396 
GENERAL SUMMARY 
Part II.. 
through the laws of variation and natural selectioUy 
than to explain the birth of the individual through the 
laws of ordinary reproduction. The birth both of the 
species and of the individual are equally parts of that 
grand sequence of events, which our minds refuse to- 
accept as the result of blind chance. The understand- 
ing revolts at such a conclusion, whether or not we 
are able to believe that every slight variation of struc- 
ture, — the union of each pair in marriage, — the disse- 
mination of each seed, — and other such events, havo 
all been ordained for some special purpose. 
Sexual selection has been treated at great length in 
these volumes ; for, as I have attempted to shew, it has 
played an important part in the history of the organic 
world. As summaries have been given to each chapter, 
it would be superfluous here to add a detailed sum- 
mary. I am aware that much remains doubtful, but I 
have endeavoured to give a fair view of the whole case. 
In the lower divisions of the animal kingdom, sexual 
selection seems to have done nothing; such animals 
are often afiSxed for life to the same spot, or have the 
two sexes combined in the same individual, or what is 
still more important, their perceptive and intellectual 
faculties are not sufficiently advanced to allow of the 
feelings of love and jealousy, or of the exertion of choice. 
When, however, we come to the Arthropoda and Verte- 
brata, even to the lowest classes in these two great Sub- 
Kingdoms, sexual selection has effected much ; and it 
deserves notice that we here find the intellectual facul- 
ties developed, but in two very distinct lines, to the 
highest standard, namely in the Hymenoptera (ants, 
bees, &c.) amongst the Arthropoda, and in the Mam- 
malia, including man, amongst the Vertebrata. 
In the most distinct classes of the animal kingdom, 
