ON THE MAMMALIAN NERVOUS SYSTEM. 



457 



MONKEY. 



It will be seen that with " minimal " excitation the average effect obtained in the 

 sciatic nerve of the Monkey by the excitation of the posterior column of the same 

 side was nearly eight times as great as that of the posterior column of the opposite 

 side. A small effect was obtained once after excitation of the lateral column of the 

 same side, otherwise these results are in complete harmony with those in the Cat, 



With the stronger stimulus the average effects following excitation of the two 

 posterior columns have the relation of nearly five to one, the larger being due to 

 that of the posterior of the same side ; and, as in the Cat, a marked effect follows the 

 excitation of the lateral of the same side, this being equal to that evoked by stimula- 

 tion of the posterior column of the opposite side. 



Finally, if all the results in both animals are blended and we compare both the 

 average effect and the highest deflection obtained in response to excitation of each of 

 the columns, the comparison shows the following results. 



MDCCCXCI. B. 



3 N 



