368 ARACHNIDA—ARANEAE CHAP. 
Mimetus interfector, of still more ferocious and piratical habits. 
Its special quarry is Zheridion tepidariorum. Sometimes the 
Theridion overcomes the invader, and one case was observed in 
which a second Jfimetus was devouring a Theridion beside the 
dead body of its predecessor, who had come off the worse in the 
combat. 
The eggs of TZheridion tepidariorum are also sometimes 
devoured by this spider, and a similar propensity has been 
observed in some English species, for Staveley ' states that it is 
common to see certain spiders of the genus Clubiona feeding upon 
the eggs which have been laid by their neighbours. The larvae 
of some Hymenopterous insects are parasitic upon Spiders them- 
selves, and not upon their eggs. Blackwall found this to be the 
case with the larvae of Polysphincta carbonaria, an Ichneumon 
which selects spiders of the genera petra and Linyphia on 
which to deposit its eggs.” The spider thus infested does not 
moult, and is soon destroyed by the parasite which it is unable 
to dislodge from its back. Menge, in his Preussische Spinnen, 
enumerates several cases of parasitism in which the larva, as 
soon as it has developed from the egg, enters the spider’s body, 
there to continue its growth. Spiders are also subject to the 
attack of a parasitic worm, Gordius (cf. vol. 1. p. 173). 
Some of the most deadly foes of Spiders are the Solitary 
Wasps. There are many species of Pompilus (vol. vi. p. 101), 
which, having excavated holes in clay banks, store them with 
spiders or other creatures which they have paralysed by their sting. 
They then deposit an ege in the hole, and immediately seal up the 
orifice. This habit is found to characterise the solitary wasps of all 
parts of the world. Belt * relates the capture of a large Australian 
spider by a wasp. While dragging its victim along, it was much 
annoyed by the persistent presence of two minute flies, which it 
repeatedly left its prey to attempt to drive away. When 
the burrow was reached and the spider dragged into it, the two 
flies took up a position on either side of the entrance, doubtless 
with the intention of descending and laying their own eggs as soon 
as the wasp went away in search of a new victim. Fabre * gives 
an interesting account of one of the largest European Pompilidae, 
| British Spiders, 1861, p. 102. 2 Ann. Nat. Hist. (1), xi., 1843, p. 1. 
3 Naturalist in Nicaragua, 2nd ed., 1888, p. 134. 
* Nouveaux souvenirs entomologiques, ch. xii. 
