m 



RATE OF REGEXERATIOX—ZELEXY 



77 



The lengths regenerated during the first four days are respectively 

 0.27. 0.15, 0.51, 0.45, 0.46 and 0.51 for the six levels. There is no 

 regular increase with removed length. The data are given in Table 41 

 and in Figure 20. The specific lengths regenerated are 0.17, 0.06, 0.11, 

 0.05, 0.03 and 0.03. They are shown in Table 41 and in Figure 21. As in 

 tlie case of the second regeneration the shortest removals have the 

 largest proportional amounts. This first period being the period of cell 



1.5 



13.0 



1^ 

 Figure 20 



;.6 4.6 8.2 



— >- Lengths removed in mm. 

 Rana claiiiilans First regenerations Four days 



16.7 



migration with very little cell division it is probable that the length of 

 the material furnished in this way, as measured along the main axis of 

 the individual, is independent of the level of the cut. The area of the cut 

 surface of course is greater at the more proximal than at the more distal 

 levels so that the actual total mass of regenerated material is greater at 

 the deeper levels. 



At six days the rate of first regenerations is rapidly increasing, 

 the maximiim rate coming between six and eight days. The lengths 

 regenerated at six days are respectively 0.47, 0.5, 1.0, 1.1, 1.6 and 1.6 mm. 



mm. 

 0.20 

 0.10 



1.5 



13.0 



Figure 21 



2.6 4.6 8.2 



— >- Lengths removed in mm. 

 RaiM damitans First regenerations Specific lengths 



16.7 



Four days 



