Influence of the Nervous System 681 
TABLE 3 
Regeneration of tail in Diemyctylus viridescens 
| LENGTH OF | 
No. | EVEL OF | corp RE- | TIME | TAIL REG. NERVE CORD REG. 
| AMPUTATION 
MOVED 
| mm days mm mm 
16.14 middle 4 60 | 43 84 
15.6 | middle | BPN Sb. 1) Cae 74 
1.4 posterior 4 | 67 3 7 
15.1 middle 4 78 | 5 9 
1.9 posterior 34 | 124 24 6 
T25: |/ middle. | ® | aga | 14 64 
1.8 | anterior 4 170 | 6 10 
15.4 ? 8 59 | Dia 10 
14.21 posterior 8 74 3 Il 
1.15 ? 8 126 + 8+ 
15.4 8 72 I 9 
16.10 middle 4 61 ° To amputated end 
16.9 4 61 ° To amputated end 
16.2 middle 4 92 ° Almost to amputated end 
16.8 4 45 ° Within 2 mm. of amputated end 
I.11 | posterior 4 32 ° Within 14 mm. of amputated end 
1.1B | anterior 4 30 ° No regeneration. Reparative 
| changes only 
14.1 104 177 ° Iomm., i. e., 4 mm. from end 
14.18 posterior 7 124 ° 6 mm., i. e. 1 mm. from end 
14.8 _ middle 114 156 ° 1mm. Double cord 
14.14 posterior 7 36 ° I. mm. 
TA | 12 | 38 ° | Reparative changes Double cord. 
1.19 9 17 ° | ° 
etc. ° ° 
Cord Prevented from Reaching the Cut Surface 
The matter was experimentally tested in the following manner. 
After removing 2 mm., or less of the nerve cord, the end of the 
neural tube was closed with a plug of paraffin or celloidin. 
Sometimes a flap of skin, like that of a pocket, was sewed over the 
wound to prevent the plug from falling out. [n this experiment 
only a small part—if any—of the nerve supply to the amputated sur- 
face was destroyed. ‘The elapsed time was more than sufficient 
to allow even severely injured animals to regenerate, viz: 204 days, 
