Wild hornets live in the holes of trees, and in winter, like other insects, keep themselves concealed; their life does not exceed two years in length. Not unfrequently, their sting is productive of an attack of fever, and there are authors who say that thrice nine stings will suffice to kill a man. In spring they build their nests, generally with four entrances, and here the working hornets are produced: after these have been hatched they form other nests of larger size. These races, too, have their drones. Neither hornets nor wasps have a king, nor do they ever congregate in swarms. CHAPTER VII. THE SILK-WORM. Another class of insects spring from a grub of larger size, with two horns of very peculiar appearance. The larva becomes a caterpillar, after which it assumes the state in which it is known as _bombylis_, then that called _necydalus_, and in six months it becomes a silk-worm. These insects weave webs similar to those of the spider, the material of which is used for making the more costly and luxurious garments of ladies, known as “bombycina.” Pamphile, a woman of Cos, the daughter of Platea, was the first person who discovered the art of unravelling these webs and spinning a tissue therefrom. The silk-worm is said to be a native of the isle of Cos, where the vapors of the earth give new life to the flowers of the cypress, the terebinth, the ash, and the oak which have been beaten down by the showers. At first they assume the appearance of small butterflies with naked bodies, but soon after, being unable to endure the cold, they throw out bristly hairs, and assume quite a thick coat against the winter, rubbing off the down that covers the leaves, by the aid of the roughness of their feet. This they compress into balls by carding it with their claws, and then draw it out and hang it between the branches of the trees, making it fine by combing it out: last of all, they take and roll it round their body, thus forming a nest in which they are enveloped. In this state they are taken; after which they are placed in earthen vessels in a warm place, and fed upon bran. A peculiar sort of down soon shoots forth upon the body, on being clothed with which they are set to work upon another task. The cocoons which they have begun to form are rendered soft and pliable by the aid of water, and are then drawn out into threads by means of a spindle made of a reed. Even men have not felt ashamed to make use of garments formed of this material, in consequence of their extreme lightness in summer: for, so greatly have manners degenerated in our day, that, so far from wearing a cuirass, a thin garment is found to be too heavy. CHAPTER VIII. SPIDERS.