Bees and the Origin of Flowers. 



By G. W. Bulman, M.A., B.Sc. 



Those engaged in the study of the mutual relations of insects and 

 flowers will read with interest a short paper in Natural Science for 

 October last on " Bees and the Development of Flowers," by Mr. F. W. 

 Headley, Haileybury College, New Zealand. It is to be feared, how- 

 ever, that this writer's attempt to save the situation for Darwinism as 

 regards the origin of flowers will hardly stand the strain of criticism. 

 Mr. Headley admits that the habits of bees in passing freely from 

 variety to variety, or from one nearly allied species to another, will 

 tend rather to retard than promote the development of new species. 

 " Thus it is just where her constancy might seem most needed," he 

 writes, " that it breaks down. When new varieties are arising, the 

 operation of bees comes in to swamp them, if possible, by intercrossing, 

 and so prevent them from developing into species." This, indeed, 

 must be obvious to all. But while giving up the old explanation, 

 Mr. Headley still thinks the colours of flowers must be explicable on 

 Darwinian principles. " A priori" he says, " if it be granted that the 

 Darwinian hypothesis affords a satisfactory explanation of other pheno- 

 mena of the animal and vegetable worlds, it seems unlikely that it 

 should leave the colours of flowers unexplained." This is doubtless 

 true, and if the origin of species is due to the Darwinian principle of 

 natural selection, then the colours of flowers must be due to the same. 

 To stop the gap, then, caused in the theory of the origin of flowers by 

 insect agency by the loss of the constancy of the bee, Mr. Headley 

 takes a plank from Dr. Eomanes' doctrine of physiological selection. 

 The action of the bee, he thinks, in carrying pollen from variety to 

 variety will be of no consequence, since these varieties are sterile 

 inter se ; while in carrying it from individual to individual of the 

 same species it will still give an advantage to those it visits. As 

 proof of this sterility between varieties of wild-flowers the experiments 

 of the French botanist, Alexis Jordan, quoted by Eomanes in " Darwin 

 and after Darwin," vol. iii., are referred to. But even admitting 

 that Jordan proved his case, we have still the following objections to 

 bring forward. If the bee visits indifferently all the varieties of a 



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