as already explained, there is not the same primâ facie probability of one only (the male) having been selected!
The fact that both the male and female of various birds of this class utter the same cries, and indulge in the same antics, during the nuptial season, is some evidence that either sex tries to please—i.e. courts—the other; for similar actions and utterances must be taken as implying a similar psychology—they are not like colours or markings—and we cannot, therefore, conceive of them as being merely transmitted, by the laws of inheritance, through the male to the female, and having a mental significance only in the case of the former, or conversely. A bad constitution—the result of intemperance—might descend through the father to the temperate daughter; but if the habit of drinking be also inherited, so must the flaw in the character, of which it is the outcome.
If we admit that certain antics (or cries) common to both sexes of certain birds, have had a like origin in the case of either, then, if by such common actions some common beauty is displayed, it is unreasonable to think that this has been acquired through the action of sexual selection in the case of the one sex (the male) and not in the case of the other (the female), for where the psychology and actions are the same, the laws governing them must be the same, and their effects the same.
The above considerations, enforced as they have been by much that I have myself observed, make me doubt whether the view that where any species of bird
