4:00 NERVOUS SYSTEM. 



of enfeeblement of the muscular system, but voluntary mo- 

 tion and general sensibility are retained. There can be no 

 doubt upon these points. As far as voluntary motion is 

 concerned, an animal operated upon in this way is in nearly 

 the same condition as one simply deprived of the cerebral 

 hemispheres. There are no voluntary movements which 

 show any degree of intelligence, but the animal can stand, 

 and various consecutive movements are executed, which are 

 entirely different from the simple reflex acts depending 

 exclusively upon the spinal cord. The coordination of move- 

 ments is perfect, unless the cerebellum be removed. As re- 

 gards general sensibility, an animal deprived of all the en- 

 cephalic ganglia except the tuber annulare and the medulla 

 oblongata undoubtedly feels pain. This has been demon- 

 strated in the most conclusive manner by Longet, 1 and has 

 been shown even more satisfactorily by Yulpian. 8 In rabbits, 

 rats, etc., after removal of the cerebrum, corpora striata, and 

 optic thalami, pinching of the ear or foot is immediately 

 followed by prolonged and plaintive cries. Both of the 

 experimenters referred to insist upon the character of these 

 cries as indicating the actual perception of painful impres- 

 sions, and as very different from cries that are purely reflex, 

 according to the ordinary acceptation of this term. Longet 

 alludes to the voluntary movements and the cries observed 

 in persons subjected to painful surgical operations, when 

 incompletely under the influence of an anaesthetic, concern- 

 ing the character of which there can be no doubt. He re- 

 gards the movements as voluntary, and the cries as evidence 

 of the acute perception of pain ; but it is well known that 

 such patients have no recollection of any painful impression, 

 though they have apparently experienced great suffering. 

 As far as we can judge from what we positively know of the 

 function^ of the encephalic centres, the pain under these 

 circumstances is perceived by some nerve-centre, probably 



1 LONGET, Trai/e de physiologic, Paris, 1869, tome iii., p. 396. 



2 VULPIAN, Systeme nerveux, Paris, 1866, p. 542, et seq. 



