The specimens submitted for examination were:
(a) Portions of the brain (labelled Specimen XXXI.).
(b) Portions of spinal cord (labelled Specimen XXIV.).
Both were in excellent condition as regards fixation and hardening, having been preserved for many years in a fluid composed of formol and 95 per cent. alcohol (the fluid was also injected into the cerebral vessels). They were, previous to histological examination, submitted to the following processes:—
i. Comparatively thin slices were taken from various regions and placed for twenty-four hours in absolute alcohol.
ii. Then transferred to acetone for twelve hours.
iii. Placed in xylol until permeated.
iv. Embedded in paraffin of melting-point 52° C. Sections were then taken with an improved form of the Cambridge rocking microtome, and fixed to slides by means of the albumen method.