182 Ley ton and Sherrington 



left hand. In the left hand index is often both extended and flexed inde- 

 pendently of the other fingers, but never in right. Thumb : this digit in 

 the normal (left) hand is used less than might have been supposed ; as 

 mentioned above, the thumb seems too short to be very competent for 

 oj^position to the other digits, at least for many purposes. In the paretic 

 right hand the thumb slightly but indubitably combines with the other 

 digits in a general grasp with the hand, but this grasp movement is in 

 reality less abnormal to inspection than it proves to be when the grasp is 

 felt. The animal had been taught to shake hands, and with either hand. 

 When one shakes hands with its right hand, one feels that it exerts very 

 little compression or force with thumb of that hand ; whereas, when one 

 shakes hands with its left hand, the compressive force of the left thumb is 

 felt to be good and considerable. Yet the right thumb is employed by 

 it to a far from negligible degree. Thus it frequently employs the thumb 

 of right hand in holding a banana, an apple, etc., with that hand ; also iu 

 peeling a banana, the fruit itself being held in the left hand. Occasionally 

 when eating fruit it holds the fruit with both hands, the right contributino- 

 seemingly an equal share of manipulation with the left. Thus, on one 

 occasion, the right thumb was clearly seen to be employed with successful 

 force to break a banana open, the ends of the fruit being held each with 

 one hand, the thumb of each hand pressing down on the convexity of the 

 banana from above, and so breaking the fruit. Sometimes the animal 

 feeds from fruit held to the mouth by right hand alone. The ulnar three 

 fingers of right hand are well used, not only for grasping, but apparently 

 for all their full variety of movements. 



May 3. — Condition of right arm appears the same as when last note 

 was written. Animal lively and well. The scalp wound has been com- 

 pletely healed for more than a fortnight. 



Animal anassthetised, and the left hemisphere re-exposed in the same 

 situation as before. Faradisation of the old lesion yields nothing. Stimula- 

 tion of cortex adjoining it in front and behind yields nothing. Faradisa- 

 tion of post-centralis for the whole exposed extent of it yields nothing. 

 Faradisation of precentralis adjoining the lesion above evokes brisk and 

 strong retraction of shoulder, but no movement of wrist or hand, and ques- 

 tionably any of elbow. Faradisation of precentralis adjoining lesion below 

 evokes retraction of opposite angle of mouth, especially of upper lip. 



The old lesion was re-excised and slightly extended in depth, and the 

 cortex adjoining its upper edge was excised for a 3-mm. strip. The wound 

 was then closed aseptically. 



May 4. — Animal very well and active ; feeds eagerly, dances about and 

 stamps on floor to attract notice ; climbs about, coos, and calls, etc. Face 

 perfectly normal. Right arm, including hand, is used as freely and well 

 as before the last operation, but there seems somewhat less free use of the 

 shoulder. The limb is, however, used for climbing, swinging, holding food, 

 etc., apparently just as before. 



