ON THE INTERCHANGE OF THE LIMBS OF THE 

 CHICK BY TRANSPLANTATION. 



FLORENCE PEEBLES, PH.D. 



The experiments of Lillie ('04) and of Shorey ('09) have demon- 

 strated that the injury of certain parts, and the removal of organs 

 in the early stages of the embryonic development of the chick 

 are rarely followed by regeneration of the lost part. Lillie found 

 some evidence of the regeneration of the notochord, but a new 

 wing did not develop after removal of the bud. From these 

 experiments he drew the conclusion that the embryo of the chick 

 possesses little more power of regeneration than the adult. 

 Shorey also removed the wing buds of embryos of three to six 

 days' incubation, and although the region healed and develop- 

 ment of other parts proceeded normally, the wing buds did not 

 show any sign of regenerative activity. 



In the winter of 1908 I undertook a series of experiments, first 

 to find out if the limb buds after removal could be grafted on 

 again, and if so whether a leg bud grafted on the proximal part 

 of the wing would develop into a wing or a leg, and vice versa, 

 if a wing bud when grafted on the proximal part of the leg would 

 develop into a leg or a wing. 



Experiments of this kind on the chick are necessarily attended 

 with many difficulties, so that even under the most favorable 

 conditions, the percentage of successful operations is exceedingly 

 small. My results, therefore, are largely negative, but it may 

 be of interest to note what has been accomplished in the hope 

 that more perfect methods will enable some one to obtain more 

 satisfactory results. 



Two general methods were followed. In the first series of 

 experiments the eggs were left in the shell. A window was made 

 above the embryo and after the operation it was sealed by the 

 method which I ('98) used in experiments on the primitive streak. 

 This method has since been used by other investigators with 

 success. In the later experiments the eggs were removed from 



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