The sexual congress of two spiders has been well described by Peck ham, in his paper on sexual selection. "On May 24 we found a mature female, and placed her in one of the larger boxes, with a male. 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 stopped, and then began the most remarkable performance 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 moved in a semicircle for about two inches, and then, instantly reversing the position of his legs, circled in the opposite direction, gradually approaching nearer and nearer to the female. Now she dashes toward liim; while he, raising his first pair of legs, extends them up, and forward, as if to hold her off, at the same time slowly retreating. Again and again he circles from side to side, she gazing at him in a softer mood, and evidently admiring the grace of his antics. This was repeated until we had counted one hundred and eleven circles made by the ardent little wooer. Now he approaches nearer, and nearer, and, when almost within reach, whirls madly round and round her, she joining and whirling with him in the giddy maze. Again he falls back, and resumes his semicircular motions, with his body tilted over. She, all excitement, lowers her head and raises her body so that it almost stands upright. Both draw nearer, she moves slowly under him," and lo, the great, eternal, mysterious, polymorphous act is accomplished.1 ject to the larger treatises of Linmeus, Lister, Hacek el, and especially the "Liebe und Liebes-Leben in der Thierwelt," of Büchner; Finek's "Primitive Love and Love Stories," and Hacker's "Gesang der Vogel," Chap. rv. ' Vid. G. W. Peekham, loc. et*.

1 "A Balloon Making Fly," American Naturalist, Oct., 1899.