FUNCTIONS OF THE BRAIN-STEM AS A WHOLE 627 



ered much from cold at times. He likewise never tried to hold a bone with his 

 fore paws. 



In view of this it is the more remarkable that the animal again acquired the 

 ability to eat and to drink. For a long time it was necessary to push the food 

 far back in the animal's throat, for when it was merely laid on the front end of 

 his tongue it was neither chewed nor swallowed. On the twenty-third day after 

 the last operation it became unnecessary to push the food so deep into the mouth. 

 It was seized by the tongue and carried back when placed pretty well forward 

 in the mouth. Gradually the dog got better control of his jaws, and finally had 

 made such progress that he could drink a large bowl of milk when his snout 

 was held close in it, and could eat meat when the dish was placed so that his snout 

 touched the food. The reason for touching the food will be apparent when we 

 remember that the sense of smell was entirely lost and the sense of sight reduced 

 to almost nothing. 



The following experiment shows that the animal could do a rather more 

 difficult task. A small blind alley was made by means of two boards placed 

 endwise against the wall. When the dog was let into this alley, which was so 

 narrow that he could not turn round in it, he walked to the end and reached 

 up on the wall, " trying " in vain to get out. Finally he began to walk back- 

 ward, and after about twenty minutes managed to back all the way out, although 

 the length of the alley was only about twice the length of the animal. 



It follows from these observations that a dog without his cerebrum is 

 able to carry out all of the functions necessary to life, if only his food be 

 placed immediately in front of his nose; that he is still able to perform 

 locomotor movements satisfactorily; that these movements are influenced and 

 regulated by the muscular and tactile senses; also that the sense of hearing 

 and the sense of sight, although in a very slight degree, can influence his 

 movements. Finally, his behavior during hunger and after taking food teach 

 us that the bodily desires are still " felt." The cerebrum we must conclude 

 is not necessary for any of these functions, nor for passing from the sleeping 

 to the waking condition and vice versa. 



Flechsig was able to determine on a human monster, in which only the 

 lower parts of the brain up to and including the posterior corpora quadrigemina 

 were developed, that these findings for the dog apply at least in part to man. 

 The child lived for a day and a half and during this time gave various signs of 

 discontent. It whimpered occasionally and its whimperings became more vig- 

 orous and various movements of its limbs became more active when its skin was 

 pinched. 



The observations here brought together on the effects of removing the 

 cerebrum from different vertebrates may be summarized briefly as follows: 

 these effects are very slight or even unnoticeable in the lowest vertebrates, 

 but the higher we ascend the scale of animal life, the more pronounced and 

 extensive they become. But even in the highest of the lower animals studied 

 (dog), the functions of the central nervous system which remain are sufficient 

 to maintain all the vital processes necessary for life, with the single exception 

 of seeking food. The effects are chiefly upon the highest powers of the 

 nervous system, especially upon those which we comprehend as belonging to 

 consciousness. For these powers the cerebrum in the highest vertebrates at 



