274 MANUAL OF NATURAL HISTORY-. 



I. S UB-ORDER. — Quadripulmonary-Spiders 

 (Tetrapneumona). 



Two pulmonary sacs and two spiracles on each 

 side ; legs robust. 



1. Family. — Bird-Spiders (Mygalidse). Eyes eight ; 



spinnerets four, two short and two promi- 

 nent ; hook or moveable claw of chelicerse 

 folded on the lower side, or that of the first 

 joint, moving vertically. 



2. Family. — Hunting-Spiders (Dysderidae). Eyes 



six in many ; spinnerets six, very short ; 

 hook of chelicerse folded transversely or 

 along their inner side, moving laterally. 



II. S UB-ORDER.— Bifvimoxaiiy-Sfivers 

 (Dipneumona). 



A single pulmonary sac and spiracle on each side 

 of abdomen. 



8. Family — True -Spiders (Araneidse). Hook of 

 chelicerae folded transversely or along their 

 inner side, moving laterally. 

 L Group. — Sedentary Spiders (Sedentaria). Eyes 

 arranged transversely on front of cephalo- 

 thorax ; throw out threads for the capture 

 of their prey, and station themselves upon 

 or near their webs. 

 1. — Tapestry - Weavers (Clubioninae). Spin- 

 nerets cylindrical, placed together and 

 directed backwards; legs robust; recti- 

 grade. 



