AUTHOR 8 ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE, JANUARY 16 



EXPERIMENTS ON THE TRANSPLANTATION OF 

 LIMBS IN AMBLYSTOMA 



FURTHER OBSERVATIONS ON PERIPHERAL NERVE CONNECTIONS 



S. R. DETWILER 



The Anatomical Laboratories, Yale School of Medicine, New Haven, Connecticut, 

 and the Peking Union Medical College, Peking 



THIRTY-TWO FIGURES 



INTRODUCTION 



In a recent paper dealing with the function and peripheral 

 innervation of transplanted limbs (Detwiler, '20), reference was 

 made to the striking tendency on the part of the normal limb 

 nerves to supply the appendage when the latter was transplanted 

 a considerable distance away from its typical site. In these 

 experiments it was found that shifting the anterior limb a given 

 number of body segments caudal to its normal position on the 

 same embryo did not effect a corresponding shifting of the seg- 

 mental nerves contributing to its plexus. Limbs transplanted 

 caudally the distance of four and five body segments received one 

 or more nerves from the original limb level of the cord (Detwiler, 

 op. cit., table 2, p. 133). 



The facts were also brought out that transplanted limbs which 

 received innervation from the normal limb level of the cord 

 functioned more perfectly than did those whose segmental nerves 

 were derived from the post-limb level, and that the limbs showed 

 a gradually increasing loss of function as they were trans- 

 planted farther and farther away from the normal situation. 

 This was attributed to diminution of connections within the 

 central nervous system rather than to a corresponding decrease 

 in effective peripheral innervation or to structural deficiencies 

 within the limb and the shoulder-girdle. The cumulative evi- 

 dence suggested that the more perfect function of limbs whose 



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