This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
The truffle is a subterranean vegetable of the order of Thecaphore. It is an expensive luxury, and is used to add flavour in cooking and as an ingredient of rich meat sauces, pates, etc. It contains no sugar. Eaten in quantity by itself it is a highly indigestible substance. It easily decomposes with a very offensive nauseous odour. There are several varieties, of which the black is the chief, and it is obtained from beneath the trees of oak forests of Perigord in Southern France, where it is hunted by trained Spanish poodles or sows, whose sense of smell enables them to detect the fungus beneath the ground. There is a special hereditary race of truffling swine, broken for the purpose.
The morel is a friable, greyish-black, cone-shaped mushroom, which grows extensively in a variety of dry soils, but, like the cèpe, is obtained principally in France. It may be cultivated artificially. It is used for flavouring, like the truffle.
Cepe is a name given to several mushrooms belonging to the Boletus family, which are globular in shape, and coloured orange or white.