i68 



ESTHER F. BYRNES. 



After regeneration the double nature of the radio-ulnare is in- 

 variably strongly marked by a deep groove showing the line of 

 demarkation between the ulnar and the radial regions. There is 

 no trace of where the amputation occurred, the regenerated end 

 being perfectly normal in proportion, and showing complete 

 continuity with the upper part of the bone. 



While the frog larvae were regenerating the imperfect limbs 

 whose skeletal structures are shown in the text figures, similar 

 experiments were made on some Amblystoma larva; about three 



FIG. 3. The skeleton of a regener- 

 ated hand. 



FIG. 4. The skeleton of a partly 

 regenerated anterior hand. P, the 

 pollyx ; C, the carpus. 



months old. As soon as an Amblystouia had regenerated the lost 

 limb, the regenerated limb was again amputated, so that toward 

 the close of the experiments, the Aniblystouice were in possession 

 of perfectly formed limbs, after having regenerated five in rapid 

 succession. Each of the five limbs was not only normal in form 

 and in the number of its parts, but it was also normal in size, the 

 larvae apparently having suffered no loss of power, even tempo- 

 rarily, to completely recover from the injury. 



