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the maximum for the frog tadpole which comes between four and six 

 days for second regenerations and between six and eight days for 

 first regenerations. The period of decline in rate is also more extended 

 in these salamander larvae than in the frog tadpoles of Experiments 

 I and II. 



On account of the irregularity of the data it is not possible to 

 study the acceleration of rate for the present data. 



The percentage increments per day are given in Table 68. The 

 values for the seven time periods are respectively 8, 71, 20, 23, 14, 4 

 and 7. The greatest percentage increment comes between 4 and 6 

 days as in the case of the frog tadpoles. An earlier period, that be- 

 tween two and four days is represented here. During this period 

 the percentage increment is low. If this value can be accepted the 

 curve here includes the very steep ascending portion discussed above. 

 The irregularities in rate to which the salamander larvae are subject 

 and the fact that the low value during this period does not appear in 

 all the salamander experiments however makes the interpretation 

 doubtful. 



TABLE 66 

 Amblystoma punctatum Series 4600-5052 



Rate of regeneration of tail per day at different times during the regenerative 

 process for five different levels 



