LOVE DANCES OP SALTIGRADES. 51 



body in such wise as to elevate that side and correspondingly to depress the 

 other. The legs and palpus of the lower side were folded under, and upon 

 these the spider sidled along, moving in a semicircle for about two inches. 

 He then instantly reversed the position of the legs, and circled in the 

 opposite direction, gradually approaching nearer and nearer to the female 

 in the course of these oscillations. 



The female dashed toward him, while he, raising his first pair of legs, 

 extended them upward and forward, as if to hold her off, but withal slowly 

 retreated. Again he began his oscillating movements until one 

 pulex hundred and eleven circles had been counted. The female in 

 the meanwhile gazed toward him, apparently in a softer mood, 

 evidently admiring the grace of his antics. When he had approached 

 almost within reach of her, he whirled madly around and around her, 

 she joining and whirling with him in a giddy maze. He then fell back, 

 and resumed his semicircular motions, with his body tilted over. She, all 

 excitement, lowered her head and raised her body, so that it was almost 

 vertical. The two then drew nearer. The female moved slowly under 

 the male, he crawling over her head, and the mating was accomplished. ^ 



A male of Synagales picata executes his love dance with all his feet 



on the ground. He raises himself on the tips of the six hindermost legs, 



but slightly inclines his head downward by bending his front 



Love ipgg^ their convex surface being always turned forward. His ab- 



ijfl.Tir^ft of • o •/ 



Svna- domen is lifted vertically, so that it is at a right angle to the 

 gales. plane of the cephalothorax. In this position he sways from side 

 to side. After a moment he lowers the abdomen, runs a few 

 stef)s nearer the female, and then tips his body and begins to sway again. 

 Now he turns in one direction, now in another, pausing every few moments 

 to rock from side to side, and to bend his brilliant legs so that she may 

 look full at them. He could not have chosen a better position tlian tlie 

 one he took to make a display, and the observers were impressed by the 

 fact that the attitude taken by the males served perfectly to show off their 

 fine points to the female.'^ 



Marptusa familiaris is an Attus of sombre gray and black colors, that 

 may be frequently found on trees, fences, and like positions in the neigh- 

 borhood of Philadelphia. It is apparently a widely distributed 

 Woomg- gpecies. When the two sexes were placed together, the female 

 . saw the male as he entered at the opposite side of the box, thir- 



familiaris. ^^^^^ inches away. Eyeing him attentively, she slowly changed 

 her position to keep him in sight, and kept her palps moving 

 rapidly, a characteristic action of the species. As the male neared her, 



' Observations on Sexual Selection in Spiders of the Family Attidte. By George W. and 

 Elizabeth G. Peckham. Occasional Papers of the Natural History Society of Wisconsin, 

 Vol. I., 1889. 



^ Idem, page 43. 



