The KxcitHbK- Cortex id" tlie Chiiiipanzcc, ( )ianij-rtaii. and (Joiilla 141 



insU'tttl tlcxioii of liip lollowed by dorsal llexioii of aiikK* and llexion of 

 knee, followed further by tlexion of all toes except hallux, uioveiiimt '.W)'.\. 



A^ain. in the sauie aninuil and same hemisphere, point liOti ^ave retju- 

 larly, wiien stimulated after points relatively inditierent to it. tlie lesponse : 

 flexion of little and 4th toes rapidly followetl by flexion of 3rd and 2nd, 

 and then followed by plantar llexion o\' anojle. an«l latei- adduction of 

 hallux. W'iieii .stimulated next and ijuickly after point 306. but with 

 allowance of time for the movenient from 30(5 to subside completely, 

 point 319 evoked no louo;er movement 319, but the following; tlexion of 

 toes without hallux, followed by plantar flexion ot ankle, followed by 

 adduction of hallux, movement 29<S. 



Again, point 268 gave as its regular lespouse flexion ol hallux, followed 

 by flexion of toes, followed by plantar flexion of ankle. Point 319, when 

 .stimulated next and .soon after 268, evoked as response, simultaneous 

 flexion of toes and hallux, followed by plantar flexion of ankle. 



Again, point 331, which evoked flexion of knee when stimulated in 

 quick succession to point 342. evoked when stimulated in <{uick succession 

 to point 263 extension of hallux, the regular response from point 2(13 itself 

 beine; extension of hallux, followed by extension of the remainin<r toes, 

 followed further by dor.sal llexion of ankle, and Anally by flexion of hip. 



Again, point 232 in the same experiment, in arm area, yielding 

 ordinarily flexion of elbow^ yielded when stimulated (juickly next after 

 point 127, which was yielding flexion of thumb, flexion of thumb followed 

 by flexion of elbow, 140. 



Again, in another animal, the following " deviation " occurred. The 

 examination of the motor area had in this experiment been begun at the 

 top limit of the arm area in shoulder region, and proceeded S3'stematically 

 from point to point in the downward direction. Followed in this manner, 

 elbow flexion soon became the leading (primary) movement, and continued 

 so ver3' nearly or even quite down to the inferior genu of sulc. centralis. 

 Beyond a certain point, which was minutely and precisely marked on the 

 map made, elbow flexion disappeared abruptly, and facial movements 

 appeared in the form of closure of opposite eyelids. The lowei- margin of 

 arm area having thus evidently been reached, we turned to the delimitation 

 of the face area. The examination of this area we started at the lower 

 (Sylvian) end of sulc. centralis, and thence proceeded point by point up- 

 ward along the precentral gyrus not far in front of sulc. centralis. In due 

 course the point yielding closure of opposite eye was again reached, and it 

 was found that then on proceeding farther upward to the point that had 

 previously yielded elbow flexion as its primary movement, that point now 

 yielded adduction of thumb as its primary movement, and a little farther 

 upward movement of index, chiefly extension, was added to that of thumb : 

 and movements of thumb and index continued to be the primary move- 

 ments right up through the region which previously had given elbow 

 flexion as primary response, and thumb and index movements as primary 



