228 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



the window and other parts of the room, marking points where little ad- 

 venturers, following their inherent tendency, had departed from their 

 " Eiffel Tower " of spinning threads, and dispersed into other parts of the 

 building. 



VIII. 



A valuable account of life within the cocoon of a mother Argiope is 

 given by Frederick Pollock, Esq. 1 The cocoon, which resembles substan- 

 tially that of Argiope argyraspis, contained from six hundred to 

 Argiope one thousand bright yellow eggs glued together in the shape of 



ia " a bean. The egg shells burst at the end of the fourth week. 

 Cocoon 

 Life 1^ ie spiders at that time were helpless and nearly transparent. 



At the end of the fifth week they cast off their first skin and 

 became quite lively and active. Their color at this time was a bright 

 yellow, with darkish legs. Their bodies were about the size of an ordi- 

 nary pin head. Three or four dark spots gradually developed down each 

 side of the abdomen. At about the end of the seventh week the spider- 

 lings emerged through a small hole probably gnawed by them. 



After departure from their cocoon their habits, as reported by Mr. Pol- 

 lock, agree with those of young Epeiroids as heretofore described. They 

 club harmoniously together, hanging closely packed in a ball, upheld by 

 numerous lines attached to adjacent objects. This community life con- 

 tinues for ten days or a fortnight, the spiders occasionally separating them- 

 selves from their snugged or balled estate, but always reverting to it. Dur- 

 ing this time they eat nothing. 



At the close of a fortnight this friendly condition ceases. The indi- 

 viduals of the brood scatter abroad, and each individual makes a round 



web about the size of a penny. Mr. Pollock conjectures that on 

 w , account of the extreme weakness of these webs few insects are 



held by them, and that in consequence hundreds of spiderlings 

 at this precarious period of their existence perish from starvation or other 

 causes. He thinks that not more than one or two out of the entire brood 



survive. In this estimate of mortality he is doubtless correct as 

 Mortality f ar as cer tain seasons are concerned. A heavy storrn will destroy 



a whole brood. The presence of some skillful enemy wdll work 

 Young a s i m il ar destruction, but under favorable circumstances quite a 



number of the brood will survive. The contingencies, however, 

 are uncertain, and the life of baby spiders during the first few weeks of 

 their existence hangs by an even weaker thread than that which they spin. 

 Their little webs are strong enough to hold microscopic insects, the only 

 kind that spiderlings could prey upon at their time of life. 



1 On the History and Habits of Epcira aurelia. Annals and Magazine of Natural His- 

 tory, page 459. 



