36 
PROFESSORS V. HORSLEY AND E. A. SCHlFER 
27. 
Lesion 1. — Removal of the whole of the external and posterior surface of the left 
occipital lobe. The upper part of the angular gyrus was also to some extent involved 
in the lesion. 
Result. — Right hemiopia apparently complete ; objects on the right of the mesial 
plane are not seen. This condition lasted some weeks, but gradually improved, so 
that after five months the most careful testing failed to elicit any imperfection of 
visual perception. 
Lesion 2. — Six months after the first operation the cortex of the quadrate lobule of 
the same side (the left) was removed. The result of this second opemtion, so far as 
could be determined, was entirely negative. 
The brain is represented in figs. 27a and B, Plate 4. 
28. 
Lesion 1. — The greater part of the left tempore -sphenoidal lobe was cut away, tlie 
descending cornu of the ventricle opened, and the hippocampus major removed. The 
lesion included all but a small part of the hippocampal gyrus. 
Result. — We could detect no difference of sensibility on the two sides, nor was there 
any other noticeable symptom either on the day after the operation or on any 
subsequent occasion. 
Lesion 2. — A nearly equal extent of the right temporo-sphenoidal lobe was removed 
three weeks later, but on this side the gyrus hippocampi remained almost untouched. 
The ventricle was again opened and the hippocampus major cut away. 
Result. — The result was again negative ; again we could detect no deficiency in 
sensibility on the opposite side. 
This animal contracted pneumonia and died on the fifth day after the second 
operation. The occurrence of this illness prevented any accurate testing of the other 
special senses. 
The brain is represented in 6 figures on Plate 4, both right and left hemispheres 
being shown as seen (1) from without, (2) from below, and (3) in section. 
29. 
Lesion. — A large part of the left temporo-sphenoidal lobe was removed, the ventricle 
(descending cornu) opened, and a considerable piece of the hippocampus major excised. 
The superior temporo-sphenoidal gyrus, the anterior extremity of the lobe, and the 
hippocampal gyrus were only in part involved in the lesion. 
Result. — We could detect no difference of sensibihty upon the two sides. There 
was no muscular paralysis, nor any other obvious loss of function. We did not test 
this animal's hearing, intending to reserve the tests for this until the operation should 
be repeated upon the other side. This second operation was performed three weeks 
after the first (the wound caused by the firiit operation having completely healed, 
