THE INFANCY OF ANIMALS 



ment is superseded by the much more effective fashion 

 of conveying the milk to the mouth by means of a teat. 

 That is to say, a concentration of the milk-secreting area 

 of the skin has taken place. But the young kangaroo is, 

 so to speak, prematurely born, and 

 has to be attached to the teat by 

 the parent ; and when once this 

 feat has been accomplished it re- 

 tains it within its mouth un- 

 ceasingly, tiU development has far 

 advanced, and the milk is periodi- 

 cally squirted down its throat by 

 the muscular actipn of the parent. 

 This is probably an involuntary 

 action determined by the stimulus 

 NEWLY-BORN KANGAROO Set up when the milk glands be- 

 ATTACHED TO THE TEAT come Surcharged. 



OF THE PARENT. -r. , i n i 



But the bald statement of these 

 facts leaves untouched a whole series of inexplicable 

 happenings, though they are by common consent 

 regarded as explained by the blessed word " instinct." 

 It is this mysterious impulse which directs the mother, 

 untaught, how to dispose of the barely tangible scrap 

 of life which she has produced, and this same impulse 

 which causes the young to open its mouth to grasp 

 the teat. Between these patent facts and the obscure, 

 nebulous, directing force behind them — the " instincts " 

 — there is an intimacy of relationship which means life 

 or death to the race. Instinct and its twin brother 

 Intelligence are the guardian angels of life : subtle, in- 

 tangible, all-pervading, protean. 



Among the mammals, it is to be remarked, it is the rule 

 fhat the young should enter the world in a helpless coii- 



