At Caldera, Mr. Adams observed a dingy little species of spider of the genus Clubiona, concealing itself in very snug retreats formed out of a dead leaf, rolled round in the shape of a cylinder, lined with a soft silken tissue, and closed at one end by means of a strong woven bolt-door. When hunted, it was amusing to see the frightened little creatures run for protection into their tiny castles, where they would doubtless be safe from the attacks of birds, owing to the leaves not being distinguishable from others that strew the ground. All species of spiders are gifted with an admirable maternal instinct, and resort to various methods for the purpose of securing their cocoons. The Theridion, when a seizure of the precious burden is threatened, tumbles together with it to the ground, and remains motionless, while the Thorinsa covers it with its body, and when robbed of it, wanders about disconsolate. In a forest of the Sooloo Islands, Mr. Adams found the ground literally overrun with a small black agile species of Lycosa, many of which had a white flattened globose cocoon affixed to the end of their abdomen. It was most amusing to watch the care with which these jealous mothers protected the cradles of their little ones, allowing themselves to fall into the hands of the enemy rather than be robbed of the silken nests that contained them. If the spiders are at war with all other insects, and contribute to keep them within bounds by the destruction they cause among their ranks, they in their turn are sorely persecuted creatures. Monkeys, squirrels, lizards, tortoises, frogs, and toads catch and devour them wherever they can. In Java and Sumatra, we even find a family of sparrows named _Arachnotheræ_, from their living almost exclusively on spiders. Armed with a prodigiously long recurved and slender beak, these birds know how to pursue them and drag them forth from the most obscure recesses. It is amongst the insects, however, that the spiders have to fear their most numerous and formidable enemies. Independently of those which they find in their own class, the centipedes seize them beyond the possibility of escape; and several species of wasps, more savage and poisonous than themselves, will rush upon spiders eight times their size and weight, and benumbing them with a sting, bear them off to their nests, to serve as food for their larvæ. Others attack the spiders in their progeny. The _Pimpla Arachnitor_ pierces with its invisible gimlet the tender skin of the spider’s egg, and, without tearing it, introduces its own eggs into the liquid. The pimpla’s egg soon comes to maturity, and the larva devours the substance of that of the spider, from whence a winged insect bursts forth--a phenomenon which made some naturalists, too hasty to judge from appearances, believe that spiders were able to procreate four winged flies.