COURTSHIP OF SPIDERS. 289 



the nature of the pigments is known. Wallace has spoken 

 of the frequent brilliancy of males as due to their greater 

 vitality, and refers the relative plainness common in females 

 to their greater need for protection. Darwin referred the 

 greater decorativeness of males to the fact that those which 

 varied in this direction found favour in the eyes of their 

 mates, were consequently more successful in reproduction, 

 and thus tended to entail brilliancy on their male successors. 

 But we naturally ask how the brilliancy began, and how its 

 enhancement is transmitted to males alone. In the " Evolu- 

 tion of Sex" Professor Geddes and I have recognised that 

 sexual selection may help to establish the brilliancy of males, 

 and that natural selection may help to keep the females 

 plain, but have also sought to associate decorative and other 

 differences between the sexes with the more fundamental 

 qualities of maleness and femaleness. 



I have introduced this subject here, not only because it 

 affords a pleasant interlude in our systematic survey, and 

 because it serves to illustrate the problems of evolution, but 

 also because natural history has lately been enriched 

 by a valuable series of observations on sexual selection in 

 spiders. 



Two American observers, Mr. and Mrs. Peckham, have 

 made a series of studies on the courtship of spiders more 

 careful than any others of the kind. (Occasional Papers of 

 the Natural History Society of Wisconsin. Milwaukee, 1889.) 



They find "no evidence that the male spiders possess 

 greater vital activity ; on the contrary, it is the female that 

 is the more active and pugnacious of the two." They find 

 " no relation, in either sex, between development of colour 

 and activity; the. Lycosidae, which are among the most 

 active of all spiders, having the least colour development, 

 while the sedentary orb-weavers show the most brilliant 

 hues." " In the numerous cases where the male differed 

 from the female by brighter colours and ornamental ap- 

 pendages, these adornments were not only so placed as to 

 be in full view of the female during courtship, but the 

 attitudes and antics of the male spider at that time were 

 actually such as to display them to the fullest extent 

 possible." " The males were much more quarrelsome 

 in the presence of the females, and to a great extent 



