_Anger_. This emotion is often exhibited by many kinds of monkeys, and
is expressed, as Mr. Martin remarks,[513] in many different ways. Some
species, when irritated, pout the lips, gaze with a fixed and savage
glare on their foe, and make repeated short starts as if about to
spring forward, uttering at the same time inward guttural sounds. Many
display their anger by suddenly advancing, making abrupt starts, at the
same time opening the mouth and pursing up the lips, so as to conceal
the teeth, while the eyes are daringly fixed on the enemy, as if in
savage defiance. Some again, and principally the long-tailed monkeys,
or Guenons, display their teeth, and accompany their malicious grins
with a sharp, abrupt, reiterated cry. Mr. Sutton confirms the
statement that some species uncover their teeth when enraged, whilst
others conceal them by the protrusion of their lips; and some kinds
draw back their ears. The _Cynopithecus niger_, lately referred to,
acts in this manner, at the same time depressing the crest of hair on
its forehead, and showing its teeth; so that the movements of the
features from anger are nearly the same as those from pleasure; and the
two expressions can be distinguished only by those familiar with the
animal.
Baboons often show their passion and threaten their enemies in a very
odd manner, namely, by opening their mouths widely as in the act of
yawning. Mr. Bartlett has often seen two baboons, when first placed in
the same compartment, sitting opposite to each other and thus
alternately opening their mouths; and this action seems frequently to
end in a real yawn. Mr. Bartlett believes that both animals wish to
show to each other that they are provided with a formidable set of
teeth, as is undoubtedly the case. As I could hardly credit the reality
of this yawning gesture, Mr. Bartlett insulted an old baboon and put
him into a violent passion; and he almost immediately thus acted. Some
species of Macacus and of Cereopithecus[514] behave in the same manner.
Baboons likewise show their anger, as was observed by Brehin with those
which he kept alive in Abyssinia, in another manner, namely, by
striking the ground with one hand, like an angry man striking the
table with his fist. I have seen this movement with the baboons in the
Zoological Gardens; but sometimes the action seems rather to represent
the searching for a stone or other object in their beds of straw.
Mr. Sutton has often observed the face of the _Macacus rhesus_, when
much enraged, growing red. As he was mentioning this to me, another
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