Student's Hand-book of Mushrooms of America, Edible and Poisonous - Part 35
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Part 35

Although cases are cited where this mushroom has been eaten without injury, its fatally poisonous effects have been too well and too often tested to allow of any doubt as to the danger of eating it, even in small quant.i.ties.

Amanita Frostiana, Frost's Amanita, is a much smaller species than A.

muscaria. It bears a very close resemblance to the Fly Amanita, and might easily be taken for a small form of the same. The cap is yellowish and warted, and specimens occur in which the stem and gills are slightly tinged with yellow. It is poisonous.

PLATE XV.

FIG. 8.--=Ag. (Amanita) phalloides= Fries (=Amanita phalloides=) =A. vernalis= Bolt., =A. verrucosus= Curtis. "_Poisonous Amanita_,"

"_Death Cup_."

POISONOUS.

Cap bell-shaped or ovate at first, then expanded, smooth, obtuse, viscid, margin even, creamy-white, brown, or greenish, without warts; flesh white; stem white, hollow or stuffed, bulbous at the base, annulate; gills rounded and ventricose, coa.r.s.e, and persistently white, free from the stem; volva conspicuous, large, loose, adhering to the base, but free from the stem at the top, with the margin irregularly notched. In the white forms there is frequently a greenish or yellow tinge at the disk or centre of the cap. The white form is most common, but the brownish is often found in this country. I have not yet found the green-capped variety sometimes figured in European works. In the brown variety the stem and ring are often tinged with brown, as also the volva. The cap is usually from 2 to 3 inches broad, and the stem from 3 to 5 inches long. The whole plant is symmetrical in shape and clean looking, though somewhat clammy to the touch when moist. It is very common in mixed woods, in some localities, and is universally considered as fatally poisonous.

The white form of A. _phalloides_, although in reality bearing very little resemblance to the common field mushroom, has been mistaken for it as also for the _Smooth white lepiota_, and in some instances has been eaten with fatal results by those who gathered it.

The distinction between this most poisonous Amanita and the common field mushroom is well marked. In the common mushroom the _gills_ are _pink, becoming dark brown_, the _spores purplish brown_, and the whole mushroom is stout and short stemmed, the stem being shorter than the diameter of the cap, and having no volva, or wrapper at its base. In the species A. _phalloides_ the _gills_ are _persistently white_ and the bulb is distinct and broad at the base, the white cup-shaped wrapper sheathing the base of the stem like the calyx of a flower. The _Smooth white lepiota_ shows neither volva nor trace of one, and has other distinct characteristics which distinguish it from A. _phalloides_. See page 14, No. 4 of this series.

The specimen figured in Plate XV grew in Maryland, where it is quite common.

PLATE XV.

FIG. 9.--=Ag. (Amanita) mappa (Amanita mappa)= Linn., =Amanita citrina=, =A. virosa.=

POISONOUS.

Cap at first convex, then expanded, dry, without a separable cuticle, not warty but showing white, yellowish, or brownish scales or patches on its upper surface; gills white, adnexed; flesh white, sometimes slightly yellowish under the skin; stem stuffed, then hollow, cylindrical, yellowish white, nearly smooth, with a distinctly bulbous base; volva white or brownish. Odor pleasant. Spores spheroidal. The cap in this species is somewhat variable in color, but those having a white cap are most common. The plant is not so tall as those of the species _phalloides_. It is solitary in habit, and is found usually in open woods.

Curtis and Lowerby figure _mappa_ and _phalloides_ under the same name.

[Ill.u.s.tration: Plate XVI.

Fig. 1. Ag. (Amanita) vernus, Bull. (Amanita verna.) "Spring Mushroom."

Fig. 2. Represents section of mature plant.

Fig. 3. Spores; Fig. 4. Young plant.

POISONOUS.

T. Taylor, del.]

PLATE XVI.

FIGS. 1 to 4.--=Ag. (Amanita) vernus= Bull. =(Amanita verna)= Linn., =Amanita bulbosa=, =Ag. solitarius.= "_Vernal Mushroom_," "_Spring Mushroom_," etc.

POISONOUS.

Cap at first ovate, then expanded, becoming at length slightly depressed, viscid, white; margin smooth; flesh white; gills white, free; stem white, equal, stuffed or hollow, easily splitting, floccose, with bulbous base; volva white, closely embracing the stem, but free from it at the margin; ring reflexed; spores globose, .0003 in. broad. The plant is creamy white throughout and does not seem to be easily distinguishable from the white forms of A. _phalloides_. Fries and some others consider this species merely a variety of Amanita _phalloides_, and it is regarded as equally poisonous, the poisonous principle being the same as that of A. _phalloides_. It is very common in mixed woods from early spring to frosty weather.

ALKALOIDS OF THE POISONOUS MUSHROOMS.

Schrader, after some experiments made in 1811, stated that the poisonous principle of the "Fly mushroom," Amanita muscaria, seemed to be combined with its red coloring matter and might be extracted by water or aqueous alcohol, but that it was not soluble in ether.

Vaquelin, as the result of more extended investigations made in 1813, expressed the opinion that this poison was not confined to the coloring matter of the mushroom, but that it was an integral part of the fatty const.i.tuents not only of _muscaria_ but of several species of mushrooms.

In 1826 and 1830, and again in 1867, important investigations were made and published by Letellier relating to the medical and poisonous properties of mushrooms growing around Paris. Letellier's early investigations led him to the conclusion that there were two poisons contained in certain fungi--(1) an acrid principle easily destroyed by drying or boiling or by maceration in alcohol or in alkaline solution, and (2) a peculiar poisonous alkaloid found only in certain of the Amanita group. Letellier in 1866 named this latter alkaloid _amanitin_.

He then considered it to be the active poison of Amanita _muscaria_, Amanita _phalloides_, and Amanita _verna_, but a subsequent a.n.a.lysis by the German chemists Schmiedeberg and Koppe showed the _amanitin_ of Letellier to be identical with _cholin_, a substance found in bile.

Kobert says that _amanitin_ is non-poisonous in itself, but states that it may be changed on decay of the mushroom to the muscarin-like acting _neurin_, which is highly poisonous. He thinks it highly probable that nearly all of the edible and non-edible mushrooms contain pure _amanitin_ (cholin) partly in primitive condition and partly in a more intricate organic connection, as _lecithin_. It has been demonstrated that amanitin separates very readily from lecithin during the _decay or careless drying_ of mushrooms and changes into the _poisonous neurin_; hence the necessity of using mushrooms only when _perfectly fresh_ or when _quickly dried_.

MUSCARIN.[A]

[A] The earliest account of the separation of the poisonous principles of the mushrooms of the genus Amanita dates back to the experiments of Apoiger in 1851. Harnack's researches were published in 1876 and those of Huseman in 1882.

To the eminent German chemists Schmiedeberg and Koppe is due the credit of isolating the active poisonous principle of the Fly mushroom (_muscarin_). These authors published in 1869 a series of interesting experiments made with _muscarin_, having relation to its effect upon the heart, respiration, secretions and digestive organs, etc., and this was supplemented by other experiments made by their pupils, Prof. R. Boehm and E. Harnack. Schmiedeberg and Koppe's work relates to the effect of this poison on man as well as upon the lower animals. Dr. J. L. Prevost in 1874 reviewed the investigations made by Schmiedeberg and Koppe in a paper read before the Biological Society of Geneva, adding some confirmatory observations of his own relative to experiments made with muscarin upon the lower animals. The experiments made by these authors demonstrated "that muscarin arrests the action of a frog's heart, that a muscarined frog's heart began to beat immediately under the influence of atropin, and further that it was impossible to muscarine a frog's heart while under the influence of atropin."

Schmiedeberg subjected cats and dogs to doses of muscarin, large enough to produce death, and when the animals were about to succ.u.mb, injected hypodermically from one to two milligrams of sulphate of _atropin_, after which the toxic symptoms disappeared and the animals completely revived. Prof. Boehm found that _digitalin_ likewise re-established heart action when suspended by the action of muscarin.

In man the fatal termination, in cases of mushroom poisoning, where the antidote is not used, may take place in from 5 to 12 hours or not for two or three days.

According to Prof. E. Kobert's recent chemical a.n.a.lysis, the "Fly mushroom," Amanita muscaria, contains not only the very poisonous alkaloid _muscarin_ and the _amanitin_ of Letellier (_cholin_), but also a third alkaloid, _pilz atropin_. The pilz-atropin (mushroom atropin) was discovered by Schmiedeberg in a _commercial_ preparation of _muscarin_, and later Prof. Kobert discovered it in varying proportions in fresh mushrooms of different species. The effect of this third alkaloid, it is claimed, is to neutralize to a greater or less extent the effect of the poisonous one. Under its influence, when present in quant.i.ty, the poison is almost entirely neutralized. Contraction of the pupils changes to dilation, and slowing of the pulse may disappear. Only through the presence of this natural antidote in the Fly mushroom, says Kobert, is it possible, as in some parts of France and Russia, to eat without danger this mushroom, which contains 10% of sugar (trehalose or mycose) in a fermented and unfermented condition. He states also that delirium, intoxication, and other symptoms which, according to Prof.

Dittmer of Kamschatka and various scientific travellers, are reported effects of the Fly mushroom in the extreme north, are not experienced in the same degree in southern Russia. This difference in action, he thinks, may be very properly attributed to the varying proportion of the above-mentioned atropin in the mushroom or to the presence of substances which develop only in the extreme north.

The symptoms of _muscarin_ poisoning, apart from vomiting and purging, are slowing of the pulse, cerebral disturbance, contraction of the pupils, salivation and sweating. In case of death, which is caused by suffocation or a suspension of heart action, the lungs are found to be filled with air, and there is a transfusion of blood in the alimentary ca.n.a.l.

Prof. R. Kobert, in a lecture delivered before the University of Dorpat in 1891, states that _muscarin_ is found equally in the Fly mushroom (A.

muscaria), the Panther mushroom (A. pantherinus), Boletus luridus, and in varying quant.i.ties in Russula emetica. He states also that though highly poisonous to vertebrates, _muscarin_ is not so to flies, and that the noxious principle in A. muscaria which kills the flies is not as yet determined.

It has been shown that the lower animals, such as sheep and geese, as well as man, have been severely poisoned by feeding on the "Fly mushroom," and that in the case of the horse, experiments have demonstrated that even 0.04 of a gramme, 0.62 of a grain, have caused marked symptoms of poisoning.

For _muscarin_ as for _neurin_ poisoning the antidote is atropin administered internally or by subcutaneous injection.

PHALLIN.

The toxic alkaloid of Amanita _phalloides_ Fries (Amanita _bulbosa_) was examined by Boudier, who named it "_bulbosin_," and by Ore, who named it "_phalloidin_," but their examinations, it is claimed, proved little beyond the fact that it seemed to be in the nature of an alkaloid, identical neither with _muscarin_ nor _helvellic_ acid.

Ore affirmed that the _phalloidin_ of the Amanita phalloides was very nearly related to, and perhaps identical with, strychnine. From this view Kobert and others dissent.

The poisonous principle of Amanita _phalloides_ has recently been subjected to very careful a.n.a.lysis by Prof. Kobert. As a result of a large number of experiments and post-mortem examinations held on persons poisoned by A. _phalloides_, Kobert states that the symptoms can be explained uniformly by the action of a poison, to which he gives the provisional name of "_phallin_." This is an alb.u.minous substance which dissolves the corpuscles of the blood, resembling in this and other respects in a remarkable degree the action of _helvellic_ acid.

According to Kobert _phallin_ has so far only been found in Amanita _phalloides_ and in its varieties _verna_, _mappa_, etc. He finds also in this mushroom muscarin and an atropin-like alkaloid.

The symptoms of the phalloides poisoning are complex. Vomiting is accompanied by diarrhoea, cold sweats, fainting at times, convulsions, ending in coma. There is also fever and a quickening of the pulse. All these symptoms, which follow in succession, according to one author, are dependent on two different poisonous substances. The first may be an acrid and fixed poison, for it is found after repeated dryings, as well in the aqueous as in the alcoholic extract. The second acts by absorption, and is purely narcotic.

Phallin has some of the properties of the toxalb.u.min of poisonous spiders, and is a vegetable toxalb.u.min.

It has been remarked that in cases of poisoning by A. _phalloides_, the mushroom has tasted very good, and those poisoned felt well for several hours after eating.

Phalloides poisoning is said to bear a marked resemblance to phosphorus poisoning and to acute jaundice. There is no known antidote to the poisonous alkaloid _phallin_.