THE NERVOUS SYSTEM AND CONSCIOUSNESS. 73 



on the left hemisphere. He bandaged the left eye, and allowed the 

 animal to recover from the chloroform. " Upon recovery it began to 

 grope about a little in loco, perfectly alert, but would not move from 

 its position ; hearing and the other senses were not affected, for there 

 was always a prompt reply to stimulation of these senses." The ani- 

 mal remained in this position for an hour. The bandage was then 

 removed from the left eye. "It instantly looked around, ran quickly 

 to the cage and joined its companions. When brought to the light, 

 as before, it flinched and turned away its head." Ferrier describes the 

 change in the animal's manner, after removal of the bandage, as most 

 complete and remarkable. On the following day the left eye was 

 again bandaged, but "the animal gave plain signs of vision, it ran 

 swiftly and accurately to the bars of the cage, thrust its head between 

 them, and began to drink from a cup of water." In his next experi- 

 ment Ferrier destroyed the angular gyrus on both hemispheres. He 

 found great difficulty in forming a right test for vision, one which 

 should discriminate between sight as a state of consciousness and sim- 

 ple reflex reaction to visual stimulation. 



The animal sat perfectly still and would not move from its posi- 

 tion. "The pupils contracted to light, and light flashed in the eyes 

 caused the animal to wince." It was utterly unwilling to move from 

 its place ; nothing else showed lack of vision. Ferrier's test was a 

 cup of tea, which the animal liked very much. Ferrier placed the tea 

 to the monkey's lips ; it began at once to drink eagerly. The cup was 

 then removed, but barely removed, from contact with the lips. " The 

 monkey seemed intensely anxious to drink, but could not find the tea, 

 though both eyes were looking straight at it." As soon as contact was 

 established, the monkey buried his head in the cup and followed it 

 around the room, as the cup was slowly lowered. 



Munk's experiments on vision led him to different results. He re- 

 moved the entire angular gyrus from the left hemisphere ; he then 

 raised the lids of the left eye with his fingers and touched parts of the 

 eye softly ; immediately there were blinking and vigorous movement 

 of the head and muscles of the eye. The animal made every effort 

 to draw back its head, and almost always accompanied these efforts 

 by striking with the left front-limb. With the right eye, however, 

 the case was entirely different. This eye could be pressed and pinched 

 constantly, and the animal remained perfectly quiet. 



If the finger or hand was brought suddenly up close to the left 

 eye there was blinking ; if to the right eye, no blinking at all resulted, 

 unless the lids were actually touched. Munk removed the center, 

 marked O, Fig. 1, from the occipital lobe in both hemispheres. He 

 says : " In from three to five days after the opex*ation there was nothing 

 abnormal in the hearing, smell, taste, movements, or sensations of the 

 animal, only in the territory of sight was there any peculiar disturb- 

 ance. The animal moved about the room or garden with perfect free- 



