478 
DR. D. FERRJER ON THE BRAIN OF MONKEYS. 
the cerebellar surface beneath was yellowish in colour, but not softened. No other 
lesion existed in the brain. 
This experiment was unsuccessful in so far as the object of localizing the lesion in the 
occipital lobes was concerned, but is a valuable confirmation of the results obtained by 
former experiments on the angular gyri. In this experiment, besides the complete 
removal of the left occipital lobe and extensive injury to the right, the angular gyrus 
was deeply involved on both sides, not throughout, however. The lesion was, however, 
extensive enough to produce total blindness ; and it further illustrates the fact that when 
the angular gyrus is destroyed on both sides no compensation of visual perception 
occurs. 
Beyond the fact of loss of sight, which is to be attributed to the lesion of the angular 
gyri, the lesions of the occipital lobes were in a great measure negative, the animal 
retaining its muscular powers, and apparently other senses, and still exhibiting, though 
to a less extent than before, its desire for food. 
Experiment XXII. 
January 22nd, 1875. — The occipital lobes were exposed on both sides in a monkey, 
and the surface exposed destroyed by the cautery, which was also passed deeply into 
the interior of the lobes, in order to cause as much disorganization as possible. Care was 
taken not to injure the angular gyri. 
The operation was completed at 3.30 p.m. 
4.10 p.m. The animal after lying in a state of stupor till now begins to move, but 
staggers a good deal. The eyes are open and the pupils dilated. 
It indicates consciousness by turning its head when called to. 
4.45 p.m. Sits quietly with its head down on its chest. It drank a little tea in which 
its mouth was kept immersed. Turned fiercely round on its tail being pinched. 
5.45 p.m. Gives emphatic evidence of sight. Ban away when I approached it, carefully 
avoiding obstacles. Seeing its cage door open, it entered and mounted on its perch, 
carefully avoiding the cat which had taken up its quarters there. 
Tried to escape my hand when I offered to lay hold of it, but picked up a raisin which 
I had left on the perch. 
8 p.m. When not disturbed sits quietly with its head bent on its chest. Easily roused. 
Does not take any food or drink offered to it. 
12 midnight. Is sound asleep on its perch. Has not eaten any of the food left in 
the cage. 
January 23 rd . — 10 a.m. Animal found sitting in the cage with the head bent as 
before. Drank a little milk held up to its lips. When removed from the cage walked 
about somewhat unsteadily, and then sat down as before. The eyes are partially closed 
from oedema of the eyelids. Sight continues. Made for a warm corner by the fire. 
Wakes up and grunts when called to. There is no loss of motion or sensation as far as 
can be seen. 
