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The eggs becoming mature, the latter proceeds to make a little web and lays them in it, practising the utmost care. She now covers them over with silk, which she weaves into a cocoon, where the young remain some time after they are hatched. Seldom is the laying seen, for it generally happens in the night-time, or in retired places. Often, in confinement, the spider refuses to lay at all. An egg of a spider, like that of any other animal, is a cell which separates from the body of the female, and subsequently unites with one or more cells that have separated from the body of the male. This process of union, termed fertilization, doubtless takes place when the eggs have attained their full size and are about to be laid. After being laid and hardened it is a very easy matter to watch their development. All that is necessary to be done is to cover the egg to be examined with oil, alcohol or any liquid that will wet it, for this tends to make the shell transparent. Eggs laid in summer are ready to hatch in a fortnight, while those laid in autumn develop slowly all through the winter. A day or two are occupied in hatching. When the time has arrived the shell, or more properly the skin, cracks along the lines between the legs, and comes off in rags, and the spider slowly stretches itself and creeps about. Pale and soft it appears, and devoid of hairs or spines, but its feet are armed with small claws. In two or three days it gets rid of another skin, and begins to assume a spider-like appearance, the eyes becoming dark-colored, the thoracic marks growing more distinct, and a dark stripe appearing across the edge of each segment of the abdomen. The hairs are now long, but few in number, and arranged in rows across the abdomen and along the middle of the thorax. Before the next moult they usually forsake the cocoon, and live together for a short time in a web spun in common. Where larger broods of young spiders live together, they soon show cannibal-like qualities, and if kept in confinement one or two out of a cocoon-full may be raised without recourse to any other food.