90 AMERICAN SPIDERS 



species among which the females show little hostility to the male 

 before mating and enter actively into the preliminary maneuvers. 

 The description of the courtship of Theridion tepidariorum by 

 Montgomery illustrates the general habit of the whole genus. 



The introductory steps of the mating are as often made by the 

 female as by the male, and she often shows quite an insatiable 

 eagerness, even sometimes leaving food to approach the male. As 

 soon as the male commences to move upon her web she recog- 

 nizes him as a male of her own species, and, when she is eager, 

 commences immediately to signal to him, both spiders being on 

 the lower surface of the web and upside down (the usual posi- 

 tion). The female hangs to the web with the third and fourth 

 pairs of legs, and shakes the longer second and first pairs vigor- 

 ously and spasmodically in the air (when those legs are not at- 

 tached to web lines), otherwise with them she shakes web lines 

 to which they are hooked. This 'signalling' is a sign of eagerness 

 on the part of the female, and so far as I have observed she makes 

 it at no other time than when she is eager and notices the ap- 

 proach of a male of her own species. There are individual dif- 

 ferences in the mode of signalling, as well as differences in 

 accord with the degree of eagerness of the female; sometimes a 

 female signals without moving from her original position, some- 

 times with the signalling she moves by short steps towards the 

 male. When she is not eager she either remains motionless, or 

 else rushes hostilely toward the male as at an object of prey; in 

 both cases the male makes no advances, and when she is mark- 

 edly aggressive he escapes by dropping from the web. The 

 whole attitude of the male is that of combined timidity and 

 eagerness; he is much smaller than the female and upon a foreign 

 web, and usually acts with great caution. 18 



In this species the female may mate with many males and, except 

 when heavy with eggs, rarely rejects the advances of a suitor. 

 Whereas the male usually leaves hurriedly after mating, in some 

 species of this group he moves to one side of the web, refills his 

 palpi with semen, and returns to mate frequently. Among the sheet 

 weavers of the family Linyphiidae, the male is also a privileged con- 

 sort and is only rarely menaced by an intractable female. 



18 T. H. Montgomery, "Studies on the Habits of Spiders, Particularly 

 Those of the Mating Period," Proc. Acad. Nat. Set., Philadelphia, 1903, p. 

 104. 



