384 THE DESCENT OF MAN 



Bombus as well as in Apathus, much more variable in color 

 than the females. In Anthrophora retusa the male is of a rich 

 fulvous-brown, while the female is quite black; so are the 

 females of several species of Xylocopa, the males being 

 bright yellow. On the other hand, the females of some 

 species, as of Andrcena fulva, are much brighter-colored 

 than the males. Such differences in color can hardly be 

 accounted for by the males being defenceless and thus 

 requiring protection, while the females are well defended 

 by their stings. H. Miiller," who has particularly attended 

 to the habits of bees, attributes these differences in color in 

 chief part to sexual selection. That bees have a keen per- 

 ception of color is certain. He says that the males search 

 eagerly and fight for the possession of the females; and he 

 accounts through such contests for the mandibles of the 

 males being in certain species larger than those of the fe- 

 males. In some cases the males are far more numerous than 

 the females, either early in the season, or at all times and 

 places, or locally; whereas the females in other cases are 

 apparently in excess. In some species the more beautiful 

 males appear to have been selected by the females, and in 

 others the more beautiful females by the males. Conse- 

 quently, in certain genera (Miiller, p. 42), the males of the 

 several species differ much in appearance, while the females 

 are almost indistinguishable; in other genera the reverse 

 occurs. H. Miiller believes (p. 82) that the colors gained 

 by one sex through sexual selection have often been trans- 

 ferred in a variable degree to the other sex, jast as the 

 pollen-collecting apparatus of the females has often been 

 transferred to the male, to whom it is absolutely useless." 



" "Anwendung der Darwin'schen Lehre auf Bienen," "Verh. p. n. Jahrg.," 



" M. Perrier in his article, "La Selection sexuoUe d'apr^s Darwin" ("Eeviie 

 Soientifique," Feb. 1873, p. 868), without apparently having reflected much on 

 the subject, objects that as the males of social bees are known to be produced 

 from unfertilized ova, tEey could not transmit new characters to their male off- 

 apring. This is an extraordinary objection. A female bee fertilized by a male, 

 which presented some character facilitating the union of the sexes, or rendered 

 him more attractive to the female, would lay eggs which would produce only 



