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Show 40 RIO DE .TANEIRO. May-June, 1832. When the ants came to the road they changed _their course, and in narrow files reascended the wall. H_avmg placed a small stone, so as to intercept one of the h~es, the whole body attacked it, and then immediately retued. Short~y afterwards another body came to the charge, and agam having failed to make any imp_ression,_ this line of march was entirely given up. By gomg ~n mch round, the file might have avoided the stone, and this doubtless wo~ld have happened, if it had been o~iginally ~here : but havm? been attacked, the lion-hearted httle warnors scorned the Idea of yielding. . . Certain wasp-like insects, whwh construct m the corners of the verandahs clay cells for their larvre, are very numerous in the neighbourhood of Rio. 'rhese cells they stuff full of dead and dying spiders and caterpillars. I was much interested one day by watching a deadly contest between a Pepsis and a large spider of the genus Lycosa. The wasp made a sudden dash at its prey, and then flew away: ' the spider was evidently wounded, for trying to escape, it rolled down a little slope, but had still strength sufficient to crawl into a thick tuft of grass. The wasp soon returned, and seemed surprised at not immediately finding its victim. It then commenced as regular a hunt, a!'l ever hound did after fox ; making short semicircular casts, and all the time rapidly vibrating its wings and antennre. The spider, though well concealed, was soon discovered; and the wasp, evidently still afraid of its adversary's jaws, after much manreuvring, inflicted two stings on the under side of its thorax. At last, carefully examining with its antennre the now motionless spider, it proceeded to drag away the body. But I stopped both tyrant and prey.* The number of spiders in proportion to other insects, is ~ Don Felix Azara, vol. i., p. 17 5, mentioning a hymenopterous insect, probably of the same genus, says, he saw it dragging a dead spider through tall grass, in a straight line to its nest, which was one hundred and sixty-three paces distant. He adds that the wasp, in order to find the road, every now and then made "rlemi-tours d'environ trois palmes." May-June, 1832. ARACIINID.IE. 41 here as compare~ to England very much increased; perhapsmore so, than With any other division of the articulate ani~ als .. The variety of species among the saltigrade, or.jumpmg _spiders, ap_pear~ almost infinite. The genus, or rather family of Epeira, . IS here characterized by many singular forms; some species have pointed coriaceous shells, others enlarged and spiny tibire. Every path in the forest is barricaded wit~ t_h~ stro~g yellow web of a species, belonging to _the same divisiOn With the Epeira clavipes of Fabricius, whi?h was formerly said by Sloane to make, in the West Indies, webs so strong as to catch birds. A small and pretty kind of spider, with very long anterior legs, and which appears to belong to an undescribed genus, lives as a para~ It~ o~ almost every one of these webs. I suppose it is too ms1gmficant to be noticed by the great Epeira, and is therefore all~wed to prey on the minute insects, which adhering to. th~ hnes, .would otherwise be wasted. When frightened, this httle spider either feigns death by extending its front legs, o~ ~u.ddenl! drops from the web. A large Epeira of the same ~VISIOn With Epeira tuberculata and conica (with fleshy P_romi~ences ?n i~s abdomen) is extremely common, espeCially m dry s~tuatiOns. Its web, which is generally placed among the great leaves of the common agave, is sometimes s~rengthened_ near the centre by a pair or even four zigzag nbbo~s, whiCh connect two adjoining rays. When any large ~nsect, _a~ a grasshopper or wasp, is caught, the spider, ~y qmc~y _givmg it a revolving movement, and at the same time emi~tmg a ~and of threads from its spinners, soon envelops Its prey m a case like the cocoon of a silkworm The spider now examines the powerless victim and give~ ~he f~tal bite on the hinder part of its thorax ; then retreat~~ g, It patiently waits till the poison has taken effect. The VIrule~ce of this poison may be judged of, from the fact that m half a minute I opened the mesh, and found a large wasp quite lifeless. This Epeira always stands with its head downwards near the centre of the web. When disturbed, it acts differently according to circumstances: if |