When I procured them they were quite blackened with London smoke, and, on account of their resistance to water, washing them was a very long and troublesome business.
Above the nest are two patches of the Booschmannees-grass, as they appear when laid by the bird.
Below the nest is a group of the eggs of the Gold-tailed Moth, whose nest has already been described. Perhaps the reader wonders where the eggs are. Owing to the mode in which they are arranged, only a few can be seen, and are represented by the little white spots in the lower part of the figure. When the Gold-tailed Moth is ready for the great business of laying her eggs, she seeks a suitable place, and then piles them up in the form of a shallow cone. Her task, however, is not yet finished. Having arranged her eggs, she scrapes off the long downy hairs of the tail-tuft, and arranges them carefully on the eggs so as to cover them with a conical thatch, very much resembling that of an ordinary corn-rick.
The Brown-tailed Moth acts in a similar fashion.
Furs of various kinds act in the same manner, being impervious to wet during the life of the animal. Such, for example, is the fur of the Beaver, that of the Capybara, and that of the Seal, which are animals living in our time. These, however, are exceeded in their thatch-like powers by the three successive coatings of hair that were worn by the ancient Mammoth, the outermost being very long and very coarse, and hanging down in heavy tufts so as to shoot the water from them.
Being on the subject of roofs, we will take a few more examples of the roof as anticipated in Nature.
That parallel fibres, whether animal or vegetable, can throw off rain when properly arranged, has already been shown. Much more is it evident that flat or partly flat plates will have the same effect, if they be arranged so that the joints are “broken,” as masons and bricklayers say, i.e. so that the broad part of the upper row of plates overlaps the junction of two of the plates in the row immediately below it.
On the right hand of the accompanying illustration are given two sketches of a modern roof, one slated and the other tiled. The figures on the left show that this formation has been anticipated by Nature, in the wonderful system of scales which cover the wings of butterflies and moths, and to which all their brilliancy of colour is owing. In spite of their minute size, most being too small to be distinguished by the unaided eye, they are arranged as regularly as the best workman could lay the slates or tiles on a roof, and on exactly the same principle.
The shapes of these scales vary in almost every species, but they are always arranged on the same plan, namely, being placed in successive rows, each overlapping the other.