Influence of the Nervous System 669 
TABLE 2 
Paralyzed limbs amputated a second time 
| 
| DAYS AFTER FIRST | DAYS AFTER IDAYS AFTER SECOND, DAYS AFTER 
se | AMPUTATION | PARALYSIS | AMPUTATION PARALYSIS 
| | 
1.36 110 110 53 | 163 
1.40 147 | 157 | 34 | 188 
1.43 50 | 108 | 72 | 180 
1.45 | 100 | 140 54 194 
5-4 154 130 | 36 166 
1.42 | 84 | 110 145 | 250 
| | 
Other Attempts to Prevent Regeneration 
Though not directly connected with the main issue, these experi- 
ments are perhaps of sufficient interest to warrant their insertion at 
this place. The effort was made to prevent the regeneration of the 
leg by the removal of some other non-nervous tissue. Tornier 
had found that lack of growth of the skeleton of the tail in sala- 
mander prevented further growth of the tail. Morgan observed 
that the removal of the notochord in frog tadpoles inhibited the 
regeneration of the tail. These observations suggested the 
removal of the bone in the leg. ‘This was done in two ways. In 
the first place a piece of the femur about 2 mm. long was cut out 
from the amputated end. ‘The distal part of the limb disintegrated 
and regeneration began at the more proximal level where all the 
tissues were intact. In the second place, a piece of the bone was 
removed from the middle of the femur, in the belief that regenera- 
tion might be inhibited until the two pieces grew together. But 
here too the peripheral end sloughed off, or disintegrated down to 
the level at which all tissues were present and continuous, whence 
regeneration began. In another group the leg was cut in such a 
manner that the femur protruded beyond the rest of the leg about 
Ito14 mm. Again the bone disintegrated to the level of the other 
tissues, then regeneration began. 
We may refer here once more to Wolff’s experiments. Wolff 
does not state explicitly how much of the nerve cord and dorsal 
ganglia were destroyed in each animal. Subsequent sensory and 
