CHAPTER VII: 



Superfamily ARGIOPOIDEA (Ar-gi-o-poi'dc-a) 

 The True Spiders 



The superfamily Argiopoidea includes all but two of the 

 thirty families of spiders represented in our fauna, that is all 

 except the tarantulas, which are found only in the South and in 

 the West. 



In this superfamily the chelicerae project downward (ven- 

 trad) or obliquely downward (Fig. 229); the claw of the chelic- 

 erae moves more or less directly toward the middle plane of the 

 body; the pedipalps are furnished with endites (Fig. 230); and 

 except in the first family there is only a single pair of book- 

 lungs or none. 



The sequence and grouping of the families adopted in this 

 work is shown in tabular form on pages 221-222. 



Family HYPOCHILID^E (Hyp-o-chil'i-dae) 



The Four-lunged True Spiders 



In the mountains of eastern Tennessee and of neighbouring 

 states there lives a very remarkable spider, which was first de- 

 scribed by Dr. George Marx ('88), and for which the family 

 Hypochilidae was established (Fig. 231). Two other species 

 belonging to this family have been discovered, one in China, and 

 one in Tasmania. These are undoubtedly True Spiders, that is 

 they belong to the Superfamily Argiopoidea, but they differ from 

 all other members of this superfamily and agree with the 

 Tarantulas, the Avicularioidea, in the possession of two pairs of 

 book-lungs. 



The second pair of book-lungs is situated near the middle 

 of the ventral aspect of the abdomen, and their spiracles are 

 connected by a prominent furrow. There are eight eves, of 

 which the anterior median are dark and the others pearly white; 



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