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Influence of Nervous System on* Cell life. 299 
another to activity, when an impulse has reached it from a 
nervous centre. 
Doubtless this phenomenon has many parallels in the 
body, and explains how remotely a nervous centre may 
exert its power. It enables one to understand, to some ex- 
tent, many of those wonderful co-ordinations (obscure in 
detail) which are constantly taking place in the body. 
We think the facts, as they accumulate, will more and 
more show, as has been already urged, that the influence of 
blood pressure on the matabolic (nutritive) processes has 
been much over-estimated. They are not essential, but con- 
comitant in the highest animals. 
Turning to the case of muscle, we find that when a skeletal 
muscle is tetanized, the essential chemical and electrical 
phenomena are to be regarded as changes differing in degree 
only from those of the so-called resting state. 
There is more oxygen used, more carbonic anhydride ex- 
creted, etc. The change in form seems to be the least im- 
portant from a physiological point of view. Now, while all 
this can go on in the absence of blood, or even of oxygen, it 
cannot take place without nerve influence or something sim- 
ulating it. F 
Cut the nerve of a muscle, ard it undergoes fatty degen- 
eration*and atrophy. True, this may be deferred, but not 
indefinitely, by the use of electricity, acting somewhat like 
a nerve itself, and inducing the approximately normal series 
of metabolic changes. If, then, the condition when not in 
contraction (rest) differs from the latter in all the essential 
metabolic changes in rate or degree only, and if the func- 
tional condition or accelerated metabolism is dependent on 
nerve influence, it seems reasonable to believe that in the 
resting condition the latter is not withheld. 
Certain forms of paralysis (e. g., hysterical) are not fol- 
lowed by atrophy. Why? Because in this form the meta- 
bolic nerve influence is still exerted. 
The recent investigations on the heart make such views 
as we are urging Clearer still. It is known that section of 
the vagi leads to degeneration of the cardiac structure. We 
