Influence of the Nervous System 650 
rather infrequent and jerky voluntary movements were observed. 
Sixty-one days after the operation bothlimbs moved readily. ‘The 
explanation for the temporary paralysis of the one leg is found in 
the fact that the needle had penetrated that part of the cord whence 
the third plexus nerve on the right side takes its origin. ‘The injury 
is confined practically to the one side. ‘The cellular and fibrous 
layers and both the roots of this side are gone. ‘The abnormally 
large lumen is eccentric. Theinjury, though decreasing anteriorly, 
extends slightly beyond the origin of the second plexus nerve. 
Anterior to this level only secondary degenerative changes, to be 
later described, are found. 
In No. 1.37 the injury was far greater. Slight voluntary move- 
ments were not noted until 65 days after the operation. Examina- 
tion showed that the nerve cord had been completely destroyed in 
the tail and that part of the plexus region from which plexus nerves 
Il and III arise. Nerve I takes its origin in a very malformed and 
dilapidated cord, less than one-half its proper size, with the lumen 
in the form of a horizontal slit almost dividing the cord into an 
upper and a lower half, and the fibrous layer practically gone. 
We have here an example of the removal of the major portion of 
the cord from the plexus. The motor cells of nerves II and III 
were destroyed; most of the motor cells of nerve [ were also de- 
stroyed.- The surviving cells multiplied, grew together to form an 
irregular flattened ring, the cells of which supplied nerve I with 
some motor stimuli. Hence the vague movements of limbs after 
so long an interval. 
No. 1.7, first moved the rear limbs 42 days after the operation. 
Examination revealed conditions essentially like 1.37. 
No. 1.35 moved only after 125 days. Internally the injury and 
changes were like 1.37. 
No. 1.20. Rear limbs began to move “hesitatingly” 74 days 
after the operation. Preserved 19 days later. The result is 
instructive because it demonstrates that the nerve cord at so anterior 
a level as the plexus has the power to repair an injury and to prolif- 
erate cord cells to a limited degree. The cord was normal anterior 
to the origin of the first plexus nerve. Posterior to this level the 
cord had been severely injured. It is shruken to about one-half 
