100 CONSCIOUSNESS AND SENSATION. 
tained to be the organs without which none of at 
least the higher acts of consciousness can be per- 
formed, are a pair of highly corrugated vesicles, 
closely connected one with the other, and continu- 
ous with the rest of the brain by the lower margins 
of the inlets into the cavities of the vesicles, where 
are situated the corpora striata. The structure 
throughout the different lobes and convolutiors of 
the hemispheres, notwithstanding minor differences, 
is fundamentally the same. Their grey matter con- 
sists of strata of nerve-corpuscles and nucleated pro- 
toplasm, and the vast majority of the corpuscles are 
connected with fibres ascending from the corpora 
striata and with others which lie horizontally, that 
is, parallel to the surface, while they send another 
stronger process perpendicularly outwards. The 
horizontal fibres exist throughout the thickness of 
the grey matter, but are massed particularly in 
a varying number of strata, while others of them ' 
coat the surface in various places. We have thus 
an arrangement fitted to allow consentaneous 
action of the whole grey matter of the hemisphere, 
but nothing pointing to different functions of the 
different regions. The convolutions are accounted 
for when it is considered that they bring the 
vascular supply within easy reach of every part 
of the grey matter, and the minor differences of 
