136 PROCEEDINGS OF THE ACADEMY OF [Jan., 



which he deposits the semen (Linyphia triangularis, Agalena lahy- 

 rinthica, Tapinopa longidens, Agalena similis, Micrommata virescens. 

 Dictyna benigna, Philoica domestica, Linyphia montana, Cluhiona 

 comta, Lycosa stonei, L. ocreata pulchra, Tegenaria derhami, Dictyna 

 volupis); and sometimes he makes no special sheeting, but deposits the 

 semen upon a strand of the domicile web {Theridium tepidariorum) . 

 In those species where the male does not construct a domicile welj, 

 but lives upon the ground, as in the Lycosidoi and Drassidce, the male 

 always s])ins a small sheeting to catch the drop of semen, and this 

 is his only spinning act during his mature life; species that live in 

 webs also generally construct a special sheeting for the semen. There 

 is no known case of the male charging his palpi by placing them 

 directly against the genital aperture. In order to see this act the 

 observer should remove the male from the female immediately after 

 a completed copulation, one which has exhausted the palpi of the 

 seminal fluid, and watch for an act of sperm-induction ; that is the onl}' 

 time when one may expect it with some certainty. In some species 

 the male may copulate several times, and frecjuently charges his 

 palpi with semen before repeating an act of copulation. 



This is a very wonderful process: the male discharges semen upon 

 a web, takes up this semen into his palpal organs, and with the latter 

 applies the semen to the genital aperture of the female. There are, 

 in a sense, two separate acts of seminal discharge, and at each of them, 

 but most particularly in the second, the male shows very evident 

 gratification. No one, to my knowledge, has endeavored to account 

 for such a double process, which is essentially different from the 

 ''hektocotyly" of Cephalopods. It is definitely determined that the 

 palpi (pedipalpi) of araneids and other arachnids have, in the mature 

 state, no organic connection with the testes or vasa deferentia, that 

 there are no tubes connecting the palpal organs with the organs in 

 which the spermatozoa develop. In the ontogenetic development the 

 palpi appear at first similar to the other extremities, and are separated 

 from the genital aperture by four segments of the cephalothorax, each 

 bearing a pair of appendages. Accordingly there is neither anatomical 

 nor embryological reason for supposing that the palpi ever had been 

 appendages of the genital aperture, which had later moved forward 

 from the region of the genital aperture; they are true thoracic append- 

 ages, and not abdominal. Now the pedipalpi of Limulus in the male 

 terminate each in a large swollen knob, which is used in the copulation 

 as a clasper of the female; and in Limulus the distal end of each of 

 these swollen joints opens to the exterior by a minute aperture, which 



