OCR Text |
Show 1870.] MR. HUDSON ON THE BIRDS OF BUENOS AYRES. 547 to contain a large proportion of coleopterous insects. I think it very probable that the vast unexplored regions lying between the grassy pampas and the Andes will be found to be the native country of these birds. I haver never met here with any specimens of the Teenioptera nengeta. " To see the webs of the Gossamer-Spiders floating in the air is here an exceedingly common thing. These little aeronauts are so numerous that on any still day in warm weather, if one sits down on the grass, he will observe numbers of them briskly moving about, while some, running to the point of a blade or leaf, suddenly dart out their invisible lines and float off. I recollect once, several years ago, the sky was for several days full of white masses composed of these floating webs. But this afternoon, while I was out shooting, these Spiders and their webs presented an appearance that was altogether new to me. Walking along a stream I observed skirting the edge of the low wet ground on the opposite side a broad white line. This I discovered to be caused by the quantities of gossamer that almost completely veiled the grass and thistles under it. This zone of gossamer was about twenty yards wide; and outside of it only a few scattered webs were visible. I did not ascertain its length, but followed it ahout two miles without finding its end. I enclose a small strip of the webs, which could be easily peeled off every object presenting a smooth surface. I observed many of the Spiders; indeed so numerous were they that they continually baulked each other in their attempts to rise in the air. There being a breeze blowing, as soon as one threw out his web it would be entangled in that of another. Both Spiders would immediately seem to know the cause of the trouble, for they would run angrily together, each trying to drive the other off. There appeared to be at least three different species of Spider. One of these had a round scarlet body ; another, of a velvet-black, had a square large corslet and small pointed abdomen. But the greatest number were of the third kind; they were all shades of olive colour, from pale green to greenish black, and of various sizes, the largest being in body a quarter of an inch long. These Spiders could not have been brought by the wind, as the zone of webs followed the windings of the stream, but had probably bred in the low ground along its margin and had now gathered on its edge ready to migrate. " 2/th. On the 25th I went to visit the Spiders I have spoken ahout, fully expecting they would be gone, as we have had wind and rain since I first saw them. To m y surprise they were vastly increased in number ; on the tops of cardoons they literally were in heaps. Most of them were large and of the olive-coloured species, and were floating off in great numbers, the day being calm. I noticed another kind, of a pale slate-coloured body elegantly striped with black, and pink legs. On the 26th I went again to see them; and the whole army of Spiders, save a few solitary stragglers, had disappeared. « ye r y trulv y o u r S) " WILLIAM H. HUDSON." |