Experiments in Transplanting Lunhs 



257 



arches backward again running into the primary Hmb as its r. 

 cutaneus femoris hiterahs, a nerve normally derived from the 

 cruralis, which in turn is usually composed of fibers from the 

 eighth and sometimes also the ninth spinal nerves. 



The seventh and eighth nerves are large trunks which anasto- 

 mose freely with one another and it is from this plexus that both 

 the primary and secondary limbs are principally innervated. The 

 arrangement of the plexus is shown in Fig. 7, which was drawn 

 from a graphic reconstruction. 



The first nerve to be given off from the plexus is the cruralis, 



Fig. 7 Plexus from which the "aneurogenic'' limbs are innervated, drawn from a graphic recon- 

 struction projected to a horizontal plane. F7/, r. abdominalis n. spinalis VII; VIII, r. abdommalis n. 

 spinalis VIII; a, n. cruralis of primary limb; h, r. profundus posterior; c, n. ischiadicus of the primary- 

 limb; d, r. cutaneus femoris posterior of the primary limb; e and /, rr. accessorii cutanei femoris pos- 

 teriores of the accessory limb; g, n. ischiadicus of the accessory limb; /;, n. ilio-hypogastricus of the host; /, 

 branch to the plexus lumbo-sacralis of the host. X 67. 



which originates from eighth nerve in a stout branch that runs 

 more directly laterally than the main stem. At the point where it 

 crosses the seventh it forms an anastomosis, giving off fibers to the 

 latter, and perhaps, though not certainly receiving fibers from the 

 same. It then runs a short distance anteriorly, arching around the 

 ilium on the surface of the m. iliacus internus (Fig. 8). It gives 

 off a branch to this muscle and then runs distally to the thigh for 



