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ILLINOIS BIOLOGICAL MONOGRAPHS 



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other of both hind-legs plus the remaining fore-leg. The data are given 

 in Table 101. In two of the three cases the smaller additional degree of 

 injury shows the greater regeneration of the fore-leg. The average is 

 3.07 mm. for the lesser degree and 2.98 for the greater degree, an 

 advantage in favor of the lesser degree. 



It should be noted that this is not strictly comparable with the 

 main issue of Experiments I, II and III. Aside from the small number 

 of cases it is a comparison between two degrees of injury each of which 

 is of considerable extent. It may be that the removal of three of the 

 four legs is near the degree of injury yielding the maximum rate for each 

 removed leg. 



Experiment V Amblystoma punctatum Series 4010-4025 



A comparison is made between the regeneration of a half of the tail 

 when it alone is removed and when both fore-legs are removed at the 

 same time. Four individual comparisons are made at fourteen days. 

 The data are given in Table 102. The regenerated lengths and specific 

 lengths regenerated are ahead in two of the four cases for each of the 

 degrees of injury. The average regenerated length with no additional 

 injury is 5.1 mm. and with additional injury 5.0 mm. The specific 

 regenerated length is 0.65 with no additional injury and 0.68 with addi- 



TABLE 102 



Amblystoma punctatum Scries 4010-4025 



Regeneration of tail for different degrees of injury 



Fourteen days 



