Vegetable life also exists in caverns, but consists of such mushrooms or fungi which, shunning the light, love darkness and damp. For their existence, however, moisture and warmth of air is necessary, but they are invariably dependent on organic basis, and are commonly found germinating on pieces of wood, particularly in a state of decomposition. More than seventy subterranean fungi have been discovered, some remarkable for their size. A few years ago a fungus was found growing from the wood-work of a tunnel near Doncaster, which measured no less than fifteen feet in diameter. In the neighbourhood of Paris the cultivation of edible mushrooms is extensively carried on in the catacombs or caverns, seventy or eighty feet below the surface, where the temperature is uniform all the year round. In one of the caves of Mount Rouge there are no less than six or seven miles of mushroom bedding. Among the wonders of the subterranean world must be classed the bone caves of Europe and other parts of the world. In some caves in England, the bones of a prodigious bear have been found, and many hundreds of those of a hyena, considerably larger and more formidable than those existing in Africa. Besides the bear and hyena, upwards of a hundred species of extinct animals have been found in the ossiferous caves of Great Britain, among them being those of the elephant and a rhinoceros. Though in Europe bone caves contain the remains of animals very different from those now existing in the same regions, yet in the caves of Brazil extinct species of nearly all the territorial quadrupeds now inhabiting this region occur. The Australian caverns contain fossil bones of a large extinct kangaroo. In New Zealand the wingless apteryx is still found in the wilds, and the caves of that country show us that it was preceded by other wingless birds of gigantic stature; among them the moa, which, when alive, must have stood about thirteen or fourteen feet high. A complete leg of the bird has been discovered six feet in length, and portions of the eggs show that they had been about 6 or 7 inches diameter. CHAPTER TEN. ARRANGEMENTS OF THE MINES. In Germany mining operations are carried on in the most systematic manner. Miners are dressed as their ancestors were hundreds of years ago, and they cling pertinaciously to their ancient usages. In some workings prayers are offered up, led by the engineer, before the miners descend to their work, while they stand grouped round him at the opening of the mine, a custom which might well be adopted in our own country. The German miner retains also the superstitions of his forefathers, and still believes in the genii of the mines, named Nickel and Kobald, after whom he has called two metals, nickel and cobalt, originally discovered in the mines of Saxony.