same as that of the scratch-reflex in the dog evoked from stimulation
of the flank and back. I had not then, unfortunately read more than
an abstract of the above paper, but if the full account be followed
it will be seen that the various “territories” belonging to all the
former-reflexes are now known as well as the frontiers of a European
Kingdom. All I was able to do with this unusual opportunity of a heavy
sleep in a normal young cat was to verify more roughly Professor
Sherrington’s observations and slightly to extend them _in respect of a
sleeping animal_.
In the course of these observations on a young cat I examined the
various regions of the back and flanks with mechanical stimuli of
different degrees of strength. These were applied during sleep and I
found that it was more often during a moderate than a light or deep
sleep that the following results were shown--chiefly under the stronger
stimuli the tail was raised sharply and swept in a circular way, and
this would be repeated according as the stimulus was applied; but at
the same time there was shown a strong, irregular twitching along the
flank, extending forwards to a point near the level of the shoulder.
This latter reflex would appear to be a reaction on the part of the
panniculus carnosus. Both the reflex of the muscles of the tail
and this of the flanks appear to be connected in their origin with
movements of parasites in their respective territories.
In considering the scratch-reflex in the cat a subtle bit of adjustment
is found. That coarse and simple scratching of its ear, which we see
so often in the cat, must have often astonished us for its vigour and
yet its bloodless character. This action is of course a purposeful
one, for it goes on when the animal is awake. Here if anywhere this
profoundly hedonistic animal shows that for it the laws of comfort
are its laws of conduct. It is clear that there may be two processes
or conditions involved in its bloodless violence. On the one hand the
reflex retractile mechanism of the claws may be kept in abeyance by
another reaction which is pre-potent; on the other, it is a fact that
the hind foot in the cat is furnished with claws which are much blunter
than those of the fore foot. As far as I have been able to examine cats
of different ages I have found the claws of the hind foot more like
the blunt claws of a dog than the familiar sharp claws of the Felidæ.
So in the violent scratching referred to there may be a double reason
associated in the process. As to the difference in the sharpness of the
fore and hind claws it would appear to be remarkably like a transmitted
bit of adaptation initiated and kept in being by use and habit in
progression, for the hind foot in such animals as the cat has a larger
share in this action than the fore foot. But here it is difficult as so
often to assign to selection its possible share of the adjustment.
Public-domain text, read in full here on John Shaqi.
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