NURTURE VERSUS NATURE 



occasion, seemingly to supplant the power of 

 nature. 



AN IMMIGEANT BHUBARB 



But this very striking demonstration of the 

 modifications in the life history of an organism 

 that may be brought about through changed en- 

 vironment is by no means without precedent. 



Something quite comparable has been ob- 

 served, for example, when the migration has been 

 effected in the opposite direction, the plant being 

 brought from the southern hemisphere to our own 

 northern latitudes. 



The case of the eucalyptus tree, which takes 

 on extraordinary capacities of growth in Califor- 

 nia, is perhaps not to be too greatly emphasized 

 because this tree is also a rapid grower in its 

 native Australian soil. But there are other plants 

 that seem to reveal new possibilities, in particular 

 when brought to California from the southern 

 hemisphere. 



As a typical instance, we may recall Mr. Bur- 

 bank's winter rhubarb. This plant, when Mr. 

 Burbank first imported it from Australia, had a 

 stalk scarcely larger than a lead pencil. The sole 

 value of the plant from an economic standpoint, 

 and the thing that gave it chief interest for Mr. 

 Burbank, was the fact that it had the habit of put- 

 ting forth stalks in cold weather. 



Lower temperature appeared to have the effect 

 of stimulating it, just as high temperatures stimu- 

 late most other vegetables. 



[297] 



