No. 1.] SEXUAL SELECTION IN SPIDERS. 47 



he gradually overcomes her opposition. Her change of mood 

 is only brought about after much patient courting on his 

 part. While from three to five inches distant from her he 

 begins to wave his plumy first legs in a way that reminds one 

 of a wind-mill. She eyes him 

 fiercely and he keeps at a proper 

 distance for a long time. If he 

 comes close she dashes at him 

 and he quickly retreats. Some- 

 times he becomes bolder and 

 when within an inch, pauses, . 

 with the first legs outstretched - 

 before him, not raised as is com- 

 mon in other species ; the palpi Fig. ^o.-Zygoballus Uettmi. Position 

 1 iiTi'm , • r I of male approacliing female (from nature, 



also are held stiiiiy out in irontbyL. k.i. 

 with the points together. Again 



she drives him off, and so the play continues. Now the male 

 grows excited as he approaches her, and while still several 

 inches away whirls completely around and around ; pausing, he 

 runs closer and begins to make his abdomen quiver as he stands 

 on tip-toe in front of her. Prancing from side to side, he grows 

 bolder and bolder, while she seems less fierce, and yielding to 

 the excitement lifts up her magnificently iridescent abdomen, 

 holding it at one time vertically and at another sideways to 

 him. She no longer rushes at him, but retreats a little as he 

 approaches. At last he comes close to her, lying flat, with his 

 first legs stretched out and quivering. With the tips of his 

 front legs he gently pats her; this seems to arouse the old 

 demon of resistance, and she drives him back. Again and 

 again he pats her with a caressing movement, gradually 

 creeping nearer and nearer, which she now jjermits without 

 resistance until he crawls over her head to her abdomen, far 

 enough to reach the epigynum with his palpus. 



ZYGOBALLUS BETTINI. 



The sexual differences in this species are well marked. 

 The male has much more silverv white on the face ; the first 



