THE HOUSE SPIDER 189 



The writer has settled this question to his own satisfaction. 

 Spiderlings will gnaw their way out without any aid from the 

 female, if for any reason she is not present to help. In support 

 of this statement the following recorded observations are given. 

 A female that had cocooned in captivity was removed from her 

 breeding cage to see if the spiderlings would emerge by them- 

 selves. Nine days later the brood of spiderlings had emerged. 

 The male had died in this case before the female was removed. 

 Again a cocoon which had been spun in a breeding cage was re- 

 moved, and placed by itself in a large bottle. Five days later 

 three spiderlings had emerged. There was so much moisture in 

 this bottle that soon the cocoon was covered with mold. No more 

 spiderlings were observed to emerge, but an exit hole had been 

 made for them. 



In the writer's recorded daily observations on webs in their 

 natural environment several records were made of the emergence 

 of spiderlings from cocoons that were unaccompanied by the 

 adult spider. On June 15, 1910, a brood of spiderlings was ob- 

 served to emerge from a co^coon in a web on which no adult 

 had been observed since June 6 previous. Again on June 29, 

 1910, a brood of spiderlings emerged from a cocoon on a web 

 that had been inhabited for two days previous only by a spider- 

 ling about 3 mm. long. On this same snare on July 7 a second 

 brood of spiderlings emerged from a second cocoon. No adult 

 had been recorded since the emergence of the spiderlings from 

 the first cocoon. On another snare observed in the College 

 G-reenhouse a female spun her first cocoon on either June 5 or 

 June 6. On June 7 the snare was deserted, the cocoon only 

 being left. It remained in this condition until June 23, when 

 the spiderlings emerged by themselves. Several other records 

 were made of spiderlings emerging by themselves, but they will 

 not be quoted here, since enough have been given, it is believed, 

 to establish the fact that they are capable of doing so. 



Cannihali>s))h. — Caimibailism is known to exist amouyg some 

 spiders, as it does among some insects, but it is probable that 

 there has been much exaggeration in many of the reports of can- 

 nibalism among spiders. Again many species may prove to be 

 cannibalistic when kept under unnatural conditions ; especially 

 is this true where they are crowded or are not sufficiently fed. 

 That the first active nymphs that appear inside the cocoon in the 



