ON ARACHNIDA. 
473 
fights to the death. It has been observed, that where this 
theridion is most common, a hymenopterous insect, known by 
the trivial name of Si. John's Jly, in all probability a spliex, 
or pompilus, destroys a great number of them. The cocoon 
is about the size of a hazel-nut, and the mother guards it with 
the greatest assiduity. 
Degeei has observed another Theridion ( aranea bipunc- 
tuata of Linnaeus) spin round the insect arrested in its snare, 
as well as all round the neighbourhood, fresh threads, drawing 
them with its hinder feet, so as to hinder its prey from break- 
ing its fetters, and then attack it with open force, kill it, and 
drag it within its domicile ; this is usually in the cleft of a 
casement. The angles, the corners of the walls which are 
near it, are curtained with its web, which is loose and 
spreading. 
The species of the genus Linyphia, the most common 
( triangularis) spins on bushes, &c., particularly towards the 
end of summer, a horizontal web, hung between the branches, 
slender, not compact, and the extent of which, often consider- 
able, varies in proportion to its proximity to, or distance from, 
the points of attachment. To maintain it in the same situa- 
tion, and prevent its sinking, it spreads above and on all sides, 
perpendicular and oblique threads, which it fixes to the 
branches in the neighbourhood. They are sometimes even so 
drawn that the web becomes convex. It is suspended in the 
midst of this very irregular assemblage of threads, being 
directed and crossing on all sides. The animal remains in an 
inverted position, having the belly upwards and usually at 
the centre of the web ; as soon as an insect is caught there, 
it runs out quickly, pierces it with its mandibles through the 
web, makes a rent there to allow it to pass, and without 
enveloping it with silk, sucks the insect which is dead, or 
excessively enfeebled by the effects of the poison. When 
many individuals of this species are placed together, they 
