ig8 THE SPIDERS OF EPPING FOREST. 



19. Tibiae, metatarsi and tarsi of legs I and II with 



a row of long strong spines upon their 

 undersides .. •• •• Mimetidae 



Legs I and II without such spines. . . . 20 



20. Tarsi IV with a double row of short curved 



spines upon their undersides. Remaining 

 joints of legs usually without spines. 

 Tibia of male palpus without apophysis. . Theridiidae 

 Tarsi without spines. Legs almost invariably 

 furnished with spines which, however, 

 are sometimes very minute and confined 

 to tibia IV. In this latter case the tibia of 

 the male palpus is almost always furnished 

 with an apophysis . . • • 21 



21. Height of clypeus greater than length of ocular 



area (except Tapinopa and Tapiiiocyha). 

 Falces without basal protuberances . . Linyphiidae 



Height of clypeus not greater than length of 

 ocular area. Falces often with basal pro- 

 minence .. .. -• Argiopidae 



22. Tube tracheae opening in two apertures close 



behind the laminal tracheae . . . . Argyroiietidae 



Tube tracheae opening in a single aperture 



just in front of the spinners . . . . 23 



23. Spinners normally arranged in a group . . Agelenidae 

 Spinners arranged in a transverse row beneath 



the extremity of the abdomen, the long 

 spinners, corresponding to the superior 

 ones of the Agelenidae, at the end of the 

 row . . . . . . . . Hahnidae 



24. Eyes in four unequal rows. Legs furnished 



with numerous very long spines . . Oxyopidae 



Eyes in three rows of 4, 2, 2, four in the front 



row . . . . . . . . 25 



25. Eyes of first row very large. Tarsal claws 2 . . Salticidae 

 Eyes of first row small. Tarsal claws 5 . . 26 



26. Second row of eyes much shorter than the third. 



Clypeus high. Tibia of male palpus with 



an apophysis . . . . . . Pisauridae 



Second row of eyes not much shorter than the 

 third. Clypeus moderate. Tibia of male 

 palpus without an apophysis . . . . Lycosidae 



Note. — Pholcomma gibbum , a very minute Theridiid, has the eyes arranged 

 as in Pholcidae. The caput of the male in some cases is elevated and the 

 position of the eyes modified in consequence. Such species may be referred 

 to the family Linyphiidae or more rarely to the family Theridiidae. 



