s apparatus which produces muscular tone, and that it has much
analogy to the muscular phenomena of hysterical hypnosis, the genesis of
which is precisely explained by a functional hyperactivity of the nervous
centers of muscular activity. Until quite recently 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 macrosco