ON THE THEORY OF GALVANOTROPISM 4458 
This reduplication of the secreting regions after the 
sectioning of the spinal cord is noticed not only immediately 
after severance of the cord, but at any time, even eight 
weeks after the operation—TI have not as yet studied these 
animals for a longer time than this—after the wound has 
FIG. 128 
healed so perfectly that it is impossible to recognize the 
position of the incision. These experiments render it very 
probable that the polar secretion of the glands of the skin, 
when a current is passed longitudinally through the animal, 
is determined by a stimulation of the central nervous system. 
FIG. 129 
It also seems as though the entire central nervous system 
behaves like a homogeneous whole, and as though the stimu- 
lation with a constant current occurs at the anode. 
3. In order further to test this possibility, I cut a number 
of Amblystome into small pieces. It was, of course, impos- 
sible to keep these pieces alive, so they had to be experi- 
mented upon immediately. In this way it was found that 
every piece of the animal which still possesses its correspond- 
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