18 The American Naturalist. [January, 



In this spirit, let us drop our speculations for a moment, and 

 look at some of the commonest phenomena of plant life as 

 they transpire all about us. We shall find that, for all we can 

 see, most plants start equal, but eventually become unequal. 

 It is undoubtedly true that every plant has individuality from 

 the first, that is, that it differs in some minute degree from all 

 other plants, the same as all animals possess differences of per- 

 sonality ; but these inital individual differences are often en- 

 tirely inadequate to account for the wide divergence which 

 may occur between the members of any brood before they 

 reach their maturity. 



The greater number of plants, as I have said, start practi- 

 cally equal, but they soon become widely unlike. Now, every- 

 one knows that these final unlikenesses are direct adaptations 

 to the circumstances in which the plant lives. It is the effort 

 to adapt itself to circumstances which gives rise to the varia- 

 tion. The whole structure of agriculture is built upon this 

 fact. All the value of tillage, fertilizing and pruning lies in 

 the modification which the plant is made to undergo. Ob- 

 serve, if you will, the wheat fields of any harvest time. Some 

 fields are " uneven," as the farmers say ; and you observe that 

 this unevenness is plainly associated with the condition of the 

 land. On dry knolls, the straw is short and the plant early ; 

 on moister and looser lands, the plant is tall,later,withlong, well- 

 filled heads ; on very rich spots, the plants have had too much 

 nitrogen and they grow too tall and " sappy," and the wheat 

 " lodges " and does not fill. That is, the plants started equal, 

 but they ended unequal. Another field of wheat may be very 

 uniform throughout; it is said to be "a good stand," which 

 only means, as you can observe for yourself, that the soil is 

 uniform in quality and was equally well prepared in all parts. 

 That is, the plants started equal, and they remained equal be- 

 cause the conditions were equal. Every crop that was ever 

 grown in the soil enforces the same lessons. We know that 

 variations in plants are very largely due to diverse conditions 

 which arise after birth. 



All these variations in land and other physical conditions 

 are present in varying degrees in wild nature, and we know 



