560 PROCEEDINGS OF THE ACADEMY OF [Dec., 



Emerton (I. c.) states (under the name of D. saccatus) : " In the early 

 summer a male and female live together in the nest, the female often 

 being immature." During % June I found several such pairs, as well 

 as males in separate nests, but after that month found no more 

 males. The copulation was observed in two cases. The first instance 

 concerns cT 1510 (an unusually large individual) and 9 1511, found in 

 different nests on 7 June and placed in one cage; he was larger than 

 she. The same day copulation was observed from 5.31-5.38 P.M., 

 one palpus applied at a time, the right three times and the left once, 

 each palpus being held in the epigynum for 1-2 minutes, then with- 

 drawn for about a minute, then the same or the other palpus inserted. 

 He left her at 5.42, but returned two minutes later and inserted the 

 left palpus for 15 seconds, then he left her again and she moved away 

 five minutes later. The position of the two was about the same as 

 in Phidippus. This pair were observed again in mating attitude at 

 3.30 P.M., 24 June, 8.10-8.17 P.M., 25 June, and 9.P.M., 29 June; 

 he died (not eaten by his mate) on 4 July. The other instance was that 

 of d 1 1506 and 9 1507 caught in the one nest on 16 June and placed 

 together in a cage. On 23 June, at 9 A.M., I found him copulating 

 with his right palpus; she had moulted within the preceding half hour, 

 was still soft and near her old exuvia. He kept his right palpus inserted 

 for 39 minutes, and when he withdrew it she struggled away from him. 

 But he found her again, at 9.42 inserted the same palpus for a few 

 seconds, again at 9.46 for a minute, and again continuously from 9.48 

 to 10.25, when I was obliged to leave, and on my return at 11.12 they 

 were separated. Both escaped from the cage before the end of the 

 month. 



This instance of mating with a female just at the time of her moulting 

 is interesting, for it gives the timorous male his opportunity while she 

 is helpless. It is probably full-grown males that seek out still immature 

 females and live with them in the same mating nest. 



Geotrecha crocata (Keys). 



The mating was observed only once, in the case of a female caught 

 3 August, and a male ten days previously, placed together in a small 

 cage on 4 August. In copulation the male stands over the female, 

 his ventral surface opposed to her dorsal, their body axes obliquely 

 inclined, his head a little to one side of the anterior end of her abdomen. 

 One palpus is inserted at a time. On 4 August they were observed 

 in copulation at 7.58 P.M. (three minutes previously they were sepa- 

 rate), and he kept his left palpus inserted for two minutes, the left 

 for nearly two minutes again, the same for one minute, then the right 



