the sense organs with the central nervous system and the latter
with the muscles and glands. We have had to leave out of account
all discussion of the special functions of the cerebral cortex, thal-
amus, caudate nucleus, nucleus lentiformis, the cerebellum, and
the gray cellular masses in the brain stem. If what has been pre-
sented has been followed, the student should carry away with
him an increased knowledge of what kinæsthetic motor responses,
visual-motor responses, and organic-motor responses are, and
what is meant by the integration or tying together of long and
short reflex arcs in such a way that concerted, controlled and sus-
tained action in the muscles may be obtained. This knowledge is
fundamental if the factors underlying human behavior are sought.

The sympathetic system should not be confusing. Every
sense organ is the beginning of an arc which ends in a muscle.
The organic sense organ is no exception. The afferent portion of
this system is similar in all respects to that of the kinæsthetic or
cutaneous, but on the motor side it takes both the pre-ganglionic
neurone and the post-ganglionic (sympathetic) neurone to estab-
lish connections with the effectors. In other words, the pre-gan-
glionic neurone belonging to the central system has to be
"lengthened" or "supplemented" in order to reach and stimu-
late the motor organs belonging to the organic system. This is,
of course, an oversimplification in the interest of making the ana-
tomical relation clear. Whether neural action in neurones be-
longing to the sympathetic system is in all respects similar to
neural action elsewhere is a problem which we need not attempt
to study here.

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