THE DOCTRINE OF HUMAN AUTOMATISM. 277 



into water, it will swim, just like the brainleso water-beetle already 

 mentioned 



But if, instead of removing the whole of the brain, we take 

 away (as in Goltz's experiments) only the cerebral hemispheres, 

 leaving the whole axial cord uninjured, the condition of the frog 

 is precisely assimilated to that of the pigeons from which the 

 cerebral hemispheres were removed by Flourens, Magendie, and 

 I.ongetjWith results remarkably similar. Goltz's frog, like Flourens's 

 pigeon, sits unmoved as if profoundly asleep, apparently seeing 

 nothing and hearing nothing ; but it will jump when irritated, and 

 shows that its movements are guided (whether consciously or not) 

 by the incidence of light on its eyes ; for if a book be placed at 

 some little distance in front, between the frog and the light, it will 

 avoid the book, when excited to jump, by passing to the right t 

 hand or the left. And so Flourens's pigeon, when excited to walk 

 by being pushed forwards, would avoid objects that lay in its 

 way ; and, according to the observation of Longet, if a lighted 

 candle was made to describe a circle before its eyes, the head 

 of the bird would move in a corresponding manner. Goltz's frog 

 and Flourens's pigeon, moreover, while taking no notice of food, 

 and making no effort to feed themselves, swallow food that is put 

 into their mouths, and may be thus kept alive and vigorous for 

 weeks or months, Goltz's frog croaking whenever a particular 

 part of its back is stroked. The pigeon, moreover, gets upon its 

 legs again when overthrown, and moves its wings in flight if 

 thrown into the air, thus showing that the mechanism of its 

 ordinary actions remains uninjured, though it does not spontane- 

 ously exert it. This is proved, in regard to the frog, by the 

 curious observations of Goltz, which Professor Huxley has himself 

 verified : — 



" If put on the hand the frog sits there, crouched, perfectly 

 ''quiet, and would remain so unless stimulated to action; but if 

 "the hand be inclined very gently and slowly, so that the frog 

 "would naturally slip off, the creature's fore-paws are shifted on to 

 " the edge of the hand, until he can just prevent himself from 

 " falling. If the turning of the hand be slowly continued, he 

 "mounts up with great care and deliberation, putting first one leg 

 " forward and then the other, until he balances himself with per- 



