BOT.-VOL. II.] PEIRCE— SEQUOIA SEMPERVIRENS. IO3 



reaction to, certain stimuli. There being no need to man- 

 ufacture food, the food-manufacturing apparatus is not 

 formed, a parasitic habit being successful so far as the 

 individual is concerned, the inherited habit is not entered 

 upon. 



That the need to manufacture food would have an effect 

 upon the development of the white suckers is indicated by 

 the behavior of the white sucker which grew near Gilroy 

 and which 1 planted in my garden where it could obtain 

 little if any organic matter as food. It died soon after 

 transplanting, but not until one leaf had become f ale green. 

 The effect of cutting white suckers away from the parent 

 stock and from their supply of manufactured food I shall 

 test presently by experiment on the redwoods near the La 

 Honda road; but this experience is not without significance. 

 At least it strengthens my contention that inherited tendency 

 is less strong than environment, and that in some cases, at 

 least, inherited tendency must be called into action by some 

 specific stimulus or combination of stimuli operating upon 

 the plant from outside itself. In our white redwoods, the 

 descendants of an exceedingly ancient race of trees in which 

 heredity should be proportionally strong, we have a certain 

 amount of evidence that the irritability and the power of 

 response of the organism to external influences are stronger 

 than its heredity. May not this always be the case? May 

 it not be that what we call heredity is really the response to 

 similar stimuli and combinations of stimuli occurring in 

 orderly succession in the course of nature? 



Stanford University, 

 California, 



June, 1900. 



