rtain
want of co-ordination in the movements has been noticed in the early
stage of paresis, and the peculiar staggering walk of persons in this
stage is probably owing to an affection of the motor-centres of the
cerebellum. That they do not escape the action of the subtle poison,
when symptoms denoting the invasion of all the other motor-centres
throughout the body are in evidence, we have every reason to assume.
The co-ordination and automatic regulation of the lower motor-centres
must necessarily escape observation when the function of these centres
is partially suspended, and when, moreover, the powerful currents of
nerve force the cerebellum and basal ganglia receive from the motor
cortical centres of the cerebrum are partially if not wholly withdrawn.

E. Action of the Motor Cortical Centres of the Cerebrum.

In all but the very lightest cases of snakebite-poisoning there are
always symptoms manifested that cannot be referred to any other cause
than an invasion of the centres now under consideration. They range from
mere stupor, confusion of thought and delirium to the deepest coma, with
complete extinction of consciousness and insensibility to all external
impressions. Coma is a frequent and in serious cases an almost
invariable symptom in Australia. After the bite of our death adder only
we find persons sometimes collapse and expire suddenly, when still
conscious and able to answer questions rationally. Coma invariably
develops from sleep. It is, in fact, sleep intensified. An almost
irresistible desire to sleep is one of the first symptoms to be
observed. If the dose of poison imparted by the snake has been small,
the desire may pass off or the sleep may not assume the form of coma,
but in all serious cases it quickly assumes that form. _Vice versa_ the
deepest coma becomes sleep again, when the suspended function of the
cortical centres is roused by strychnine injections. The insensible and
completely paralysed patient usually announces the gradual return of
consciousness by a few groans and uneasy movements and not unfrequently
begins to snore, as in ordinary sleep, when a smart shake at the
shoulder will rouse him into full consciousness. At other times this
transition from coma back to sleep does not take place and consciousness
returns quite suddenly, the persons opening their eyes and looking
around them, dazed and bewildered, but perfectly conscious at once. When
coma is fully established and the larg