Truffles (_Tuber cibarium_) may receive a passing notice whilst treating of fungi, though they are really subterranean tubers of an edible sort found in the earth, especially beneath beech trees, and uprooted by dogs trained for the purpose. They somewhat resemble our English "earth nuts," which swine discover by their scent. The ancients called the Truffle _lycoperdon_, because supposing it to spring from the dung of wolves. In Athens the children of Cherips had the rights of citizenship granted them because their father had invented a choice ragout concocted of Truffles. But delicate and weak stomachs find them difficult to digest. Pliny said, "Those kinds which remain hard after cooking are injurious; whilst others, naturally harmful if they admit of being cooked thoroughly well, and if eaten with saltpetre, or, still better, dressed with meat, or with pear stalks, are safe and innocent." In Italy these tubers are fried in oil and dusted with pepper. For epicures they are mixed with the liver of fattened geese in _pate de foie gras_. Also, greedy swine are taught to discover and root them out, "being of a chestnut colour and heavy rank hercline smell, and found not seldom in England." Black Truffles are chiefly used: but there are also red and white varieties, the best tubers being light of weight in proportion to their size, with an agreeable odour, and elastic to the touch. They are stimulating and heating, insomuch, that for delicate children who are atrophied, and require a _multum in parvo_ of fatty and nitrogenous food in a compact but light form, which is fairly easy of digestion, [372] the _pate de foie gras_ on bread is a capital prescription. Truffles grow in clusters several inches below the soil, being found commonly on the downs of Wiltshire, Hampshire and Kent; also in oak and chestnut forests. Dogs have been trained to discriminate their scent below the surface of the soil, and to assist in digging them out. There is a Garlic Truffle of a small inferior sort which is put into stews; and the best Truffles are frequently found full of perforations. The presence of the tubers beneath the ground is denoted by the appearance above of a beautiful little fly having a violet colour--this insect being never seen except in the neighbourhood of Truffles. They are subject to the depredations of certain animalcules, which excavate the tubers so that they soon become riddled with worms. These, after passing through a chrysalis state, develop into the violet flies. Gerard called Truffles "Spanish fussebals." They were not known to English epicures in Queen Elizabeth's day. Another appellation borne by them formerly was "Swines' bread," and they were supposed to be engendered by thunderbolts. In Northern France they were first popularised four hundred and fifty years ago, by John, Duke of Berry, a reprobate gambler, third son of John the Good. The Perigord Truffle has a dark skin, and smells of violets. Piedmontese