OF TFIE GYRUS MARGINALIS AND GYRUS FORNICATUS IN MONKEYS. 347 
Post mortem, it w.iis found that the middle part of the gyrus foniicatus was 
destroyed, and that the corresponding part of tlie marginal convolution was somewhat 
injured and depressed (fig. 5a), Besides the lesion of the temporal lobes above 
mentioned, the surface of the brain just above and in front of the Sylvian fissure was 
also found to be slightly injured. 
Degenerations Observed. 
In the midbrain, pons, and medulla the slu'inking of the pyramidal bundles on the 
right side, as compared with those of the left, is very distinctly visible to the naked 
eye. They are also more deeply stained with aniline blue-black on the right than on 
the left side. 
Microscopically, a number of degenerated fibres can be seen on the right side. In 
the medulla there is also some sclerosis. 
Spinal Cord. —Level of second cervical nerve. Degeneration could be seen, even with 
the naked eye, in the lateral pyramidal tract on the left side (fig. 56). There is a 
little degeneration in the pyramidal tract on the same side as the lesion (right), 
although less than after an extensive marginal or other motor lesion. 
Level of sixth cervical nerve.—The degeneration has much the same appearance 
here as at the second cervical, except that it is rather better defined. 
Level of fifth dorsal nerve.—The patch of degeoeration is smaller than in the cervical 
region, but denser; it lies somewhat closer to the surface, especially nearer the 
posterior root exit (fig. 5c). 
At the level of the eighth dorsal the patch is perceptibly smaller than at the fifth. 
Lumbar Region. —At the level of the first nerve the degeneration is less extensive. 
It lies along the circumference of the cord near the apex of the posterior cornu. 
At the level of the fifth lumbar the dee’eneration can still be made out without 
o 
difficulty. 
That the degeneration in this case had nothing to do with the lesions in the tem¬ 
poral lobes has been ascertained by carefully investigating other cords in which there 
were lesions in those lobes only. 
Methods Employed in Preparing the Tissues for Microscopic Exainination. 
The brain and spinal cord of each animal, immediately after removal from the body, 
were placed in Muller’s fluid, or bichromate of potash (2 per cent, solution), and 
hardened in this for not less than a month, the fluid being repeatedly changed. After 
hardening, they were first rinsed with water, or placed directly into methylated spirit 
without washing, and allowed to remain in this until cut up. 
For staining by Weigert’s or Pal’s method, I have obtained better results if the 
brain has not been allowed to remain in spirit for more than a week, although the 
2 Y 2 
