2o6 THE WONDER OF LIFE 



Now these germinal variations, whose origin is another 

 story, find expression at all levels. A person may be 

 born with a chemical variation of such a sort that even 

 a small quantity of egg in his food acts like a poison. 

 Another may be born with some variation in the eye which 

 leads to short-sightedness, colour-blindness, night-blind- 

 ness, or the like. Another has a quite unusual sense of 

 locality or direction. Another is a musical genius. In 

 short, organisms may be born with all manner of constitu- 

 tional variations which lead them to respond in an unusual 

 maimer to external stimuli. The theory of instinct to 

 which Weismannism, for instance, leads, is that instincts 

 arise from within as germinal variations, that those which 

 are profitable survive, while those that are very disadvanta- 

 geous (like some reversionary instincts in man) lead to 

 the death of their possessor. Instincts, as M. Marquet 

 has well said, are ' inborn inspirations '. Their origin is 

 confessedly obscure — from within the creative germ- 

 plasm — but not any more obscure than that of many other 

 inborn variations, such as any form of genius, or any novel 

 departure in detailed structure. 



Experiments on Instinct. — The next step was the 

 establishment of the experimental study of instinctive be- 

 haviour, which we may associate in particular with the name 

 of Lloyd Morgan. Spalding had indeed followed the same 

 method many years before, but his observations were 

 somewhat lacking in exactness. What Lloyd Morgan did 

 was to incubate the eggs of fowls and some other birds 

 in the laboratory, so that he could study the behaviour 

 of the young away from any influence of parental education. 

 He was in this way able to demonstrate the instinctive 

 character of some capacities, such as uttering a character- 



