Types of Edible Mushrooms

—While it is quite impossible for a manual of this kind to give any directions by which a person, not an expert, may make certain distinctions between the edible and poisonous varieties of mushrooms, it is thought advisable to give a fair technical illustration of the two classes. The common mushroom, Agaricus campestris, is shown in the accompanying Fig. 61,—three-fourths its natural size. The second specimen from the left is young and is in a state of development known as a button. The figure at the extreme left is a larger specimen, showing the slightly checked surface that sometimes occurs in this species. In fresh specimens the surface is white, but various shades of light brown, either checked or plain, are often found. The specimen at the right shows the gills on the lower surface of the cap. These gills in a newly expanded mushroom, fresh from the field, are of a beautiful delicate pale pink color, often with a touch of salmon. In the older samples the gills turn to a light brown and finally almost to a black color. This discoloration is chiefly due to the development of almost innumerable spores from which new plants are propagated. If the stem of a common mushroom be broken off and the cap be laid gills downward on a piece of white paper, the spores will drop off and after a few hours will appear as a brown dust. The usual diameter of full-grown specimens of this variety of mushroom is from 1⁄2 to 3 inches, though many smaller and many larger samples are found.

This variety of mushroom is the principal one which is exposed upon the markets of Washington. They are especially abundant in the autumn after copious rains often succeeding the usual period of drought in that region. October is the banner month for this variety of mushroom. The mycelium from which the autumn mushroom grows is formed in the spring, and after the dry period of summer the little spheroid granules formed upon the mycelium are capable of absorbing the moisture of the warm autumnal rains and rapidly expand to the full-grown mushroom. After all the conditions of growth are fulfilled it usually requires only a single night for a button to push through the surface of the soil and expand its cap. Mushrooms are particularly obnoxious to the ravages of insects, and it is always advisable that they should be gathered and eaten immediately after they are formed. The insect larvæ attack the mature mushroom, travelling up through the stem into the cap, and decomposition rapidly follows.

It is easy to determine whether a mushroom is wormy or not by breaking off the stem close to the cap and observing if there are little holes through which the larvæ have passed upward into the cap. The common mushroom occurs most frequently on lawns and in pastures, and especially in neglected fields where weeds have been succeeded by a scant covering of grass. Sometimes during the spring and summer, as well as in the autumn, the common mushroom is found upon the market. These mushrooms usually are produced upon the garbage dumping grounds near the city. The garbage and refuse from the city furnish the manurial conditions required for a speedy development of the mushroom from the mycelium.

The Horse Mushroom (Agaricus arvensis Schaeff.).

—This variety of mushroom is also one which grows in great abundance in the neighborhood of Washington and in other latitudes affording a similar environment. This specimen is in many respects like Agaricus campestris but the surface of the cap is somewhat darker colored. The ring on the stem is also wider and thicker than in campestris. This variety also grows larger than campestris, and the diameter of the cap is commonly from three to six inches. The figure is only about one-half the natural size. The horse mushroom is frequently confounded with the common mushroom, and there is practically no difference in their edible qualities. It grows preferably in gardens rather than fields, and especially in gardens which have been heavily fertilized. It also frequently appears in old beds composed of decayed stable manure which has been used for forcing beds for early vegetables.

Shaggy Mushroom (Coprinus comatus Fr.).

—The accompanying Fig. 63 represents a group of three specimens of this variety of mushroom growing from a single base. The largest one is already showing signs of liquefaction and decomposition and a part of the cap has already disappeared. One of the peculiarities of this species is that beginning with the edge of the cap the whole mushroom dissolves sometimes within a day, when it is full grown, into an inky-black fluid. A portion of this inky fluid has run partly down the white stem of the largest mushroom. The cap of this mushroom, except when it begins to liquefy, resembles somewhat the form of a partially closed umbrella. In the early stages of growth the cap, gills, and stem are white, except the apex of the cap, which is generally dark-colored. The surface of the cap is covered with delicate lacerated scales, the characteristic from which the name comatus or shaggy is derived. The juice from the fresh sample is colorless as water. When it first begins to turn it is wine-colored, and until the juice is very deeply discolored the sample is still edible. After the juice has turned completely black it is considered too old to be eaten. This species of mushroom grows best in shady places, in a soil well supplied with humus. The season in which this variety of mushroom is most abundant is late in the autumn or early in the winter, when the nights are cold but the ground is not yet frozen. The liquefaction and decay of this mushroom come on so quickly that it is not usually infested with larvæ which do not have time to develop before the mushroom is reduced to a shapeless mass. The most common organism found is the myriapod, a thousand-legged worm, which often finds its way between the gills and stem. This cavity should always be examined for worms of this kind when the mushroom is being prepared for the table.

Fairy Ring Mushroom (Marasmius oreades Fr.).

—This variety is one which is interesting both on account of its edible properties and by reason of the circular areas in which it often grows. This illustration is about three-fourths of the natural size. The tendency of this variety to grow in the annual form designated is beautifully shown in the accompanying figure, from a photograph taken on the grounds of the Department of Agriculture. The ring in question is seven feet in diameter and the photograph was taken early in November. The stem in this variety has no ring,—the gills are few and widely separated and the cap as it becomes fully expanded has a peculiar knob-like projection in the center. This gives a characteristic appearance to this variety of mushroom. The cap and stem are colored a pinkish-buff, and the gills have a lighter shade of the same color varying in early growth toward a cream tint. The spores are white and can be observed by placing the cap, as already indicated, on a dark-colored paper, preferably black glazed paper. The fairy ring mushroom is one of the commonest species which grows on the lawns in Washington and vicinity. As many as twenty of these fairy rings have been found on the grounds of the Department of Agriculture in one season. In the earlier days, when superstition was more rife than at present, these rings were supposed to mark the places of the dances of the fairies. Another fanciful cause assigned for the production of the rings was that it was due to the effect of lightning striking the ground and burning the grass in a circle, and thus favoring the growth of fungi. Investigations, however, show that the fairy ring is due to a peculiar way in which the mycelium is produced, which begins at a central point, growing uniformly in all directions a few inches each year. After a while the central portion, being older, begins to die, and thus a small circular band is formed which each year increases in size, growing regularly on the outside and dying as regularly on the inside. The fairy rings are not always complete circles,—they are sometimes broken and often are crescent-shaped. This variety of mushroom is quite permanent, does not tend to decay as rapidly as some, and resists better than most varieties the attacks of insects. They, however, are very small as compared with the other common varieties.

Puff-balls.

—A typical mushroom known as the puff-ball is the variety known as Lycoperdon cyathiforme Bosc. The puff-ball is so plain in its form that a description of its appearance is difficult. Usually the outside is colored brown and the covering is more or less irregularly checked, the white color of the interior showing between the darker, elevated areas. When still quite young the flesh is solid, of a milk-white color, and apparently quite dry. After two or three days it becomes soft, has a yellowish tint, develops a watery and later an amber-colored juice as it continues its development through to the later stages. If the mushroom remains ungathered, the interior dries up into a fine brown powder which is projected into the air when pressed by the finger. It is often blown away by the wind. When the fungus reaches this stage of decay it is very commonly known as “the devil’s snuff-box.” Finally the spores and other dust-like bodies are blown away, and there is left only a dry and leathery framework. In the latter stages the puff-ball is not regarded as edible, not because of its being poisonous, but on account of its dry and leathery consistency. In the neighborhood of Washington puff-balls are found commonly in the autumn on lawns and in gardens, and especially on vacant lots where the soil has remained uncultivated and been closely grazed by cattle. The puff-ball also tends to grow in a fairy ring form, and in the circular area in which it grows the grass is likely to be darker in color, showing the existence of a richer soil. It is only while the interior of the puff-ball is still solid and white, with something like the texture of cheese, that it has its highest edible properties.

Cepe (Boletus edulis Bull.).

—This variety of mushroom is one of the most highly esteemed, especially in the south of France. It is large and has a very large, half-pear shaped stem. The flesh of this variety of mushroom is white and quite firm in the young mushroom, but becomes softer with age and assumes on the outside a wine tint. It grows, especially in the late summer and through the autumn, wild in the forest. In the extreme south of France it sometimes appears as early as April. (“Nouvel Atlas de Champignons,” Paul Dumée, page 45.) (“The Mushroom Book,” by Nina L. Marshall, page 109.) The cap is usually from four to six inches in diameter and is a gray, brownish-red or tawny-brown in color.

The Fly Amanita (Amanita muscaria (L.) Fr.).

—This is one of the very poisonous varieties of mushrooms. In the illustration the fully matured mushroom is shown at one-half its natural size. This is the most common poisonous mushroom which grows in the District of Columbia and other nearby localities. The points especially to be noticed are the bulbous enlargement at the base of the stem, breaking into thick scales above, the very broad drooping ring near the top of the stem, and the corky particles loosely attached to the smooth, glossy upper surface of the cap. The stem, gills, and the spores are white, the corky particles commonly of a buff color, but sometimes varying almost to white. The glossy upper surface of the cap, beneath the corky particles, varies from a brilliant red to orange-yellow, buff, and even white. Commonly in the vicinity of Washington the coloration is orange in the center, shading to yellow toward the margin. Brilliant red ones are rarely seen in this locality, but white ones are not infrequent, especially late in the season. This was the variety of mushroom that lately caused the death of a well known man in Washington. This poisonous variety is one of the largest, handsomest, and most dangerous of mushrooms, and is one whose poisonous character has been most fully studied. It is abundant in the vicinity of Washington in the fall, growing chiefly in the pine woods and, especially, in the localities which have been frequented by hogs. The chief active poisonous principle of the fly amanita is an alkaloid called muscarine, but other poisonous substances whose exact nature has not yet been discovered also occur in the plant.

When this variety of mushroom is reduced to a paste and exposed where it can be eaten by flies the latter are readily poisoned, and hence the common name of “fly amanita.”