THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 159 



that there is a development of growling in sleep, 

 growling when awake, barking .(incipient as in older 

 dogs) during sleep, probably in dreams, barking simply 

 as an expression of surplus of energy, barking in 

 wantonness, etc., all of which is, like the wagging of the 

 tail, highly characteristic of different psychic states. 



All these modes of expressions are to be witnessed 

 with precisely the same interpretation in older dogs at 

 times, though, of course, generally the meaning of their 

 barking and growling is more definite. But the puppy 

 persists latent in the dog, just as does the boy in the man. 



DREAMING. Mature dogs do undoubtedly dream, 

 and if one may judge by similar use of the voice and 

 like general behaviour, puppies do also. Leaving out 

 of the question the doubtful evidence of growling in 

 sleep, the phenomena reported on the 35th day seem to 

 point to dreaming, for the behaviour of the puppy is 

 very similar to that of the mature dog. 



ANGER. Much of the play of dogs is mimic fighting, 

 even from the first, and I have noted on the 27th day, 

 during play, a very brief but decided exhibition of anger, 

 such as may occasionally be seen among mature dogs, 

 or boys even of eight or nine years of age during rough 

 play. For the moment anger rules, and the extent to 

 which this is the case, and especially the length of time 

 over which it lasts, depends greatly on the breed of the 

 dogs. With terriers very early play at times becomes 

 serious, and later it may so often become fighting that 

 these dogs cannot always with safety be left together. 

 In few respects do the different breeds show their 

 characteristics, or at so early an age, as in this. For 

 a very early case of anger (or was it a mere reflex ? ) 

 see the record of the 17th day, and for a clear case the 

 record of the terriers on the 30th day. 



MEMORY. In a sense all impressions are remembered, 

 i.e. the state of the nervous system, indeed the whole 



