y.

Kiesow, F. Contribution à l'étude dela vélocité de propagation du stimulus dans le nerf sensitif de l'homme. Archives Italiennes de Biologie, t. 40, pp. 273-280, 1903.

By carefully measuring the reaction-time of thoroughly trained subjects to tactual stimuli applied at different regions of the arm or leg KIESOW has succeeded in showing to his satisfaction that the rate of transmission in the sensory nerves of man is practically the same as for the motor nerves, 30 to 33 m. per second.

The work is very clean cut, and the results are so uniform that one cannot doubt the truth of the author's conclusions.

R. M. Y.

Motora, Yujiro. A Study on the Conductivity of the Nervous System. Amer. Jour. Psy., Vol. 14, pp. 329-350, 1903.

This is a brief discussion of theories of nerve conduction, and a description of certain experiments upon which the author bases his so-called hydraulic theory.

For the facts of nerve transmission, he writes: "I propose an hydraulic explanation. It supposes that nervous conduction is a transmission of a water wave in a protoplasmic tube and that the protoplasmic tube not only helps the transmission by its own elasticity but is excitable at any point by means of a stimulus directly applied to it."

MOTORA experimented with water-filled tubes under various conditions to determine whether the phenomena characteristic of nerve conduction are exhibited also by them. The experiments deal with the following topics: Experiment 1-Rate of transmission of water wave in rubber tubes. It was found to be about 100 feet per second, or approximately the same as the nerve rate. Experiment 2-Evidence of an action current. Under certain conditions, we are told, the wave in a tube filled with slightly acidulated water is accompanied by what appears to be a thermo-electric current. The author writes concerning the action current in the nerve, "I believe that the action current is explicable as a thermo-electric current produced between two points of the nerve where the electrodes touch it." Experiment 3 -Inhibition phenomena. This study of the interference of water waves leads the author to the conclusion that the phenomena of attention and inhibition "are very conveniently explained under the supposition of a protoplasmic tube" (filled with fluid).

Although the paper yields no definite results so far as our knowledge of the nature of the nerve impulse is concerned, it contributes several curiously interesting facts, and a few analogies of problematic value.

R. M. Y.

Lillie, Ralph S. The Relation of Ions to Ciliary Movement. Amer. Jour. Physiol., Vol. 10, pp. 419-443, 1904.

Gowers, William R. Subjective Sensations of Sight and Sound, Abiotrophy, and other Lectures. Philadelphia, P. Blakiston's Sons & Co., 1904. This is a collection of lectures mostly published before, but well worth having united in book-form, and carefully revised.

The lecture on subjective visual sensations limits itself largely to the conditions in migraine, epilepsy; the one on subjective sensations of sound to the various forms of tinnitus. As such they form an interesting supplement to any chapter of hallucinations.. A note (p. 9095) is a plea to change the accepted form of designating musical notes as C, C, C, C C1 C2 C3 C1 C3 C3, which gives the "neutral C" to the middle C between the bass and treble staves, and has some mnemotechnical advantages concerning the number of vibrations (C=33; C1=66; further C' the first number with four figures, i. e. 1065, and C-4224).

The lecture on Abiotrophy; (diseases from defect of life) introduces a new term for deficiency of vitality of special tissues and parts of tissues: skin, baldness, muscles, nervous system, etc., and the supplementary interstitial overgrowth, either as deficent constitutional endowment, or as such defect brought on through toxic and toxinic factors with selective degenerations. Leture IV, on Myopathy and a Distal Form, deals with an important type of this group.

The remaining lectures, on Metallic Poisoning, Syphilitic Diseases of the Nervous System, Inevitable Failure (a study of syphilitic arterial disease), Syringal Haemorrhage into the Spinal Cord, Myasthenia and Ophthalmoplegia, and the use of drugs, are probably of more exclusively medical interest.

It is to be regretted that the "Dynamics of Life" are not included in this collection.

A. M.

Bourneville. Recherches et Therapeutiques sur L'Epilepsie, L'Hysterie et L'Idiotie. Vol. 23, Paris, Félix Alcan, 1903.

This Annual Report of the Institution at Paris is followed as usual by the study of a number of cases: The Mongolian type (with histological examination of two brains); the role of alcoholism in the production of idiocy, etc. This is the 23d Volume of a very creditable

series.

A. M.

Raymond, F. and Janet, Pierre.
II. Paris, Felix Alcan, 1903.

Les Obsessions et la Psychasthénie, Vol.

This second volume of the very interesting work of Professor JANET brings the clinical material underlying and further illustrating the discussions of the first volume. It is a treasure of clinical information, full of masterly descriptions and analyses. The whole work is a remarkable continuation of the similar set of two volumes-"Névroses et idées fixes." A. M.

Mills, Wesley. The Neurones and the Neurone Concept Considered from the Anatomical, Physiological, Pathological and Psychological Point of View. Montreal Medical Journal, Dec., 1903.

An illustrated summary of the leading facts on which the neurone doctrine is based, occupying 22 pages.

C. J. H.

Dogiel, A. S. Ueber die Nervenendapparate in der Haut des Menschen. Zeits. f. w. Zool., Bd. 75, H. 1, pp. 46-111, Pl. IV-XIV, 1903. Methylene blue method. An important histological paper.

J. B. J.

Hübschmann, Paul. Untersuchungen über die Medulla oblongata von Dasypus villosus. Zeits. f. w. Zool., Bd. 75, H. 2, pp. 258-280, 1903.

J. B. J. Marenghi, Giovanni. Alcune particolarità di struttura e di innervazione della cute dell'Ammocoetes branchialis. Zeits. f. w. Zool., Bd. 75, H. 3, pp. 221-429, 1903.

The author finds by the GOLGI method, in addition to the free nerve endings already known, sense cells in the epidermis which give rise to centripetal fibers. The reviewer has studied the same structures, which are frequently impregnated in his preparations of Lampetra, and has come to the conclusion that they are ordinary epidermal cells, the precipitate upon which is continuous with that upon neighboring free nerve fibers.

J. B. J.

Comparative Neurology and Psychology

Volume XIV

1904

Number 3

AN ENUMERATION OF THE MEDULLATED NERVE

FIBERS IN THE VENTRAL ROOTS OF THE

SPINAL NERVES OF MAN.

By CHARLES E. INGBERT.

(From the Neurological Laboratory of the University of Chicago).

III. Determination of the areas of the cross-sections of the ventral roots of the spinal nerves of man.

IV.

Determination of the number of nerve fibers in the ventral roots of the spinal nerves of man.

3. Comparison of STILLING'S estimate with the author's enumeration.

V. The number of nerve fibers per square millimeter of the cross-section of the ventral roots of the spinal nerves of man.

I.

Determinations and comparisons.

2. Discussion of Figure 3.

VI. Relation between the ventral and dorsal roots.

Relation of areas of cross-sections.

VII.

I.

4.

5.

Comparison of the ratio of the number of nerve fibers in the ventral and the dorsal roots of the frog, of the rat, and of man.

Relation of small and large fibers.

On the relative area of the cross-section of the roots forming the brachial and lumbo-sacral plexuses in the male and the female.

I. Introduction.

Having completed "The Enumeration of the Medullated Nerve Fibers in Dorsal Roots of the Spinal Nerves of Man" (June, 1903), the author attempted to determine how many of these dorsal root fibers innervated the muscles and other deep tissues, and how many, the skin. For this purpose it was necessary first to determine the number of nerve fibers in the ventral roots. This was done. Using the number obtained in this enumeration, an estimate was made "On the Density of the Cutaneous Innervation in Man" (October, 1903).

The purpose of this present paper is to give in detail the results obtained from the study of the number of fibers in the ventral roots.

II. Historical Statement.

Although estimations of the number of medullated nerve fibers in different spinal and cerebral nerves of man and determinations of the areas of their cross-sections have been made by D. ROSENTHAL (1845), STILLING (1859), TERGAST (1872), KUHNT (1879), W. KRAUSE (1876 and 1880), SALZER (1880), and VOISCHVILLO (1883), no complete count of the spinal nerves had been made prior to the author's observations cited above (June, 1903). We are now able to add a similar enumeration of the medullated nerve fibers in the ventral roots of the spinal nerves of the same man. For a description of the material, the reader is referred to the paper first mentioned above.

III.

I.

Determination of the Areas of the Cross-Sections of the
Ventral Roots of the Spinal Nerves of Man.

Kölliker's Determination.-Under conditions which have been described elsewhere in detail (INGBERT, June, 1903, p. 55), KÖLLIKER (1850, p. 434) determined the area of all the cross-sections of all the ventral roots of the left spinal nerves

1 KÖLLIKER does not give the areas of the ventral roots of the sacral nerve IV and V. We estimate their combined area as about 0.2 mm2 and have corrected his results by adding this amount.