130 ANIMAL LIFE 



called it forth is removed or even opposed. This 

 faculty of the nervous system has been happily called 

 organic memory- If the conditions of life were un- 

 changing, such a faculty would be unimaginable. 

 But change — secular change — is of the essence of 

 life, and the fuller the life the more generous in num- 

 ber and amplitude of swing are the conditions under 

 which it nourishes. Not only day and night, winter 

 and summer, seedtime and harvest, set going the 

 inward pendulum of animal life, but the life and 

 death of their associates, the swing of the tides, all 

 the great secular movements, beat with alternating 

 force upon the receptive nervous tissue. Upon these 

 leading motives that create habit others are super- 

 imposed. We learn to walk because the brain has 

 learnt to respond without effort along the trodden 

 paths of nervous life, and is free to learn the new 

 ways of upright adjustments. 



Organic Memory an aid to Developmental Study. — 

 It is helpful to remember that once the nervous system 

 has established a periodicity, that then, like a pen- 

 dulum, it will continue to swing without the repetition 

 of the push that started it. For by such a metaphor 

 we are able to picture the development of an animal 

 in a new light. Nothing is more wonderful, nor 

 more familiar, than the moulding of a life in dark- 

 ness, and the gradual revelation of its conduct, at 

 first animal, then racial and traditional, ami, lastly, 

 individual. But if we admit that life preserves a 

 memory of that which it lias long experienced, and 



