Experiments iti Transplanting Limbs 255 



yolk being nearly complete, the transplantation of the limbs was 

 undertaken. During the intervening period the normal speci- 

 mens had developed a little more rapidly than the nerveless one, 

 the external form of which is shown in Fig. 3. The limb buds 

 were transplanted to the side of the body of one of the normal 

 individuals, dorsal and anterior to its natural hind limbs, the right 

 limb from the nerveless individual being placed on the right and the 

 left limb of the normal one on the left. 



After removal of the hind limb for the purpose of transplanta- 

 tion the nerveless larva was preserved and afterward cut into 

 sections. It was found that the operation for the removal of the 

 spinal cord had been entirely successful. The central nervous 

 system ends abruptly immediately behind the auditory vesicle and 

 no ganglion cells are to be found posterior to the vagus. The 

 brain has undergone marked histolytic changes, practically no 



© 



Fig. 3 Embryo from which the nerveless limb in Experiment I was taken. X9. 



normal nerve cells being left in it. No longitudinal bundle fibers 

 have grown out posteriorly from the brain and there are no signs 

 of regeneration. The only nerves to be found in the body are those 

 arising in the head. It is therefore certain that the limb trans- 

 planted from this individual was entirely nerveless. 



The tadpole was kept alive until May 22, during which time it 

 grew rapidly and both of the transplanted limbs as well as the nor- 

 mal ones developed well. Each one of the transplanted buds 

 gave rise to a pair of legs, as Braus described in some of his cases. 

 The photograph (Fig. 4), which was taken after the specimen was 

 preserved, shows the "aneurogenic" or "nerveless" extremities 

 in addition to the natural ones. The thigh which projects dor- 

 sally is part of the primary limb, a right hind leg, while the other 

 leg, a left, which projects directly caudalward, is the accessory one. ^^ 



-^Tornier and Braus have shown that the accessory limb is the mirror image of the primal^ one from 

 which it is budded. 



