Dunn, Medidlated Nerve Fibers. 719 



8. The absolute enunierations for the ventral root nerve fibers are 

 vitiated by the dropping out from the unoperated leg of a small 

 number of medullated efferent nerve fibers. This loss increases 

 toward the periphery. 



9. Correcting the enumerations by those of frog IIB, we find that 

 the medullated afferent fibers make up less than half of the total 

 nerve fiber supply to the muscles. This holds true for the thigh and 

 for the shank. 



10. The efferent medullated nerve fibers are not distributed to the 

 two segments of the leg according to the respective weights of mus- 

 cles, but the distal segment has a greater richness of innervation. 



11. JSTo detailed statement of the innervation of the foot can be 

 made at this time, but of the total number of afferent medullated 

 nerve fibers to the leg, 34 per cent innervate the foot, as against 45 

 per cent to the thigh and 21 per cent to the shank. 



12. Among the afferent medullated nerve fibers less variation in 

 size occurs among those passing to muscles than among those passing 

 to the skin. 



13. The largest afferent nerve fibers in both the thigh and the 

 shank pass to the muscles and not to the skin. 



14. The previous finding, Dunn, 1902, that the largest medul- 

 lated nerve fibers passing to the leg run the shortest distance, and in 

 each segment are given off in the branches to that segment, is con- 

 firmed here, and is established in regard to the dorsal ropt medullated 

 nerve fibers. 



15. The individual afferent nerve fibers in the operated leg show 

 some deviation from the one to one relation of the axis cylinder and 

 medullary sheath found by Donaldson and Hoke, 1905, due to a slight 

 swelling of the ax's cylinder and an associated thinning of the medul- 

 lated sheath. 



