166 MR. F. M. CAMPBELL OH THE 



up and down, when, as they touched the palpi of the female, the 

 pair played with these organs like two friendly bees with their 

 antennae. After a few minutes the female raised herself, leaning 

 a little on her left side, and the male crept forward until his head 

 was under the sternum of his mate, while his first pair of legs 

 were resting upon hers. He now advanced his right palpus, 

 leaning a little to the left and using the left palpus as part 

 of his support. The right palpus was slightly twisted so as 

 to bring the surface drawn in fig. 1 opposite the sexual organ 

 of the female, while the joints below the hvimeral were directed 

 obliquely outwards and downwards. The digital joint seemed 

 to lie in such a position that, if moved upwards and forwards, 

 the groove G- (figs. 1 and 2) would come in contact with the 

 right bursa copulatrix, E*, fig. 21. I have but little doubt 

 that the embolos was by this time transferred from its usual 

 resting-place along the rim of the cavity A to the groove Gr 

 (figs. 1 and 2). The male now rapidly raised his palpus up and 

 down for four or more seconds, and with such energy as to 

 compel the female to assume a vertical position. He then re- 

 tired, and again approached her, repeating the movements to a 

 greater or less number, occasionally pausing before he withdrew 

 his palpus witli a slight twist inwards. At times he would leave 

 the female for five minutes, and strut with straightened legs 

 round the vase wagging his abdomen. Now and then be would 

 remain perfectly still with the palpus withdrawn, or play with 

 the palpi of the female while she seemed in a comatose state. He 

 would then renew the union with undiminished vigour, appear- 

 ing on each occasion less desirous of changing his position. I 

 left them at 12.30 a.m. and returned at 7 a.m. The male was 

 still using his right palpus. I saw no application of the left 

 palpus, but have no doubt that it was employed during the night 

 as in other cases. I have not observed the pairing ever inter- 

 rupted by a fresh collection of semen, although there is no 

 reason to think that this may not occur. The duration of the 

 pairing is long ; but I am inclined to think it is more dependent 

 on the difficulty in inserting the embolos than on sexual endu- 

 rance. The impregnation appeared to take place when the 

 male retained his palpus in front of the bursae copulatrices for 

 about thirty seconds, which was frequently the ease, Ausserer, 

 in describing the pairing of Epeira diadema (' Zeitschrift des 

 Ferdinandeums,' Dritte Tolge, pt. xiii. 1867, p. 199), seems to 



