OBJECTIONS TO THE THEORY 293 



It will indeed be thought that I have an overweening con- 

 fidence in the principle of natural selection, when I do not 

 admit that such wonderful and well-established facts at once 

 annihilate the theory. In the simpler case of neuter insects 

 all of one caste, which, as I believe, havelbeen rendered dif- 

 ferent from the fertile males and females through natural 

 selection, we may conclude from the analogy of ordinary 

 variations, that the successive, slight, profitable modifications 

 did not first arise in all the neuters in the same nest, but in 

 some few alone ; and that by the survival of the communities 

 with females which produced most neuters having the ad- 

 vantageous modification, all the neuters ultimately came to be 

 thus characterized. According to this view we ought occa- 

 sionally to find in the same nest neuter insects, presenting 

 gradations of structure; and this we do find, even not rarely 

 considering how few neuter insects out of Europe have been 

 carefully examined. Mr. F. Smith has shown that the neuters 

 of several British ants dififer surprisingly from each other in 

 size and sometimes in colour; and that the extreme forms can 

 be linked together by individuals taken out of the same nest: 

 I have myself compared perfect gradations of this kind. It 

 sometimes happens that the larger or the smaller sized 

 workers are the most numerous ; or that both large and small 

 are numerous, whilst those of an intermediate size are scanty 

 in numbers. Formica flava has larger and smaller workers, 

 with some few of intermediate size ; and, in this species, as 

 Mr. F. Smith has observed, the larger workers have simple 

 eyes (ocelli), which though small can be plainly distinguished, 

 whereas the smaller workers have their ocelli rudimentary. 

 Having carefully dissected several specimens of these 

 workers, I can affirm that the eyes are far more rudi- 

 mentary in the smaller workers than can be accounted 

 for merely by their proportionally lesser size ; and I fully 

 believe, though I dare not assert so positively, that the workers 

 of intermediate size have their ocelli in an exactly inter- 

 mediate condition. So that here we have two bodies of sterile 

 workers in the same nest, differing not only in size, but in 

 their organs of vision, yet connected by some few members 

 in an intermediate condition. I may digress by adding, that 

 if the smaller workers had been the most useful to the com- 



