FIELD BOOK OF INSECTS. 



The large, hairy, much-feared tarantulas live in the 

 South and some of them build interesting trap-door nests. 

 The following families are true spiders. The DICTYNID.E 

 belong to a group having special attachments on their 

 spinning machine by which they make hackled bands in 

 their webs; most of the tangled, sheet webs on the sides of 

 houses, especially at windows, are made by Dictyna sub- 

 /a/a. The THERIDIID^: have a well developed comb on 

 the hind legs to aid in throwing liquid silk over the prey 

 they wish to entangle; Theridion tepidariorum is the 

 house spider, the one which makes the tangled web in the 

 corners of rooms where "no beaux will go." Latrodectus 

 mactans, a jet-black spider marked with red or yellow, 

 living under stones or pieces of wood, also belongs to this 

 family and is the only spider of northeastern United 

 States concerning which there is even moderate evidence 

 of its seriously biting human beings. 



The ARGIOPID.E are the orb weavers, par excellence. 

 They usually have relatively large abdomens. The 

 maker and the making of a fairly typical web are shown 

 in Plate VI, which is based upon an exhibit in the Ameri- 

 can Museum of Natural History. This spider is very 

 common about buildings and has had a variety of names 

 of which Aranea sericata is believed to be better usage 

 than the more commonly employed Epeira sdopetaria. 

 She started above a on a beam or twig and dropped, 

 spinning a thread as she went, to another support below 

 b, fastening the thread there. She then climbed this 

 thread to the upper support, crossed over to a point above 

 c and dropped to a point below d, making a strand as 

 before. Then, going to e, she fastened one end of a strand 

 and, spinning it behind her, went across by way of the 

 upper support to /. She then went to the upper support 

 and dropped to this e-f strand, fastening the new line at 

 h; this pulled e-f up slightly. The next strand which she 

 put in was from i to a point on the lower support below j; 

 pulling this line made another angle in e-f, as did the 

 following one from k to b. These last two strands were 

 fastened near their center by a bit of silk and the remain- 

 ing radii were put in by moving about on the foundation 

 of the web. The next step in the operation was a laying 



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