Studies of American Fungi. Mushrooms, Edible, Poisonous, etc. Part 1

Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.

by George Francis Atkinson, et al.

INTRODUCTION.

Since the issue of my "Studies and Ill.u.s.trations of Mushrooms," as Bulletins 138 and 168 of the Cornell University Agricultural Experiment Station, there have been so many inquiries for them and for literature dealing with a larger number of species, it seemed desirable to publish in book form a selection from the number of ill.u.s.trations of these plants which I have acc.u.mulated during the past six or seven years. The selection has been made of those species representing the more important genera, and also for the purpose of ill.u.s.trating, as far as possible, all the genera of agarics found in the United States. This has been accomplished except in a few cases of the more unimportant ones. There have been added, also, ill.u.s.trative genera and species of all the other orders of the higher fungi, in which are included many of the edible forms.

The photographs have been made with great care after considerable experience in determining the best means for reproducing individual, specific, and generic characters, so important and difficult to preserve in these plants, and so impossible in many cases to accurately portray by former methods of ill.u.s.tration.

One is often asked the question: "How do you tell the mushrooms from the toadstools?" This implies that mushrooms are edible and that toadstools are poisonous, and this belief is very widespread in the public mind.

The fact is that many of the toadstools are edible, the common belief that all of them are poisonous being due to unfamiliarity with the plants or their characteristics.

Some apply the term mushroom to a single species, the one in cultivation, and which grows also in fields (_Agaricus campestris_), and call all others toadstools. It is becoming customary with some students to apply the term mushroom to the entire group of higher fungi to which the mushroom belongs (_Basidiomycetes_), and toadstool is regarded as a synonymous term, since there is, strictly speaking, no distinction between a mushroom and a toadstool. There are, then, edible and poisonous mushrooms, or edible and poisonous toadstools, as one chooses to employ the word.

A more pertinent question to ask is how to distinguish the edible from the poisonous mushrooms. There is no single test or criterion, like the "silver spoon" test, or the criterion of a scaly cap, or the presence of a "poison cup" or "death cup," which will serve in all cases to distinguish the edible from the poisonous. Two plants may possess identical characters in this respect, i. e., each may have the "death cup," and one is edible while the other is poisonous, as in _Amanita caesarea_, edible, and _A. phalloides_, poisonous. There are additional characters, however, in these two plants which show that the two differ, and we recognize them as two different species.

To know several different kinds of edible mushrooms, which occur in greater or less quant.i.ty through the different seasons, would enable those interested in these plants to provide a palatable food at the expense only of the time required to collect them. To know several of the poisonous ones also is important, in order certainly to avoid them.

The purpose of this book is to present the important characters which it is necessary to observe, in an interesting and intelligible way, to present life-size photographic reproductions accompanied with plain and accurate descriptions. By careful observation of the plant, and comparison with the ill.u.s.trations and text, one will be able to add many species to the list of edible ones, where now perhaps is collected "only the one which is pink underneath." The chapters 17 to 21 should also be carefully read.

The number of people in America who interest themselves in the collection of mushrooms for the table is small compared to those in some European countries. The number, however, is increasing, and if a little more attention were given to the observation of these plants and the discrimination of the more common kinds, many persons could add greatly to the variety of their foods and relishes with comparatively no cost.

The quest for these plants in the fields and woods would also afford a most delightful and needed recreation to many, and there is no subject in nature more fascinating to engage one's interest and powers of observation.

There are also many important problems for the student in this group of plants. Many of our species and the names of the plants are still in great confusion, owing to the very careless way in which these plants have usually been preserved, and the meagerness of recorded observations on the characters of the fresh plants, or of the different stages of development. The study has also an important relation to agriculture and forestry, for there are numerous species which cause decay of valuable timber, or by causing "heart rot" entail immense losses through the annual decretion occurring in standing timber.

If this book contributes to the general interest in these plants as objects of nature worthy of observation, if it succeeds in aiding those who are seeking information of the edible kinds, and stimulates some students to undertake the advancement of our knowledge of this group, it will serve the purpose the author had in mind in its preparation.

I wish here to express my sincere thanks to Mrs. Sarah Tyson Rorer for her kindness in writing a chapter on recipes for cooking mushrooms, especially for this book; to Professor I. P. Roberts, Director of the Cornell University Agricultural Experiment Station, for permission to use certain of the ill.u.s.trations (Figs. 1--7, 12--14, 31--43) from Bulletins 138 and 168, Studies and Ill.u.s.trations of Mushrooms; to Mr. F.

R. Rathbun, for the charts from which the colored plates were made; to Mr. J. F. Clark and Mr. H. Ha.s.selbring, for the Chapters on Chemistry and Toxicology of Mushrooms, and Characters of Mushrooms, to which their names are appended, and also to Dr. Chas. Peck, of Albany, N. Y., and Dr. G. Bresadola, of Austria-Hungary, to whom some of the specimens have been submitted.

GEO. F. ATKINSON, Ithaca, N. Y., October, 1900.

Cornell University.

SECOND EDITION.

In this edition have been added 10 plates of mushrooms of which I did not have photographs when the first edition was printed. It was possible to accomplish this without changing the paging of any of the descriptive part, so that references to all of the plants in either edition will be the same.

There are also added a chapter on the "Uses of Mushrooms," and an extended chapter on the "Cultivation of Mushrooms." This subject I have been giving some attention to for several years, and in view of the call for information since the appearance of the first edition, it seemed well to add this chapter, ill.u.s.trated by several flashlight photographs.

G. F. A.

September, 1901.

CHAPTER I.

FORM AND CHARACTERS OF THE MUSHROOM.

=Value of Form and Characters.=--The different kinds of mushrooms vary in form. Some are quite strikingly different from others, so that no one would have difficulty in recognizing the difference in shape. For example, an umbrella-shaped mushroom like the one shown in Fig. 1 or 81 is easily distinguished from a shelving one like that in Fig. 9 or 188.

But in many cases different species vary only slightly in form, so that it becomes a more or less difficult matter to distinguish them.

In those plants (for the mushroom is a plant) where the different kinds are nearly alike in form, there are other characters than mere general form which enable one to tell them apart. These, it is true, require close observation on our part, as well as some experience in judging of the value of such characters; the same habit of observation and discrimination we apply to everyday affairs and to all departments of knowledge. But so few people give their attention to the discrimination of these plants that few know the value of their characters, or can even recognize them.

It is by a study of these especial characters of form peculiar to the mushrooms that one acquires the power of discrimination among the different kinds. For this reason one should become familiar with the parts of the mushroom, as well as those characters and markings peculiar to them which have been found to stamp them specifically.

=Parts of the Mushroom.=--To serve as a means of comparison, the common pasture mushroom, or cultivated form (_Agaricus campestris_), is first described. Figure 1 ill.u.s.trates well the princ.i.p.al parts of the plant; the cap, the radiating plates or gills on the under side, the stem, and the collar or ring around its upper end.

=The Cap.=--The cap (technically the _pileus_) is the expanded part of the mushroom. It is quite thick, and fleshy in consistency, more or less rounded or convex on the upper side, and usually white in color. It is from 1--2 cm. thick at the center and 5--10 cm. in diameter. The surface is generally smooth, but sometimes it is torn up more or less into triangular scales. When these scales are prominent they are often of a dark color. This gives quite a different aspect to the plant, and has led to the enumeration of several varieties, or may be species, among forms accredited by some to the one species.

=The Gills.=--On the under side of the pileus are radiating plates, the gills, or _lamellae_ (sing. _lamella_). These in shape resemble somewhat a knife blade. They are very thin and delicate. When young they are pink in color, but in age change to a dark purple brown, or nearly black color, due to the immense number of spores that are borne on their surfaces. The gills do not quite reach the stem, but are rounded at this end and so curve up to the cap. The triangular s.p.a.ces between the longer ones are occupied by successively shorter gills, so that the combined surface of all the gills is very great.

[Ill.u.s.tration: FIGURE. 1.--Agaricus campestris. View of under side showing stem, annulus, gills, and margin of pileus. (Natural size.)]

=The Stem or Stipe.=--The stem in this plant, as in many other kinds, is attached to the pileus in the center. The purpose of the stem seems quite surely to be that of lifting the cap and the gills up above the ground, so that the spores can float in the currents of air and be readily scattered. The stem varies in length from 2--10 cm. and is about 1--1-1/2 cm. in diameter. It is cylindrical in form, and even, quite firm and compact, though sometimes there is a central core where the threads are looser. The stem is also white and fleshy, and is usually smooth.

=The Ring.=--There is usually present in the mature plant of _Agaricus campestris_ a thin collar (_annulus_) or ring around the upper end of the stem. It is not a movable ring, but is joined to the stem. It is very delicate, easily rubbed off, or may be even washed off during rains.

=Parts Present in Other Mushrooms--The Volva.=--Some other mushrooms, like the _deadly Amanita_ (_Amanita phalloides_) and other species of the genus _Amanita_, have, in addition to the cap, gills, stem, and ring, a more or less well formed cup-like structure attached to the lower end of the stem, and from which the stem appears to spring. (Figs.

55, 72, etc.) This is the _volva_, sometimes popularly called the "death cup," or "poison cup." This structure is a very important one to observe, though its presence by no means indicates in all cases that the plant is poisonous. It will be described more in detail in treating of the genus _Amanita_, where the ill.u.s.trations should also be consulted.

[Ill.u.s.tration: FIGURE 2.--Agaricus campestris. "b.u.t.tons" just appearing through the sod. Some sp.a.w.n at the left lower corner. Soil removed from the front. (Natural size.)]

=Presence or Absence of Ring or Volva.=--Of the mushrooms which have stems there are four types with respect to the presence or absence of the ring and volva. In the first type both the ring and volva are absent, as in the common fairy ring mushroom, _Marasmius oreades_; in the genus _Lactarius_, _Russula_, _Tricholoma_, _c.l.i.tocybe_, and others.

In the second type the ring is present while the volva is absent, as in the common mushroom, _Agaricus campestris_, and its close allies; in the genus _Lepiota_, _Armillaria_, and others. In the third type the volva is present, but the ring is absent, as in the genus _Volvaria_, or _Amanitopsis_. In the fourth type both the ring and volva are present, as in the genus _Amanita_.

=The Stem is Absent in Some Mushrooms.=--There are also quite a large number of mushrooms which lack a stem. These usually grow on stumps, logs, or tree trunks, etc., and one side of the cap is attached directly to the wood on which the fungus is growing. The pileus in such cases is lateral and shelving, that is, it stands out more or less like a shelf from the trunk or log, or in other cases is spread out flat on the surface of the wood. The shelving form is well shown in the beautiful _Claudopus nidulans_, sometimes called _Pleurotus nidulans_, and in other species of the genus _Pleurotus_, _Crepidotus_, etc. These plants will be described later, and no further description of the peculiarities in form of the mushrooms will be now attempted, since these will be best dealt with when discussing species fully under their appropriate genus.

But the brief general description of form given above will be found useful merely as an introduction to the more detailed treatment. Chapter XXI should also be studied. For those who wish the use of a glossary, one is appended at the close of the book, dealing only with the more technical terms employed here.

[Ill.u.s.tration: FIGURE 3.--Agaricus campestris. Soil washed from the "sp.a.w.n" and "b.u.t.tons," showing the young "b.u.t.tons" attached to the strands of mycelium. (1-1/4 natural size.)]

CHAPTER II.

DEVELOPMENT OF THE MUSHROOM.

When the stems of the mushrooms are pulled or dug from the ground, white strands are often clinging to the lower end. These strands are often seen by removing some of the earth from the young plant, as shown in Fig. 2. This is known among gardeners as "sp.a.w.n." It is through the growth and increase of this sp.a.w.n that gardeners propagate the cultivated mushroom. Fine specimens of the sp.a.w.n of the cultivated mushroom can be seen by digging up from a bed a group of very young plants, such a group as is shown in Fig. 3. Here the white strands are more numerous than can readily be found in the lawns and pastures where the plant grows in the feral state.

[Ill.u.s.tration: FIGURE 4.--Agaricus campestris. Sections of "b.u.t.tons" at different stages, showing formation of gills and veil covering them.

(Natural size.)]

=Nature of Mushroom Sp.a.w.n.=--This sp.a.w.n, it should be clearly understood, is not sp.a.w.n in the sense in which that word is used in fish culture; though it may be employed so readily in propagation of mushrooms. The sp.a.w.n is nothing more than the vegetative portion of the plant. It is made up of countless numbers of delicate, tiny, white, jointed threads, the _mycelium_.