Spencer 227 



into the organism by the new function, nor consequently 

 with any new physical or chemical or biological character 

 which the organism has now for the first time acquired; 

 but on the contrary there is involved only a different dis- 

 tribution of already existing qualities of matter. But 

 how can a change of quality in imaginary physiological 

 units, which would have proceeded uniformly in the 

 whole organism, accord with the fact that all the qualities 

 and properties of this organism remain unaltered, and 

 there is merely another distribution of these materials? 



Let us consider as a further example the instinct of 

 new born chickens. "In the first minutes of life," writes 

 Jastrow, "chickens follow with their eyes the movements 

 of crawling insects, turning their heads with the precision 

 of an old fowl. In from two to fifteen minutes they 

 pecked at some speck or insect, showing not merely an 

 instinctive perception of distance but an original ability 

 to judge, to measure distance with something like in- 

 fallible accuracy. A chicken hooded as it emerged from 

 the shell was unhooded when three days old ; six minutes 

 later it followed with its head and eyes the movements of 

 a fly twelve inches distant, and about ten minutes later 

 made a vigorous dart at the fly, seized and swallowed it 

 at the first stroke." 173 



Spencer would rightly attribute this instinct to the 

 long practice acquired by the ancestors of the chicken. 

 But if he wished to explain this inheritance through the 

 alteration of specific physiological units of the entire 

 organism, such an explanation would not be taken ser- 

 iously. How could the new physiologic units, capable 

 of effecting this local modification constituted by the 



17S Jastrow: The Problems of Comparative Psychology. The 

 Popular Science Monthly. New-York. Nov. 1892. P. 3637. 



