CHAP. IV. LYTHRUM SALICAEIA. 163 



It would thus appear as if the male organs of the 

 mid-styled form, though not as yet rudimentary, were 

 tending in this direction. On the other hand, the 

 female organs of this form are in an eminently efficient 

 state, for the naturally fertilised capsules yielded a 

 considerably larger average number of seeds than 

 those of the other two forms almost every flower 

 which was artificially fertilised in a legitimate manner 

 produced a capsule and most of the illegitimate 

 unions were highly productive. The mid-styled form 

 thus appears to be highly feminine in nature; and al- 

 though, as just remarked, it is impossible to consider 

 its two well-developed sets of stamens which produce 

 an abundance of pollen as being in a rudimentary 

 condition, yet we can hardly avoid connecting as 

 balanced the higher efficiency of the female organs in 

 this form with the lesser efficiency and lesser size of its 

 two kinds of pollen-grains. The whole case appears 

 to me a very curious one. 



It may be observed in Tables 23 to 25 that some 

 of the illegitimate unions yielded during neither year 

 a single seed ; but, judging from the long-styled plants, 

 it is probable, if such unions were to be effected re- 

 peatedly by the aid of insects under the most favour- 

 able conditions, some few seeds would be produced in 

 every case. Anyhow, it is certain that in all twelve 

 illegitimate unions the pollen-tubes penetrated the 

 stigma in the course of eighteen hours. At first I 

 thought that two kinds of pollen placed together on 

 the same stigma would perhaps yield more seed than 

 one kind by itself; but we have seen that this is not 

 so with each form's own two kinds of pollen; nor is it 

 probable in any case, as I occasionally got, by the use 

 of a single kind of pollen, fully as many seeds as a 

 capsule naturally fertilised ever produces. Moreover 



