Accidents arising from the deadly fungi being mistaken for eatable mushrooms are common on the continent, and especially in France. They are not uncommon, too, in Britain; but they are less frequent than abroad, because the epicure’s catalogue of mushrooms in this country contains only three species, whose characters are too distinct to be mistaken by a person of ordinary skill; while abroad a great variety of them have found their way to the table, many of which are not only liable to be confounded with poisonous species, but are even also themselves of doubtful quality.
The present subject cannot be thoroughly studied without a knowledge of the appearance and characters of all the fungi which have been ascertained to be esculent, as well as of those which are known to be deleterious. This information, however, I cannot pretend to communicate, as it would lead to great details. In what follows, therefore, a simple list will be given of the two classes, with references to the proper source for minute descriptions of them, and some general observations on the effects of the poisonous species.
List of the wholesome and poisonous Fungi.—The only good account yet published of the innocent or eatable fungi of Great Britain is contained in an elaborate essay on the subject by Dr. Greville of this place. He enumerates no fewer than twenty-six different species, which grow abundantly in our woods and fields, and which, although most of them utterly neglected in this country, are all considered abroad to be eatable, and many of them delicate. They are the following: Tuber cibarium, or common truffle; T. moschatum and T. album, two species of analogous qualities; Amanita cæsarea or aurantiaca, the Oronge of the French, a species which is often confounded by the ignorant with a very poisonous one, the A. muscaria, or pseudo-aurantiaca; Agaricus procerus; A. campestris, the common mushroom of meadows; A. edulis, or white caps; A. oreades, or Scotch bonnets; A. odorus; A. uburneus; A. ulmarius; A. ostreatus; A. violaceus; A. deliciosus; A. piperatus; and A. acris; Boletus edulis; and B. scaber; Fistulina hepatica; Hydnum repandum; Morchella esculenta, the common morelle; Helvella mitra, and H. leucophæa. Of these the Agaricus acris, procerus, and piperatus are probably unwholesome; and the Amanita cæsarea is very rare in this country, if indeed it is indigenous at all. The A. muscaria, with which it is apt to be confounded, is common enough. The species to which our cooks confine their attention are the Tuber cibarium or truffle, the Agaricus campestris, or common mushroom, and the Morchella esculenta, or morelle. The Agaricus edulis is also to be met with in some markets, but is not in general use.[[2402]]
The best description of the poisonous species is to be found in Orfila’s Toxicology. He enumerates the Amanita muscaria, alba, citrina, and viridis; the Hypophyllum maculatum, albocitrinum, tricuspidatum, sanguineum, crux-melitense, pudibundum and pellitum; the Agaricus necator, acris, piperatus, pyrogalus, stypticus, annularis, and urens.[[2403]] To these may be added the Agaricus semiglobatus, on the authority of Messrs. Brande and Sowerby,[[2404]] the A. campanulatus,[[2405]] the A. procerus, on the authority of a case by Dr. Peddie of this city,[[2406]] the A. myomica, on the authority of Ghiglini,[[2407]] the A. panterinus on that of Dr. Paolini of Bologna,[[2408]] the A. bulbosus of Bulliard, or Amanita venenata, on that of Pouchet,[[2409]] the Agaricus vernus, insidiosus, globocephalus, sanguineus, torminosus and rimosus, on that of Letellier,[[2410]] and the Hypophyllum niveum on the authority of Paulet.
Circumstances which modify their qualities.—The qualities of the fungi as articles of food are liable to considerable variety. Some, which are in general eaten in safety, occasionally become hurtful; and some of the poisonous kinds may under certain circumstances become inert, or even esculent. But the causes which regulate these variations are not well ascertained.
It has been thought by some that most fungi become safe when they have been dried;[[2411]] and there may be some truth in this remark, as their poisonous qualities appear to depend in part on a volatile principle. But it is by no means universally true. Foderé mentions that the Agaricus piperatus continues acrid after having been dried.[[2412]]
Climate certainly alters their properties. The Agaricus piperatus is eaten in Prussia and Russia;[[2413]] but is poisonous in France. The Agaricus acris and A. necator, also enumerated above as meriting their names, are used freely in Russia.[[2414]] The Amanita muscaria in France and Britain is a violent poison, and is considered so even in Russia;[[2415]] but in Kamschatka it yields a beverage which is used as a substitute for intoxicating liquors.[[2416]]
There is some reason to believe also that the weather or period of the season influences some of the esculent species. Thus Foderé has mentioned instances of the common morelle having appeared injurious after long-continued rain.[[2417]]
Even the Agaricus campestris or common mushroom is generally believed to become somewhat unsafe towards the close of the season, or as it turns old. Its external characters at that time are sensibly altered; the margin of the cap is more acute, its white colour less lively, and the fleshy hue of its lamellæ is changed to brown or black. In this state, however, I have often eaten it freely and with impunity.
Cooking produces some difference on their effects. The very best of them are indigestible when raw; and some of the poisonous species may lose in part their deleterious qualities when cooked, because heat expels the volatile principle; but, on the whole, I believe the effect of cooking has not been satisfactorily shown to be considerable. Dr. Pouchet of Rouen seems to have clearly proved, that the poisonous properties of two of the most deadly fungi, the Amanita muscaria and A. venenata, may be entirely removed by boiling them in water. A quart of water, in which five plants had been boiled for fifteen minutes, killed a dog in eight hours, and again another in a day; but the boiled fungi themselves had no effect at all on two other dogs; and a third, which had been fed for two months on little else than boiled amanitas, not only sustained no harm, but actually got fat on this fare.[[2418]] Pouchet is inclined to think that the whole poisonous plants of the family are similarly circumstanced.—On the other hand some cryptogamous botanists have maintained that the qualities of the esculent mushrooms are injured by cooking, and that when used in the raw state they may be taken for a long time as a principal article of food without injury. This statement, as to the effect of mushrooms when used for a length of time as food, will be more fully considered presently. It is easy to understand how boiling may remove their active properties, although other modes of cookery may not do so. Roasting had no effect in impairing the activity of Agaricus procerus in the case observed by Dr. Peddie.