RELATING TO SECONDARY SEXUAL CHARACTERS. 55 



The mating behavior of Saitis pulex, a species in which the males 

 and females are much alike, is described by the Peckhams as follows : 



" On May 24th we found a mature female and placed her in one of the larger 

 boxes, and the next day we put a male in with her. He saw her as she stood 

 perfectly still, twelve inches away; the glance seemed to excite him and he at 

 once moved toward her; when some four inches from her he stood still and 

 then began the most remarkable performances that an amorous male could 

 offer to an admiring female. She eyed him eagerly, changing her position 

 from time to time so that he might be always in view. He, raising his whole 

 body on one side by straightening out the legs, and lowering it on the other by 

 folding the first two pairs of legs up and under, leaned so far over as to be in 

 danger of losing his balance, which he only maintained by sidling rapidly 

 toward the lowered side. The palpus, too, on this side was turned back to 

 correspond to the direction of the legs nearest it. (Fig. 13.) He moved in a 

 semi-circle for about two inches and then instantly reversed the position of the 

 legs and circled in the opposite direction, gradually approaching nearer and 

 nearer to the female. Now she dashes toward him, while he, raising his first 

 pair of legs, extends them upward and forward as if to hold her off, but withal 

 slowly retreats. Again and again he circles from side to side, she gazing 

 toward him in a softer mood, evidently admiring the grace of his antics. This 

 is repeated until we have counted 111 circles made by the ardent little male. 

 Now he approaches nearer and nearer and when almost within reach whirls 

 madly around and around her, she joining and whirling with him in a giddy 

 maze. Again he falls back and resumes his semi-circular motions, with his 

 body tilted over; she, all excitement, lowers her head and raises her body so 

 that it is almost vertical; both draw nearer; she moves slowly under him, he 

 crawling over her head, and the mating is accomplished. 



"After they have paired once, the preliminary courtship is not so long. 

 When this same pair mated a second tune, there was no whirling movement, 

 nor did the female lift her body, as at first." (pp. 37-38). l 



The courtship of another species, Dendryphantes capitatus, in which 

 the sexes are entirely different, is described as follows : 



"The males of capitatus are very quarrelsome, sparring whenever they meet, 

 chasing each other about, and sometimes clinching. It is a very abundant 

 spider with us, so that we often put eight or ten males into a box to see them 

 fight. It seemed cruel sport at first, but it was soon apparent that they were 

 very prudent little fellows, and were fully conscious that 'he who fights and 

 runs away will live to fight another day.' In fact, after two weeks of hard 

 fighting we were unable to discover one wounded warrior. When the males 

 are approaching each other, they hold the first legs up in a vertical direction. 

 Sometimes they drop the body on to one side as they jump about each other. 

 These movement are very quick, and they are always ready for a passage at 

 arms. When courting the females they have another movement. They 

 approach her rapidly until within two to five inches, when they stop and extend 

 the first legs directly forward, close to the ground, the legs being slightly 

 curved with the tips turned up. (Fig. 18). Whether it be intentional or not, 

 this position serves admirably to expose the whole of the bronze and white 

 face to the attentive female, who watches him closely from a little distance. 

 (Fig. 19.) The males also give their palpi a circular movement, much as a 

 person does when washing his hands. As he grows more excited, he lies down 



1 George W. and Elizabeth G. Peckham. Observations on Sexual Selection in Spiders of the 

 Family Attid. Nat. Hist. Soc. of Wisconsin. Vol. I, 1889, pp. 46, 47. 



