480 
DE. D. TERRIER ON THE BEAIN OP MONKEYS. 
In this experiment the results as regards sensation and voluntary motion were entirely 
negative. Sight became affected later ; and this can be accounted for by the proximity 
of the angular gyrus to the lesion, and the commencement of pathological change in its 
substance. Nothing further was to be observed, except the dull dejection and melan- 
choly attitude of the animal and its persistent refusal of food. 
Experiment XXIII. 
March 10 th, 1875. — The occipital lobes were exposed in a small and rather weakly 
monkey, and the lobes severed by perpendicular section with hot wires about a quarter 
of an inch posterior to the parieto-occipital fissure, so as to avoid all interference with 
the angular gyrus. The operation was completed at 4.30 p.m., the animal having by 
the time the wound was dressed almost completely regained consciousness. 
4.45 p.m. Begins to move about in rather a staggering manner, but exhibiting no 
muscular paralysis. 
4.55 p.m. Can see quite well, as it avoids obstacles, and when removed regains its 
place by the fire. Twitches its ear and turns its head when called to, or a noise made. 
Can sit quite steadily. 
7 p.m. Sits still looking about vacantly. Will only move when nudged. Tactile 
sensation is unimpaired. Sight and hearing continue. Withdrew its head sharply 
when acetic acid was held before its nose. Made movements of tongue and mouth, as if 
to expel it when colocynth was placed in its mouth. Circulation and respiration regular 
and normal. 
The animal has refused food and drink. 
7.45 p.m. Drank a few teaspoonfuls of tea held up to its lips, and accidentally placing 
its hand in the dish stooped and drank up the contents. 
When left to itself, takes up a position with its head bent on its chest and covered 
with its hands. 
8.45 p.m. Remains as before. Refuses to eat or drink. When a dish of milk was 
held before it in such a manner that it could not hold its head down without immersing 
its mouth in the liquid, it sipped a little but wished to avert its head. 
9.40 p.m. Reaction to taste again tried with aloes, and again discomfort manifested. 
Turned away its head when assafcetida was held before its nostrils. Active reaction to 
acetic acid. Smelt at its hand on which some assafcetida had been spilt. 
12 midnight. Lies asleep in cage breathing quietly. Easily roused by a touch on 
its hand, which caused it to open its eyes. Animal weak. 
March 11 th. — 9.30 a.m. Found dead in its cage and rigid, death having occurred in 
the night. 
Post mortem Examination . — The brain was everywhere normal except in the region 
of the occipital lobes. The occipital lobes had been completely divided and removed on 
both sides, but more on the right than on the left. The parts removed are indicated in 
figures 32, 33, 34 by the shading. 
