No. 519] THE COURTSHIP OF ABASE ADS 



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It is the general rule that the males mature earlier 

 than the females, and the former do not live longer than 

 a year. Promiscuous mating is general, a male im- 

 pregnating a number of females, and a female receiving 

 a number of males. I have seen a female of Geotrecha 

 piunata mating with two males in close alternation, two 

 males of the theridiid Ccruiiuopsis hit cypres embracing 

 a female simultaneously, and I have described (1903) for 

 Theridium tepidariorum as many as twenty-seven im- 

 pregnations of one female. In the attid Phidippus 

 pur pur at us one male was seen by me to fertilize several 

 females. Monogamy is exceptional, and would appear 

 to occur in cases where the male seizes immature females 

 by force, and where the male lives in a mating nest with 

 a female. Many attids make such nests ; in the case of 

 Phidippus purpuratus I have frequently found pairs in 

 such nests in the wild state but never found them to 

 make such nests in captivity, where there is on the 

 contrary promiscuous mating. McCook (1890) has 

 brought together some of the literature on mating nests. 

 In certain cases an adult male seeks out and sequestrates 

 an immature female, mating with her when she matures. 

 The Peckhams (1889) found the only attid under their 

 observation, "in which we saw males take possession of 

 young females and keep guard over them until they 

 became mature," to he Pltihcus militoris. A pair of 

 Drassus neglectus was caught by me in a mating nest 

 on June 16, last, and placed in a cage, where he built 

 another nest around her ; on June 23 he mated with her 

 when she had just finished moulting and was still quite 



