THE PLAY OF ANIMALS. 193 



extraordinary importance of imitation in development. 

 He mentions the case of a mongrel dog that was placed 

 with some St. Bernards when only twenty days old, and 

 says: " One of the features of development greatly im- 

 pressed on my mind . . . was the influence of one on 

 another in all the lines of development. This was shown 

 both negatively and positively in the case of the mon- 

 grel. After he began to mingle with the older dogs 

 his progress was marvellous. He seemed in a few 

 days to overtake himself, so to speak, and his advance- 

 ment was literally by leaps and bounds.'^ * The pro- 

 pensity of young bears to imitate their elders is often 

 taken advantage of by tamers. Brehm gives an interest- 

 ing description by K. Miiller of the education of young 

 stone martens: " The mother is most attentive to the 

 exercising of her young, as I have had occasion to no- 

 tice several times. In the park a wall five metres high 

 is connected with the shed where a pair of martens 

 with four young ones are housed. At daybreak the 

 mother crept out cautiously, stealing like a cat some 

 distance along the wall and crouched there, quietly 

 waiting. There the father joined her, but it was some 

 moments before the young ones came out. When they 

 were all together the parents rose and in five or six 

 bounds covered a considerable stretch of the wall and 

 vanished, and I heard, though it was scarcely audible, 

 the sound of a spring into the garden. The little ones 

 followed with hurried leaps and climbed up on the 

 wall with the aid of a poplar tree growing near. Hard- 

 ly had they reached their parents when the latter sprang 

 away again, this time to a lilac bush, and now the young 

 ones followed them without hesitation. It was aston- 



* Loc. cit., part ill, p. 219. 



