=Sheet-Webs.=—The webs which are such familiar—and, by association, unpleasant—objects in unused rooms and outhouses are usually the work of spiders belonging to the Agelenidae and the Dictynidae. To the first belongs the common House-spider, _Tegenaria civilis_, and its larger congener, _T. parietina_. These spiders are not attractive in appearance, and the last-named species especially, with the four-inch span of its outstretched legs, is a formidable object, and a terror to domestic servants. An obscure tradition connecting it with Cardinal Wolsey and Hampton Court has caused it to be known as the Cardinal Spider. An out-door example of the Agelenidae is the very abundant _Agelena labyrinthica_, whose sheet-web, with its tubular retreat, is to be sought on the banks of ditches, or in the hedges of our country lanes. The snares of these spiders are exceedingly closely woven of very fine silk, and take a long time to complete. The process of their construction may be watched by keeping an _Agelena labyrinthica_ confined in a box with a glass front, and the web, kept free from dust, is a beautiful object, as its fine texture gradually becomes visible as a delicate transparent film which develops by imperceptible stages into an opaque white sheet. The excessive fineness of the silk makes it difficult at first to see what is taking place. The animal is seen to be busily moving about, but the result of its labours only gradually becomes visible. A few delicate foundation-lines are first stretched across the compartment in which it is confined, and upon these the spider walks to and fro incessantly with a serpentine motion, and by and by a muslin-like floor of silk comes into view. An examination of the spinnerets throws some light upon the operation. The posterior pair are very long and mobile, and the hair-like spinning-tubes are distributed on their under surface. The cephalothorax and abdomen are far more rigidly connected in _Agelena_ than in the Orb-weavers, but its length of leg and the length and mobility of its posterior spinnerets enable it to give a wide lateral sweep as it walks along, strewing fine silken threads upon the foundation-lines already laid down. Some hours elapse before even a moderately stout web is constructed, and for long afterwards the spider devotes odd moments of leisure in going over the ground again and strewing new silk upon the gradually thickening web. At one corner a silken tube of similar structure is formed, and in this the spider awaits the advent of any insect which may alight upon the sheet, when it immediately rushes forth and seizes it.