it was supposed that the rhythmical action of the heart was entirely due to the periodical and orderly discharge of motor nerve force in the nerve ganglia which are scattered through the organ; but recent physiological observations, more especially the brilliant researches of Graskell, seem to show that the influence of the cardiac ganglia is not indispensable, and that the muscular fiber itself, in some of the lower animals, at all events possesses the power of rhythmical contraction.

Several valuable additions to our knowledge of the anatomy of the nervous system have been made by Huschke, Exner, Fuchs, and Tuczek.

Tuczek and Fuchs have confirmed the discoveries of Exner, that there are no medullated nerve fibers in the convolutions of the infant, and Flechzig has developed this law, that “medullated nerve fibers appear first in the region of the pyramidal tracts and corona radiata, and extend from them to the convolutions and periphery of the brain,” being practically completed about the eighth year.  This fact is of practical importance in nervous and mental diseases, since it is becoming an admitted truth that the histological changes in disease follow in an inverse order the developmental processes taking place in the embryo.  Hence the recent physiological division of the nervous system by Dr. Hughlings Jackson into highest, middle, and lowest centers, and the evolution of the cerebro-spinal functions from the most automatic to the least automatic, from the most simple to the most complex, from the most organized to the least organized.  In the recognition of this division we have the promise of a steadier and more scientific advance, both in the physiology and in the pathology of the nervous system.

Mr. Victor Horsley has recently demonstrated the existence of true sensory nerves supplying the nerve trunks of nervi-nervorum.

Prof.  Hamilton, of Aberdeen, claims that the corpus callosum is not a commissure, but the decussation of cortical fibers on their way down to enter the internal and external capsules of the opposite side.

Profs.  Burt G. Wilder, of Ithaca, and T. Jefrie Parker, of New Zealand Institute, have proposed a new nomenclature for macroscopic encephalic anatomy, which, while seemingly imperfect in many respects, has, at least, the merit of stimulating thought, and has given an impulse to a reform which will not cease until something has been actually accomplished in this direction.  The object being to substitute for many of the polynomial terms, technical and vernacular, now in use, technical names which are brief and consist of a single word.  This has already been adopted by several neurologists, of whom we may mention Spitzka, Ramsey, Wright, and H.T.  Osborn.

Luys holds that the brain, as a whole, changes its position in the cranial cavity according to different attitudes of the body, the free spaces on the upper side being occupied by cerebro-spinal fluid, which, obeying the laws of gravity, is displaced by the heavier brain substance in different positions of the body.