THE SPIDERS OF EPPING FOREST.
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upon the under side of which the spider clings in an inverted position. The
ensnaring capabilities of this sheet are often greatly increased by the presence
of numerous fine threads crossing and recrossing some distance above it, and
intended to trip up any unlucky insect which happens to fly against them.
Many argiopiform spiders spin orbicular snares, the "garden spider" (Aranea
diademata, Clk.) being a familiar example.
Eight argiopiform families are represented in this country,
namely, Pachygnathidae, Tetragnathidae, Argiopidae, Ulobori-
dae, Mimetidae, Theridiidae, Pholcidae and Linyphiidae.
This arrangement may be summarised for British species
as follows:—
ORDER ARANEAE.
Sub-order MESOTHELAE (no British representative).
Sub-order OPISTHOTHELAE.
Section I. Mygalomorphae.
Family Atypidae.
Section II. Araneomorphae.
Series I. Dysderiformae.
Family Dysderidae.
Oonopidae.
Scytodidae.
Series II. Drassiformae.
Family Drassidae Family Hahnidae
,, Clubionidae ,, Argyronetidae
Anyphaenidae Dictynidae
Sparassidae Eresidae
Philodromidae Pisauridae
Thomisidae Lycosidae
Salticidae Oxyopidae
Agelenidae
Series III. Argiopiformae. 
Family Pachygnathidae Family Mimetidae
,, Tetragnathidae ,, Theridiidae
Argiopidae Pholcidae
Uloboridae Linyphiidae
It will be noticed that many of the primary divisions of the
order are founded upon characters which, although systematically
of paramount importance, are very obscure and, in some cases,
confined to one sex. The differentiation of the spiracular
systems, for example, would be certain to utterly confuse the
beginner, necessitating as it does the most delicate methods of