OBTAINING VARIATIONS 109 



the new race of perfected balloon-flowers was 

 evolved. 



Now it remains to add that when the experi- 

 ment was approaching completion, and a new 

 race of balloon-flowers in many ways satisfac- 

 tory was actually in being, I discovered one day 

 among the blossoms one that had a perfectly 

 regular second row of petals, instead of the usual 

 single row, or the irregular so-called double, 

 which had sometimes appeared. Here was an 

 unexpected variation, which was something not 

 specially counted on or considered, but, needless 

 to say, was hailed with delight, and marked for 

 further education. 



If we ask why this second row of petals 

 appeared, the answer can be only a conjecture. 

 Doubtless some condition of altered nutrition 

 stimulated the plant to this abnormal produc- 

 tion. It is customary to speak of such an anom- 

 aly as a "sport" or mutation. But doubtless 

 these words beg the question. They name a con- 

 dition, but do not in any way explain it. 



It is an observed fact, however, that sudden 

 variations analogous to this may be stimulated 

 by a change of climate or a change of soil, as 

 when a plant is brought from another hemi- 

 sphere, or by a surplusage or a shortage of food. 

 It is familiarly known that in a beehive the larva 



