2 78 POPULAR SCIENCE MONTHLY. 



was smoking and making such movements and sounds as in his experi- 

 ence had attracted attention and caused the smoker to blow in his face. 

 He was often given a lighted cigar or cigarette to test him for imitation. 

 He formed the habit of rubbing it on his back. After doing so he would 

 scratch himself with great vigor and zest. He came to do this always 

 when the proper object was given him. I have recounted all this to 

 show that the monkey enjoyed scratching himself. Yet Jie apparently 

 never scratched himself except in response to some sensory stimulus. 

 He did not with all his experiences of scratching ever get the idea of 

 that act and use it to arouse the delightful act. He was apparently 

 incapable of thinking 'scratch' and so doing. Yet the act was quite 

 capable of association with circumstances with which as a matter of 

 hereditary organization it had no connection. For by taking a certain 

 well-defined position in front of his cage and feeding him whenever he 

 did scratch himself I got him to scratch always within a few seconds 

 after I took that position. 



The fact that monkeys do not possess the human type of ideas must 

 not be taken as evidence that they are no nearer relatives to us mentally 

 than are the other lower animals. On the contrary they occupy an 

 intermediate position in every main psychological feature between 

 mammals in general and the human species. 



The essentials in an inventory of an animal's mental capacities are 

 its sense powers, the kinds of movements it can make and their delicacy, 

 complexity and number, its instincts or the sum of those tendencies to 

 feel and act which it has apart from experience or learning, and its 

 methods of learning or of modifying its behavior to suit the multitudi- 

 nous circumstances of life. In each of these respects the monkeys show 

 kinship with man. 



In point of sense powers they rely little on smell and much on 

 vision. They possess the power of clear, detailed vision which is absent, 

 for instance, in dogs and cats and is so important a possession of man. 

 A monkey will notice a hair on your hand or a pin six feet off. He 

 thus resembles man in what has been universally recognized as the most 

 intellectual of the senses. 



In their motor equipment monkeys possess first of all the muscular 

 coordinations necessary to sustain an upright position and consequently 

 the free use of the fore-limbs. The movements of these fore-limbs are 

 more in number and suited to more complex and varied tasks than are 

 those of lower animals. The attractiveness of the monkey cage in a 

 zoological garden is largely due to the similarity of the monkeys' move- 

 ments and our own. The monkey not only has a body like a man's, but 

 he also uses it like a man. 



Our native tendencies are so metamorphosed by the education of a 

 civilized environment that in adult age they seldom appear in recogniz- 



