SELECTION 461 



residue of the unattractive. He also pointed out that the 

 more vigorous and more attractive males would be accepted 

 by the more vigorous females which are the first to breed, 

 and this would imply a cumulative preponderance of the 

 more vigorous and more attractive types. Even earlier hatch- 

 ing of the young birds might .be of critical moment. As a 

 matter of fact, definite information as to the elimination 

 of some of the males is by no means wholly lacking. Thus 

 in diagrammatic illustration we may refer to some spiders 

 where, as the Peckhams and others have shown, the female 

 sometimes kills a suitor who does not adequately please her. 

 That she may also kill a successful suitor is immaterial, 

 since the mating has been accomplished. (See G. W. and 

 E. G. Peckham, Observations on Sexual Selection in Spiders 

 of the Family Attidce, Milwaukee, 1889, p. 60.) 



In the second place, many critics have objected to credit- 

 ing the female organism whether bird or butterfly with 

 the power of ' choice ', and while comparative psychology has 

 not advanced far enough to admit of many definite statements 

 as to the subjective aspect of animal courtship, it may be 

 granted that there is not in the ' choice ' of any female 

 animal much that would correspond to a human weighing 

 of pros and cons. But the point of importance is whether 

 the mating is in any real way selective, preferential, dis- 

 criminative. It has been proved experimentally that insects 

 as well as birds may be selective in their eating: is the same 

 true as regards their mating? It, appears to us that the 

 phenomena of mating recorded by Darwin, by Groos (Play 

 of Animals, 1898), by Cunningham (Sexual Dimorphism, 

 1900), by Pycraft (Courtship of Animals, 1913), and so 

 on, place the reality of some measure of preferential mating 

 beyond doubt. Even if one adopts the modern view that 



