92 AMERICAN SPIDERS 



The need for any courtship in such animated spermatophores should 

 not be very great. 



THE MATING 



The transfer of sperm is accomplished in a most amazing manner 

 by means of the palpus and the epigynum. Whereas in most animals 

 the copulatory act contributes little or nothing to knowledge of the 

 group, in spiders the details are of great interest and in many cases 

 of deep significance. During the mating the female becomes quies- 

 cent and remains in a kind of cataleptic state until its termination. 

 In many species, the female first contributes to the mating by align- 

 ing parts of the epigynum so that the corresponding units of the 

 male palpus can be properly oriented. The attitude maintained by 

 the sexes is most constant within the species, and the details some- 

 times give us data on the general position of the spiders of the series. 



Two principal embraces are found among spiders. In the taran- 

 tulas, the six-eyed spiders, and the aerial web spinners, the male 

 usually approaches the female from in front, and, moving under- 

 neath until his cephalothorax lies beneath her sternum, applies his 

 palpi directly. This is frequently referred to as the Dysdera em- 

 brace. Among the web spiders it is a quite favorable position, since 

 the female hangs inverted below the male and does not greatly 

 menace him. On the other hand, the male wandering spiders that 

 use this type of embrace are in a dangerous situation beneath the 

 jaws of the female. Retreat after the mating, when the female has 

 largely lost her sexual ardor, is likely to be hazardous. In many 

 instances, the males carefully disengage themselves and then leap 

 back and away quickly, showing that they have become conditioned 

 to compensate for a changed attitude in their mates. 



The second position, the Lycosa embrace, is the one used by the 

 wolf spiders and the running spiders of the higher families. Here 

 the male crawls over the body of the female, and, with head pointed 

 in the opposite direction from hers, reaches around the side of her 

 abdomen to apply a palpus to the epigynum. There is far less danger 

 to the male when he assumes this position, and he is more or less in 

 command of the female until he disengages the palpus and runs 

 away. He serves the right side of her epigynum with his right 

 palpus, and swings around to the other side when using the left 

 palpus. Some of the vagrants have so modified their bodies that it 

 has been necessary to change the type of embrace. Thus, the ab- 



