TRANSACTIONS OF SECTION I. 889 
which it takes part is a reflex or no. So that this point is irrelevant. And so it 
might be urged that the one action has as good a title to be called a reflex as the 
other. I do not, however, wish to insist too much on this comparison. I am 
inclined to say, after Touchstone, ‘ An ill-favoured thing, sir, but mine own.’ 
If, as some think is the case, the spinal ganglion cell receives the nerve-impulse 
conveyed by the peripheral nerve process, and modities it before passing it on to 
the central process, this establishes a distinguishing character for the true reflex. 
It would be probably an axon plus dendron reflex, the pseudo-reflex being simply 
an axon reflex. The important known functional difference between the reflex 
and the pseudo-reflex is that in the former case the nerve-endings of the primarily 
affected nerve-fibre are specially differentiated for receiving nerve-impulses, and 
in the latter case these endings are specially differentiated for imparting nerve- 
impulses, And, on the whole, it is probable that the pseudo-reflex is not a normal 
part of the working of the body, but comes into play only as it were by accident. 
T do not, however, regard this as quite certain. 
The pseudo-reflex I have spoken of is caused by the excitation of nerve-fibres 
before they reach the ganglia—z.c. of pre-ganglionic fibres. But the fibres which are 
given off by the ganglia also branch, so that it appears inevitable that we should 
have in certain circumstances an action related to a reflex caused by a stimulation 
set up in one of these branches spreading to the rest—z.e, a spreading out of im- 
ne in post-ganglionic fibres similar to that which occurs in pre-ganglionic fibres. 
urning to the diagram, fig. 1, a nervous impulse set up in one branch—possibly 
by a contraction of muscle-cells to which it rans—would spread to other branches 
and cause contraction of the muscle-cells in connection with them. You will 
notice that this spreading out of impulses does not necessarily involve the stimula- 
tion of any nerve-cell ; it might perhaps be distinguished as ¢rradiation. It would, 
probably, be very local in action, unless there were overlapping of the districts 
supplied by the several nerve-cel]s, in which case a not inconsiderable spreading 
out of a local contraction might take place, giving rise to a peristaltic wave. 
It must be pointed out that it has been assumed that in the sympathetic nervous 
system an impulse cannot pass from a motor fibre through the nerve-cell from 
which the fibre arises and affect any other nerve-fibre or nerve-cell. There is good 
ground for this assumption, but the experimental evidence might certainly be more 
complete. 
o return to our main line of argument, we have good evidence that nervous 
impulses set up in one spot may affect regions more or less remote by a mechanism 
which does not involve the presence in the sympathetic system of special sensory 
nerve-cells with peripheral sensory nerve-endings. And so far as investigation has 
gone at present, I think that all the apparent reflex actions can be explained with- 
out reference to such sensory apparatus. And so I take the analogy of the peri- 
pheral ganglia with the central nervous system to be misleading, and consider that 
all the nerve-cells of which we have been speaking are motor nerye-cells, and 
that they all conform to the simple plan shown in fig. 1. Thus the whole consists 
of a duplication of one type; a cell in the spinal cord which branches, each branch 
ending in a single cell; each of these cells sends off a nerve-fibre which branches, 
the branches ending in a group of involuntary muscle or gland cells. 
That I regard as the real working mechanism, but there are two reservations 
to make. All the tissues of the body may be looked upon as engaged in a life- 
long process of carrying out experiments, and I am prepared to believe that there 
are in the body what may be spoken of as the residues of these natural physiological 
experiments, either the beginnings of experiments which have not succeeded, or 
the melancholy ends of those which once partially successful have failed later. 
Such possibly may be the nerve-cells which have been described in sympathetic 
ganglia as sending their nerve-fibres to other nerve-cells. 
Secondly, in this account I have not included the nerve-cells which exist in the 
wall of the alimentary canal, and the cells of Auerbach’s and Meissner’s plexuses, 
These ‘ enteric’ nerve-cells belong, I hold, to a system different from that of the 
other peripheral nerve-cells. With regard to their connections I do not think 
anything can be said with certainty, 
