Chap. V. MONKEYS. 131 



see in the following chapters, the different races of man 

 express their emotions and sensations with remarkable 

 uniformity throughout the world. Some of the expres- 

 sive actions of monkeys are interesting in another way, 

 namely from being closely analogous to those of man. As 

 I have had no opportunity of observing any one species 

 of the group under all circumstances, my miscellaneous 

 remarks will be best arranged under different states of 

 the mind. 



Pleasure, joy, affection. — It is not possible to distin- 

 guish in monkeys, at least without more experience than 

 I have had, the expression of pleasure or joy from that 

 of affection. Young chimpanzees make a kind of bark- 

 ing noise, when pleased by the return of any one to whom 

 they are attached. When this noise, which the keepers 

 call a laugh, is uttered, the lips are protruded; but so 

 they are under various other emotions. Nevertheless 

 I could perceive that when they were pleased the form 

 of the lips differed a little from that assumed when they 

 were angered, If a young chimpanzee be tickled — and 

 the armpits are particularly sensitive to tickling, as in 

 the case of our children, — a more decided chuckling or 

 laughing sound is uttered; though the laughter is some- 

 times noiseless. The corners of the mouth are then 

 drawn backwards; and this sometimes causes the lower 

 eyelids to be slightly wrinkled. But this wrinkling, 

 which is so characteristic of our own laughter, is more 

 plainly seen in some other monkeys. The teeth in the 

 upper jaw in the chimpanzee are not exposed when they 

 utter their laughing noise, in which respect they differ 

 from us. But their eyes sparkle and grow brighter, as 

 Mr. W. L. Martin, 10 who has particularly attended to 

 their expression, states. 



10 ' Natural History of Mammalia,' 1841, vol. i. pp. 383, 

 410. 



