COLOURS PRODUCED BY COURTSHIP 303 



two varieties (compare figs. 65 and 66) : * the niger 

 form, evidently a later development, is much the more 

 lively of the two, and whenever the two varieties were 

 seen to compete for a female, the black one was 

 successful.' It must be admitted that these facts 

 aiford the strongest support to the theory of Sexual 

 Selection. 



I have quoted much from this important paper 

 because, as far as I am aware, it is the only attempt 

 to solve the question by the systematic observation of 

 courtship in a single group of animals. Many other 

 equally interesting and significant cases are also re- 

 corded, and the paper is profusely illustrated with 

 representations of the most characteristic attitudes. 

 As the result of the whole body of observations the 

 authors are of the opinion that * in the Attidce we have 

 conclusive evidence that the females pay close attention 

 to the love dances of the males, and also that they have 

 not only the power, but the will, to exercise a choice 

 among the suitors for their favour.' Eemembering 

 that this conclusion has only been reached in the 

 Attidce by the closest study, I think we may safely 

 explain the smaller confidence with which we can 

 speak of other animals by the want of sufficiently 

 careful and systematic investigation. 



