208 ILLEGITIMATE OFFSPRING OF CHAP. V. 



in the first four classes were completely fertile; one, 

 however, was nearly so, yielding 96 per cent, of the 

 proper number of seeds. From this high degree of 

 fertility we have many descending gradations, till we 

 reach an absolute zero, when the plants, though bear- 

 ing many flowers, did not produce, during successive 

 years, a single seed or even seed-capsule. Some of the 

 most sterile plants did not even yield a single seed 

 when legitimately fertilised with pollen from legiti- 

 mate plants. There is good reason to believe that the 

 first seven plants in Classes I. and II. were the offspring 

 of a long-styled plant fertilised with pollen from its 

 own-form shortest stamens, and these plants were the 

 most sterile of all. The remaining plants in Classes I. 

 and II. were almost certainly the product of pollen 

 from the mid-length stamens, and although very ster- 

 ile, they were less so than the first set. None of the 

 plants in the first four classes attained their full and 

 proper stature; the first seven, which were the most 

 sterile of all (as already stated), were by far the most 

 dwarfed, several of them never reaching to half their 

 proper height. These same plants did not flower at 

 so early an age, at so early a period in the season, 

 as they ought to have done. The anthers in many of 

 their flowers, and in the flowers of some other plants 

 in the first six classes, were either contabescent or 

 included numerous small and shrivelled pollen-grains. 

 As the suspicion at one time occurred to me that the 

 lessened fertility of the illegitimate plants might be 

 due to the pollen alone having been affected, I may 

 remark that this certainly was not the case; for several 

 of them, when fertilised by sound pollen from legiti- 

 mate plants, did not yield the full complement of 

 seeds; hence it is certain that both the female and 

 male reproductive organs were affected. In each of 



