THE ORIGIN OF FLOWERS 207 



dominant. But are the varieties which we plant side by side in our 

 gardens of the kind that are evolved by bees 1 That is to say, are 

 their differences such as will turn the scale for or agcdnst the visits of 

 the bees? If one were less, another more easily seen by the bees; or if 

 one were more fragrant, or had a fragrance more agreeable to bees 

 than the other, the result of the experiment would probably have 

 been very different. 



One more objection has been made. It is said that the bees, 

 although exclusively restricted, both themselves and their descendants, 

 to a diet of flowers, are not so constant to a particular floiver as the 

 theory requires. They do indeed exhibit a 'considerable amount of 

 constancy,' and often visit a large number of flowers of the same 

 species in succession, but the theory requires that they should not 

 only confine themselves to this one species, but to a single variety of 

 this species. These views show that their authors have not penetrated 

 far towards an understanding of the nature of selection. Nature does 

 not operate with individual flowers, but with millions and myriads of 

 them, and not with the flowers of a single spring, but with those of 

 hundreds and thousands of years. How often a particular bee may 

 carry pollen uselessly to a strange flower without thereby lowering 

 the aggregate of seeds so far that the existence of the species seems 

 imperilled, or how often she may fertilize the pistil of a useful varia- 

 tion with the pollen of the parent species, without interrupting or 

 hindering the process of the evolution of the variety, no mortal can cal- 

 culate, and what the theory requires can only be formulated in this way: 

 The constancy of the bees in their visits to the flowers must be so great 

 that, on an average, the quantity of seeds will be formed which sufiices 

 for the preservation of the species. And in regard to the transformation 

 of a species, the attraction which the useful variety has for the bees 

 must, on an average,be somewhat stronger than that of the parent species. 

 As soon as this is the case the seeds of the variety will be formed in 

 preponderant numbers, although they may not all be quite pure from 

 the first, and by degrees, in the course of generations, the plants of the 

 new variety will preponderate more and more over those of the parent 

 form, and finally will alone remain. In the first case we have before 

 our eyes the proof that, in spite of the imperfect constancy of the bees, 

 a sufficient number of seeds is produced to secure the existence of the 

 species. Or does Mr. Bulman conclude from the fact that the bees are 

 not absolutely constant that flowers are not fertilized by bees at all ? 



• I cannot conclude this note without touching briefly upon what 

 the opponents of the flower theory have contributed, and what 

 explanation of the facts they are prepared to ofler. 



