As the upper lip is much drawn up during the act of screaming, in the
manner just explained, the depressor muscles of the angles of the mouth
(see K in woodcuts 1 and 2) are strongly contracted in order to keep
the mouth widely open, so that a full volume of sound may be poured
forth. The action of these opposed muscles, above and below, tends to
give to the mouth an oblong, almost squarish outline, as may be seen in
the accompanying photographs. An excellent observer,[605] in describing
a baby crying whilst being fed, says, it made its mouth like a square,
and let the porridge run out at all four corners. I believe, but we
shall return to this point in a future chapter, that the depressor
muscles of the angles of the mouth are less under the separate control
of the will than the adjoining muscles; so that if a young child is
only doubtfully inclined to cry, this muscle is generally the first to
contract, and is the last to cease contracting. When older children
commence crying, the muscles which run to the upper lip are often the
first to contract; and this may perhaps be due to older children not
having so strong a tendency to scream loudly, and consequently to keep
their mouths widely open; so that the above-named depressor muscles are
not brought into such strong action.
With one of my own infants, from his eighth day and for some time
afterwards, I often observed that the first sign of a screaming-fit,
when it could be observed coming on gradually, was a little frown,
owing to the contraction of the corrugators of the brows; the
capillaries of the naked head and face becoming at the same time
reddened with blood. As soon as the screaming-fit actually began, all
the muscles round the eyes were strongly contracted, and the mouth
widely opened in the manner above described; so that at this early
period the features assumed the same form as at a more advanced age.
Dr. Piderit[606] lays great stress on the contraction of certain
muscles which draw down the nose and narrow the nostrils, as eminently
characteristic of a crying expression. The _depressores anguli oris_,
as we have just seen, are usually contracted at the same time, and they
indirectly tend, according to Dr. Duchenne, to act in this same manner
on the nose. With children having bad colds a similar pinched
appearance of the nose may be noticed, which is at least partly due, as
remarked to me by Dr. Langstaff, to their constant snuffling, and the
consequent pressure of the atmosphere on the two sides. The purpose of
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