ON THE CEREBRO-VISCERAL NERVE. 355 
by a slow revolution of the food through the various compart¬ 
ments of the rumen ; and that is accomplished by the alternate 
contraction of the longitudinal, and circular, and oblique muscles, 
for they are not only strong, but they run in every direction. 
Here, too, the successive contraction of the different parts of the 
stomach agitates the alimentary mass, and brings every portion 
of it, in its turn, into contact with the mucous secretion ; and all 
this is effected by no spinal motor nerve (for no one can be traced 
to the stomach), but by this cerebro-visceral one, which is seen 
ramifying in every direction under the peritoneal coat. 
A portion of the food which was first received is now, by some 
voluntary effort (the will is not excluded from every part of the 
process), brought over the valve-like projection which separates 
the rumen from the reticulum—the first stomach from the second. 
This pellet being received into the honeycomb, all voluntary 
influence and power for awhile cease, and the cerebro-visceral 
takes up the work ; and it compresses the pellet, and forms it 
into the proper shape to reascend the gullet: and it squeezes 
from its beautifully arranged cells a viscid fluid with which the 
pellet is enveloped ; and then by an act partly voluntary, or in 
which (and that is the essence of our system) many voluntary 
muscles are brought to lend their aid to the involuntary or 
organic ones, the pellet breaks through the floor of the canal, 
and by the same mingled influence reascends the oesophagus ; 
is subjected to a second mastication; and is once more 
swallowed ; and, being reduced to a semifluid form, has no longer 
sufficient momentum to break through the cesophagean canal, 
but passes on to the third stomach. 
There again the cerebro-visceral acts, and acts exclusively. 
The food has been twice masticated, but there may remain some 
hard fibres which would resist the solvent power of the gastric 
juice. These are taken up by the leaves of the manyplus, and 
a new action commences—a triturating grinding motion : the 
animal is not conscious of it; it is a purely organic affair; 
and these fibres are mechanically rubbed down between the 
roughened papillated leaves of the manyplus. In accordance 
with this, there are here, compared with the size of the stomach, 
muscular fibres ten times stronger than in the paunch, and there 
are far more abundant ramifications from the cerebro-visceral 
nerve. 
The food is at length prepared for digestion, and enters the 
fourth or true stomach; and there is the muscular action of the 
parietes of the stomach, and all its effects, as I have just de¬ 
scribed in the horse. I have dwelled at considerable, I trust 
not tedious, length on this part of my subject, for the stomachs 
