3i6 



Journal of Comparative Neurology. 



The average increase in number for the two sides 

 shows for the distance S^ to S, (see Figure 2) an increase oi 

 85 fibers, for the distance from S, to T+P of 14 fibers, and 

 from T+P to T and P of 100 fibers. While this increase in the 

 number of fibers is not proportional to the distances between 

 the various levels, nevertheless the shortest distance, S, to 

 T-f-P, gives the least increase. 



4. Proportion of- the number ot muscular to the number of 



cutaneous fibers. 



The proportion of the number of muscular to the number 

 of cutaneous fibers will be of more definite interest when further 

 data concerning the weight of the muscles and the area of the 

 skin innervated have been obtained. As, however, the cutane- 

 ous and the muscular fibers were distinguished in this series of 

 enumerations the results are recorded. 



Tables XIII and XIV give in detail the number of mus- 

 cular and of cutaneous fibers for the thigh and for the shank. 

 Table XIII gives as the totals for the thigh 1805 muscular, 

 1676 cutaneous fibers for the left side, 1830 muscular, 1678 

 cutaneous fibers for the right side. In this instance the mus- 

 cular fibers, while surpassing in number the cutaneous fibers, 

 are not so much in excess as in the two frogs which furnished 

 the data for the preceding study (Dunn, 1900, pp. 233, 234). 

 The proportional differences in the several frogs seem to be 

 matters of individual variation. 



TABLE Xin. 



Showing the number of muscular and of cutaneous fibers inner- 

 vating the thigh. 



