SPECIAL EXPRESSIONS: CHAP. V. or in any way excited, rapidly and incessantly move their eyebrows up and down, as well as the hairy skin of their foreheads.15 ..'\As we associate in the case of man the rais- ing and lowering of the eyebrows with definite states of the mind, the almost incessant movement of the eye- brows by monkeys gives them a senseless expression. I once observed a man who had a trick of continually rais- ing his eyebrows without any corresponding emotion, and this gave to him a foolish appearance; so it is with some persons who keep the corners of their months a lit- tle drawn backwards and upwards, as if by an incipient smile, though at the time they are not amused or pleasccjc A young orang, made jealous by her keeper attending to another monkey, slightly uncovered her teeth, and, uttering a peevish noise like tisk-shist, turned her back on him. Both orangs and chimpanzees, when a little more angered, protrude their lips greatly, and make a harsh barking noise. A young female chimpanzee, in a violent passion, presented a curious resemblance to a child in the same state. She screamed loudly with widely open mouth, the lips being retracted so that the teeth were fully exposed. She threw her arms wildly about, sometimes clasping them over her head. She rolled on the ground, sometimes on her back, sometimes on her bclty, and bit everything within reach. A young gibbon (Hylolates syndactylus] in a passion has been described10 as behaving in almost exactly the same manner. The lips of young orangs and chimpanzees are pro- truded, sometimes to a wonderful degree, under various circumstances. They act thus, not only when slightly angered, sulky, or disappointed, but when alarmed at 18 Brelim remarks (^Thierleben,' s. 68) that the> eyc- ."brows of the Inuus ecaudatus are frequently moved up and down when the animal is angered. 18 G-. Bennett, 'Wanderings in New South Wales,' &c. vol. ii. 1834. -n. 153.