85] 



RATE OF REGENERATION— ZELENY 



85 



completed regenerations are less than the removed lengths. The specific 

 completed regenerated lengths obtained as before by dividing by the 

 removed lengths are 0.61, 0.46, 0.39, 0.33, 0.42 and 0.41, as shown in 

 table 42 and figure 35. The greater specific lengths from the shortest 

 removals are probablj' due as in the case of the second regenerations 

 to the fact that a greater proportion of their substance is made up of 

 cells that have migrated over the cut surface during the first stages of 

 regeneration. This migrated material is not essentially different in axial 

 length at the diiferent levels. The largest removals have a greater spe- 

 cific length than the medium ones because regeneration continues at the 

 former levels after it has ceased at the latter. 



On the whole there is no essential difference between the results 

 obtained from first regenerations and those obtained from second regen- 

 erations. The latter give the more regular data because the averages are 

 taken from a larger number of individuals. 



Rana clamitans 



TABLE 41 

 Series 3676-3765 



First regenerations 



