206 THE METHOD OF DARWIN. 



Darwin, so far as I know, never recognized it. 

 The earliest clear statement of it that I have 

 seen is by Prof. Joseph Le Conte in an article 

 on "Instinct and Intelligence," 1 published in 

 1875, on ly a f ew months after the publication 

 of Darwin's " Insectivorous Plants. " He said, 

 "Instinct, therefore, is accumulated experi- 

 ence, or knowledge of many generations fixed 

 M permanently and petrified in brain-structure. 

 All such petrifaction arrests development, be- 

 cause unadaptable to new conditions. They are 

 J ound, therefore, only in classes and families 

 J^jJjjy^ widely differentiated from the main stem of evolu- 

 tion, from the lowest animals to man. Instincts 

 are, indeed, the flower and fruit at the end of 

 these widely differentiated branches, but flower- 

 ing and fruiting arrest onward growth." In 

 1877, Marsh, in a discussion of the suilline 

 type, stated the true principle when he said 

 that ambitious offshoots have perished, while 

 the generalized or rather unspecialized forms 

 continue the line of life with true suilline 

 stubbornness. 2 



1 Popular Science Monthly, October, 1875, P- 664. 



2 American Journal of Science, XIV. (III.), pp. 362-364. 



