370 SYNOPTIC COLLECTION. 



stays and from which the forward part of its body is put 

 out. The web is so close and tight that according to 

 Emerton 1 "one can hear the footsteps of the spider as 

 she runs about on it." 



When the web is finished she waits in the tube until an 

 insect is caught in the snare when she runs out, catches 

 her prey, and retires into the tube to eat it. 



Just as the young Cteniza knows how to construct its 

 trap-door nest, so the young Agalena possesses a knowl- 

 edge of the art of web-making inherited from its ances- 

 tors near and remote. 



Nephila (PI. 915, N. plumipes Koch) differs from the 

 other orb-weavers in having an abdomen much longer 

 than the cephalothorax. In life this spider is brilliantly 

 colored and provided with hairs of a silvery luster. The 

 difference between the sexes, which is generally great, is 

 seen in this genus, the male (fig. 2) being about a tenth 

 as large as the female (fig. i). 



The common spider, Epeira sdopetaria Clerck (=. 

 vulgaris Hentz), (No. 916, 9, $ ; PI. 917, figs, i, 2) car- 

 ries the art of web-making to great perfection. It selects 

 a window-frame, fence, or some other favorable locality 

 and spins a line across the space where the future web is 

 to be. Then it spins radial threads as seen in PI. 918 

 from the center to certain fixed points on the circumfer- 

 ence. When this is done it makes a spiral scaffolding 

 from the center to the outside, then retracing its steps, it 

 spins a closer spiral of adhesive threads (see PI. 918) 

 behind it while it tears down the scaffolding in front of 

 it. On approaching the center it allows the scaffolding 

 of non-adhesive threads to remain, 2 evidently because it 

 is here at the center that the spider stays much of the 

 time. When the prey is caught in the web the spider 



1 The Structure and Habits of Spiders, 1878, p. 55. 



2 Campbell, Trans. Hertfordshire Nat. Hist. Soc., I, part i, 1880, 

 p. 44- 



