268 Ross Granville Harrison 



Each bud developed into but a single appendage, and neither 

 of these were so far advanced in development as the limbs in the 

 other cases described. Twenty-six days after the transplantation 

 the specimen was preserved and afterward examined in sections. 

 Both of the transplanted legs are innervated principally by the r. 

 lateralis vagi. In the case of the normal transplanted limb on 

 the left side a branch is given off from this nerve, which after 

 skirting along a large vesicle, formed from the transplanted tissue, 

 finally enters the thigh. Here it maybe followed for some distance 

 as the n. ischiadicus. In addition to this nerve a small branch 

 from one of the spinal nerves extends out along the lateral surface 

 of the thigh in the region normally supplied by the r. cutaneus 

 femoris lateralis. 



In the nerveless transplanted limb, which is cut more favorably 

 than the other, the n. ischiadicus formed by the lateralis vagi may 

 be readily traced to the knee. In this region it divides, one branch 

 running to the skin where it may be followed some distance fur- 

 ther. The other ultimately becomes lost in the mesenchyme. 

 No traces of lateral line sense organs in the leg could be found. 

 There are irregularities in the development of the cartilages in 

 this limb and the muscles are scarcely differentiated at all so that 

 the topographical relations are to some extent uncertain. 



In comparing the above experiments it is seen that with a single 

 exception all of the transplanted limbs contain nerves. There 

 are great individual differences as regards completeness of inner- 

 vation but in this respect the corresponding limbs in the different 

 experiments do not occupy the same relative position. These 

 features are expressed in the accompanying table. From this 

 it is clear that the limbs which have been taken from nerveless 

 individuals have fared rather better as regards innervation than 

 the normal transplanted limbs have, and also that while the acces- 

 sory limbs are less completely innervated in three cases, they are 

 more completely innervated in two. 



The most constant nerve is the ischiadicus, and as might be 

 expected the proximal regions of the transplanted limbs are the 

 most completely supplied. In general the cutaneous nerves are 



