Pliny the Elder [1st century CE] (Natural History, Book 11, 25-27): [Book 11, 25] Among these is a fourth genus, the silk-moth, which occurs in Assyria; it is larger than the kinds mentioned above. Silk-moths make their nests of mud like a sort of salt; they are attached to a stone, and are so hard that they can scarcely be pierced with javelins. In these nests they make combs on a larger scale than bees do, and then produce a bigger grub. [Book 11, 26] These creatures are also produced in another. A specially large grub changes into a caterpillar with two projecting horns of a peculiar kind, and then into what is called a cocoon, and this turns into a chrysalis and this in six months into a silk-moth. They weave webs like spiders, producing a luxurious material for women's dresses, called silk. The process of unraveling these and weaving the thread again was first invented in Cos by a woman named Pamphile, daughter of Plateas, who has the undeniable distinction of having devised a plan to reduce women's clothing to nakedness. [Book 11, 27] Silk-moths are also reported to be born in the island of Cos, where vapor out of the ground creates life in the blossom of the cypress, terebinth, ash and oak that has been stripped off by rain. First however, it is said, small butterflies are produced that are bare of down, and then as they cannot endure the cold they grow shaggy tufts of hair and equip themselves with thick jackets against winter, scraping together the down of leaves with the roughness of their feet; this is compressed by them into fleeces and worked over by carding with their claws, and then drawn out into woof-threads, and thinned out as if with a comb, and afterwards taken hold of and wrapped round their body in a coiled nest. Then (they say) they are taken away by a man, put in earthenware vessels and reared with warmth and a diet of bran, and so a peculiar kind of feathers sprout out, clad with which they are sent out to other tasks; but tufts of wool plucked off are softened with moisture and then thinned out into threads with a rush spindle. Nor have even men been ashamed to make use of these dresses, because of their lightness in summer: so far have our habits departed from wearing a leather cuirass that even a robe is considered a burden! All the same we so far leave the Assyrian silk-moth to women. - [Rackham translation]

Isidore of Seville [7th century CE] (Etymologies, Book 12, 5:8): Silkworms [bombyx] are leaf vermin. Silk cloth [] is prepared from their web. They are called by this name because they are emptied out when they spin their thread, and air alone remains inside them. - [Barney, Lewis, et. al. translation]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Worms 9.9; 9.27): [Thomas describes the silkworm under the names bombax and lanificus.] [Worms 9.9] Bombax [silkworm, silk-moth], as Pliny says, is a worm originating in Assyria. This worm forms a mud nest of such hardness that it cannot be pierced with spikes. In these they make wax combs more abundantly than bees do, and from theses finally a larger worm is produced. It weaves webs like the spider, used for women's clothing and luxury, which is called silk. Weave for yourself, O soul, a disciplined arrangement of body and soul, according to Isaiah, so that, according to Isaiah, Christ may be clothed in his people like an ornament, and it will be as is said to you in the Canticles: How beautiful are your steps in the sandals of the prince's daughter [Christ]. [Worms 9.27] The spinner [lanificus] is a long, spotted worm with many feet; it is sparsely white in color. These worms work silky wool from their own entrails. They use for food the leaves of the mulberry tree, which as food is turned into silken wool by means of the entrails. And they make spindles of their wool in the branches, and work round them, so that they are enclosed in perfect spindles on every side by their work. After this they make their exit at the top of the spindles, and when they come out, they appear to be miraculously changed from their original form, so much so that the worms that before crawled on countless feet now have wings fit for flight. They mate after three days. When this is done the male dies. The female, however, lays innumerable eggs in order, on a substrate of either white or red cloth; then she dies. Then the cloth with the eggs is taken up and stored in a place where the cold of the winter cannot reach the eggs. But after the winter, when the spring season is invigorated by the heat, the stored eggs are placed in the sun and warmed by the heat, until they are formed into worms. There are only two colors of wool on the worm: white and yellow. Others, however, are made by artifice; but nature forms these two only in the worm. It is said, however, that the eggs derive their white or yellow color from the color of the cloth on which they were laid. - [Badke translation/paraphrase]

Bartholomaeus Anglicus [13th century CE] (Liber de proprietatibus rerum, Book18.18): Bombax is a worme that bréedeth in twigges and branches of Cipresse, of Ashe, of Malberrie trées, and of Terebintus, as Plin. sayth lib. 11. cap. 24. And Isid.. saith in this manner, Bombax is a Worme of two twigges and branches: of his weaving is cloathing made, and is called Bombacinium. And is called Bombax, for he is made voyde & cleane while the thred passeth out of him, and in him abideth but aire onely as he sayeth. And this Worme hath wonderfull chaunging: for first he commeth foorth as a worme lyke a Malshrag, that gnaweth caule leaves and vine leaves, this worme may not away with colde, and weaveth webs, as spinners doe: and first he maketh him a place or a house to dwell in, and to defond himselfe against the colde, winter, and maketh his webbe with his feete, and draweth his small threds, and kemeth them with his feet, and ordayneth them so, & maketh therof a webbe. - [Batman]