ii8 Journal of Comparative Neurology. 



apace. It must be remembered that the element which to us as 

 on-lookers chiefly affords amusement i.e. the sense of the incon- 

 gruous — the knowledge that every nicrement of effort in pursuit 

 simply accellerates the flying tail, is absent to puss herself, she 

 finds her enjoyment simply in the pursuit. This may be re- 

 garded as a simple case where a vital impulse is guided by a 

 single easily e.xplicable instinct. As the kitten grows older a 

 habit of play is formed which serves to perpetuate the playful 

 chase after its futility is more or less distinctly recognized by 

 obscure or implicate judgements. In the demure matronly cat 

 of experience such instincts are prevented by a variety of cir- 

 cumstances, ist. the necessary duties of life remove the surplus 

 vitality, 2d. the actual excitement of the chase is so much 

 greater that it serves to depreciate the play exercise by contrast, 

 3d. some vague judgment of the incongruousness of the occupa- 

 tion may be felt just as a certain feeling of shame or "crestfal- 

 lenness"is obvious when puss oversprings her prey. Occasionally, 

 however, even sedate Grimalkin gives way momentarily to the 

 impulse and it is amusing to see the sheep's eyes she makes 

 when caught in her play. It would seem that she feels a genuine 

 sense of incongruousness. Of course this is a point about which 

 it is impossible to be very confident but I appeal to observers of 

 the cat if such be not the appearance. We have so far employed 

 the simplest and most familiar illustrations. It is obvious, 

 however, that all instincts — all hereditary tendencies may in- 

 fluence the playful activities. 



The pursuit of prey, as we have seen, is one of those activ- 

 ities which through heredity becomes instinctive in predaceous 

 animals and thus becomes a determining factor in the develop- 

 ment of playful habits. It should be instructive in this 

 connection to compare the exhibitions of playfulness in the 

 non predaceous groups with those already referred to. 

 Observing the various groups of rodents, herbivora, etc. we are 

 struck with the fact that their sportive movements are of a more 

 rudimentary sort than those of the carnivora, consisting of more 

 or less aimless gambols rather than the pursuit of moving objects. 

 In other words the instinct of the chase is absent unless it be in 

 its obverse expression. 



Young guinea pigs or older individuals when liberated from 



