Page:Treatise on poisons in relation to medical jurisprudence, physiology, and the practice of physic (IA treatiseonpoison00chriuoft).pdf/709

 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.

On certain persons all mushrooms, even the very best of the eatable kinds, act more or less injuriously. They cause vomiting, diarrhœa, and colic. In this respect they are on the same footing with the richer sorts of fish, which by idiosyncrasy act as poisons on particular constitutions. It is probably under this head that we must arrange an extraordinary case mentioned by Sage of a man who died soon after eating a pound of truffles. He was seized with headache, a sense of weight in the stomach, and faintness; and he lived only a few hours.

Lastly, it is not improbable from a singular set of cases to be related presently, that, contrary to what some botanists have alleged, the best mushrooms when taken in large quantity, and for a considerable length of time, are deleterious to every one.

Foderé, Orfila, Decandolle, and Greville, have laid down general directions for distinguishing the esculent from the poisonous varieties; but it is extremely questionable whether their rules are always safe; and certainly they are not always accurate, as they would exclude many species in common use on the continent. It appears that most fungi which have a warty cap, more especially fragments of membrane adhering to their upper surface, are poisonous. Heavy fungi, which have an unpleasant odour, especially if they emerge from a vulva or bag, are also generally hurtful. Of those which grow in woods and shady places a few are esculent, but most are unwholesome; and if moist on the surface they should be avoided. All those which grow in tufts or clusters from the trunks or stumps of trees ought likewise to be shunned. A sure test of a poisonous fungus is an astringent, styptic taste, and perhaps also a disagreeable, but certainly a pungent, odour. Some fungi possessing these properties have indeed found their way to the epicure's table; but they are of very questionable quality. Those whose substance becomes blue soon after being cut are invariably poisonous. Agarics of an orange or rose-red colour, and boleti which are coriaceous or corky, or which have a membranous collar round the stem, are also unsafe; but these rules are not universally applicable in other genera. Even the esculent mushrooms, if partially devoured and abandoned by insects, are avoided by some as having in all probability acquired injurious qualities which they