1909.] NATURAL SCIENCES OF PHILADELPHIA. 563 



female to fight the other male, and this fighting of the two males upon 

 and around her body continued for half an hour, when I separated 

 them. The next day the same fight was renewed over her motionless 

 body for 50 minutes, when the female rose and walked away, the 

 males, thereafter, avoiding her. The copulatory attitude Is like that 

 of X. stomachosus, previously described by me (1903). The males 

 appeared as eager to fight as to mate. 



Caratinopsis interpres Em. 



Two males and a female of this small theridiid were placed in a vial 

 on 12 July. The males were savage on meeting and grappled with 

 each other. Within a few minutes the three had spun a maze of lines. 

 Twice it happened that both males simultaneously seized and tried 

 to embrace the female, and once one male copulated while the other 

 endeavored to do so; in each case the female shook both off at the 

 end of a minute or two. Finally one male inserted both palpi con- 

 tinuously for 21 minutes; their heads were in the same direction and 

 ventral surfaces apposed, the male held her with his first two pairs of 

 legs and had his head a little posterior to her epigynum. 



7. Nesting and Cocooning. 



The architectural habits of Ariadna and Pisaurina have been 

 described above. 



Phidippus purpuratus K. 



We have mentioned that during June a male and female are fre- 

 quently found together in one nest, and such mating nests are well 

 known for the Attids; these are perhaps the same as the nests which 

 the females occupy during the Winter. But on bringing home such 

 pairs and placing them in cages no such mating nests were made, but 

 the male and the female each built a thin-walled nest with two aper- 

 tures, during which they remain mostly only at night; the two would 

 also use the nests interchangeably, and would usually copulate outside 

 of them. Before cocooning each of my captive females spun in 

 an angle of the cage a much larger, entirely closed nest, so thick-walled 

 that she can scarcely be seen through it, and within this spun all the 

 cocoons of one season. Whether under natural conditions, on the 

 lower side of a stone, the female would employ her mating-nest as a 

 cocoon-nest, or whether the two are separate structures, I have not 

 ascertained. The male may enter the cocoon-nest after the female 

 has made an opening to it, to copulate with her, but he never remains 

 long therein, but usually spins a smaller nest of his own on its outer 



