Chapter 6

THE PURPLE-BROWN-SPORED AGARICS.[B]

The members of this subdivision are recognized at maturity by the purple-brown, dark brown or nearly black spores when seen in mass. As they ripen on the surface of the gills the large number give the characteristic color to the lamellæ. Even on the gills the purple tinge of the brown spores can often be seen. The color is more satisfactorily obtained when the spores are caught in mass by placing the cap, gills downward, on white paper.

AGARICUS Linn. (PSALLIOTA Fr.)

In the genus _Agaricus_ the spores at maturity are either purple-brown in mass or blackish with a purple tinge. The annulus is present on the stem, though disappearing soon in some species, and the stem is easily separated from the substance of the pileus. The gills are free from the stem, or only slightly adnexed. The genus is closely related to _Stropharia_ and the species of the two genera are by some united under one genus (_Psalliota_, Hennings). Peck, 36th Report, N. Y. State Mus., p. 41--49, describes 7 species. Lloyd Mycol. Notes, No. 4, describes 8 species. C. O. Smith, Rhodora, I: 161--164, 1899, describes 8 species.

=Agaricus (Psalliota) campestris= Linn. =Edible.=--This plant has been quite fully described in the treatment of the parts of the mushroom, and a recapitulation will be sufficient here. It grows in lawns, pastures, by roadsides, and even in gardens and cultivated fields. A few specimens begin to appear in July, it is more plentiful in August, and abundantly so in September and October. It is 5--8 cm. high (2--3 inches), the cap is 5--12 cm. broad, and the stem 8--12 mm. in thickness.

The =pileus= is first rounded, then convex and more or less expanded. The surface at first is nearly smooth, presenting a soft, silky appearance from numerous loose fibrils. The surface is sometimes more or less torn into triangular scales, especially as the plants become old. The color is usually white, but varies more or less to light brown, especially in the scaly forms, where the scales may be quite prominent and dark brown in color. Sometimes the color is brownish before the scales appear. The flesh is white. The =gills= in the young button stage are white. They soon become pink in color and after the cap is expanded they quickly become purple brown, dark brown, and nearly black from the large number of spores on their surfaces. The gills are free from the stem and rounded behind (near the stem). The =stem= is white, nearly cylindrical, or it tapers a little toward the lower end. The flesh is solid, though the central core is less firm. The =veil= is thin, white, silky, and very frail. It is stretched as the cap expands and finally torn so that it clings either as an annulus around the stem, or fragments cling around the margin of the cap. Since the =annulus= is so frail it shrivels as the plant ages and becomes quite inconspicuous or disappears entirely (see Figs. 1--7).

Variations in the surface characters of the cap and stem have led some to recognize several varieties. This is known as the common mushroom and is more widely known and collected for food than any other. It is also cultivated in mushroom houses, cellars, caves, abandoned mines, etc.

=Agaricus (Psalliota) rodmani= Pk. =Edible.=--Rodman's mushroom, _Agaricus rodmani_, grows in grassy places along streets of cities, either between the curbing and the walk, or between the curbing and the pavement. It is entirely white or whitish and sometimes tinged with yellowish at the center of the pileus. The plants are 4--8 cm. high, the cap 5--8 cm. broad and the stem 1--2 cm. in thickness.

The =pileus= is rounded, and then convex, very firm, compact and thick, with white flesh. The =gills= are crowded, first white, then pink, and in age blackish brown. The =stem= is very short, solid, nearly cylindrical, not bulbous. The =annulus= is quite characteristic, being very thick, with a short limb, and double, so that it often appears as two distinct rings on the middle or lower part of the stem as shown in Fig. 17. This form of the annulus is probably due to the fact that the thick part of the margin of the pileus during the young stage rests between the lower and upper part of the annulus, i. e., the thick veil is attached both to the inner and outer surface of the margin of the cap, and when it is freed by the expansion of the pileus it remains as a double ring. It is eagerly sought and much relished by several persons at Ithaca familiar with its edible qualities.

The plant closely resembles A. campestris var., edulis, Vittad. (See Plate 54, Bresadola, I Funghi Mangerecci e Velenosi, 1899) and is probably the same.

=Agaricus (Psalliota) arvensis= Schaeff. =Edible.=--The field mushroom, or horse mushroom, _Agaricus arvensis_, grows in fields or pastures, sometimes under trees and in borders of woods. One form is often white, or yellowish white, and often shows the yellow color when dried. The plant sometimes occurs in the form of a fairy ring as shown in Fig. 18. It is 5--12 cm. high, the cap from 5--15 cm. broad and the stem 8--15 mm. in thickness.

The =pileus= is smooth, quite thick and firm, convex to expanded. The =gills= are first white, then tinged with pink and finally blackish brown. The =stem= is stout, nearly cylindrical, hollow, bulbous. The veil is double like that of _Agaricus placomyces_, the upper or inner layer remaining as a membrane, while the lower or outer layer is split radially and remains in large patches on the lower surface of the upper membrane.

=Agaricus (Psalliota) silvicola= Vittad. =Edible.=--The _Agaricus silvicola_ grows in woods, groves, etc., on the ground, and has been found also in a newly made garden in the vicinity of trees near the woods. It is an attractive plant because of its graceful habit and the delicate shades of yellow and white. It ranges from 10--20 cm. high, the cap is 5--12 cm. broad and the stem 6--10 mm. in thickness.

The =pileus= becomes convex, and expanded or nearly flat, and often with an elevation or umbo in the center. It is thin, smooth, whitish and often tinged more or less deeply with yellow (sulfur or ochraceous) and is sometimes tinged with pink in the center. The flesh is whitish or tinged with pink. The =gills= when very young are whitish, then pink, and finally dark brown or blackish brown, much crowded, and distant from the stem. The =stem= is long, nearly cylindrical, whitish, abruptly enlarged below into a bulb. It is often yellowish below, and especially in drying becomes stained with yellow. The =ring= is thin, membranaceous, delicate, sometimes with broad, soft, floccose patches on the under side. The ring usually appears single, but sometimes the =veil= is seen to be double, and the outer or lower portion tends to split radially as in _A. arvensis_ or _A. placomyces_. This is well shown in large specimens, and especially as the veil is stretched over the gills as shown in Fig. 20.

From the form of the plant as well as the peculiarities of the veil in the larger specimens, it is related to _A. arvensis_ and _A. placomyces_, more closely to the former. It occurs during mid-summer and early autumn. Figure 10 is from plants (No. 1986 C. U. herbarium) collected in open woods at Ithaca.

=Agaricus (Psalliota) subrufescens= Pk. =Edible.=--The _Agaricus subrufescens_ was described by Dr. Peck from specimens collected on a compost heap composed chiefly of leaves, at Glen Cove, Long Island. It occurs sometimes in greenhouses. In one case reported by Peck it appeared in soil prepared for forcing cucumbers in a greenhouse in Washington, D. C.

According to the description the =pileus= becomes convex or broadly expanded, is covered with silky hairs and numerous minute scales. The color is whitish, grayish or dull reddish brown, the center being usually smooth and darker, while the flesh is white. The =gills= change from white to pinkish and blackish brown in age. The =stem= is long, nearly cylindrical or somewhat enlarged or bulbous at the base, first stuffed, then hollow, white. The =annulus= is thick, and the under side marked by loose threads or scales.

This plant is said to differ from the common mushroom (_A. campestris_) in the more deeply hemispherical cap of the young plant, the hollow and somewhat bulbous stem, and in the scales on the under side of the annulus. In fresh plants the flesh has also a flavor of almonds. It is closely related to =A. silvaticus= Schaeff., p. 62, T. 242, Icones Fung. Bav. etc., 1770, if not identical with it. _A. silvaticus_ has light ochraceous or subrufescent scales on the cap, a strong odor, and occurs in gardens as well as in the woods.

=Agaricus (Psalliota) fabaceus= Berk., was described in Hooker's London Journal of Botany, =6=: 314, 1847, from specimens collected in Ohio. The plant is white and is said to have a strong but not unpleasant odor. _Agaricus amygdalinus_ Curt., from North Carolina, and of which no description was published, was so named on account of the almond-like flavor of the plant. Dr. Farlow suggests (Proc. Bost. Soc. Nat. Hist. =26=: 356--358, 1894) that _A. fabaceus_, _amygdalinus_, and _subrufescens_ are identical.

=Agaricus (Psalliota) placomyces= Pk. =Edible.=--The flat-cap mushroom, _Agaricus placomyces_ Pk., occurs in borders of woods or under trees from June to September. According to Peck it occurs in borders of hemlock woods, or under hemlock trees. At Ithaca it is not always associated with hemlock trees. The largest specimens found here were in the border of mixed woods where hemlock was a constituent. It has been found near and under white pine trees in lawns, around the Norway spruce and under the Norway spruce. The plants are from 5--15 cm. high, the cap from 5--12 cm. in diameter, and the stem 6--8 mm. in thickness.

The =pileus= when young is broadly ovate, then becomes convex or fully expanded and flat in age, and is quite thin. The ground color is whitish, often with a yellowish tinge, while the surface is ornamented with numerous minute brownish scales which are scattered over a large part of the cap, but crowded or conjoined at the center into a large circular patch. This gives to the plant with its shapely form a beautiful appearance. In the young stage the entire surface of the pileus is quite evenly brown. As it expands the outer brown portion is torn asunder into numerous scales because the surface threads composing this brown layer cease to grow. These scales are farther apart toward the margin of the cap, because this portion of the cap always expands more than the center, in all mushrooms. The =gills= are at first white, or very soon pink in color, and in age are blackish brown. Spores 5--8 × 3--4 µ.

The =stem= is nearly cylindrical, hollow or stuffed, white or whitish, smooth, bulbous, and the bulb is sometimes tinged with yellow. The =veil= is very handsome, and the way in which the annulus is formed from it is very interesting. The veil is quite broad, and it is double, that is, it consists of two layers which are loosely joined by threads. In the young stage the veil lies between the gills and the lower two-thirds of the stem. As the pileus expands the lower (outer part) layer of the veil is torn, often in quite regular radiating portions, as shown in Fig. 22. An interesting condition of the veil is shown in the middle plant in Fig. 23. Here the outer or lower layer of the veil did not split radially, but remained as a tube surrounding the stem, while the two layers were separated, the inner one being still stretched over the gills. It is customary to speak of the lower part of the veil as the outer part when the cap is expanded and the veil is still stretched across over the gills, while the upper portion is spoken of as the inner layer or part. It is closely related to _A. arvensis_, and may represent a wood inhabiting variety of that species.

=Agaricus (Psalliota) comtulus= Fr.--This pretty little agaric seems to be rather rare. It was found sparingly on several occasions in open woods under pines at Ithaca, N. Y., during October, 1898. Lloyd reports it from Ohio (Mycolog. Notes, No. 56, Nov. 1899), and Smith from Vermont (Rhodora I, 1899). Fries' description (Epicrisis, No. 877) runs as follows: "Pileus slightly fleshy, convex, plane, obtuse, nearly smooth, with appressed silky hairs, stem hollow, sub-attenuate, smooth, white to yellowish, annulus fugacious; gills free, crowded, broad in front, from flesh to rose color. In damp grassy places. Stem 2 inches by 2 lines, at first floccose stuffed. Pileus 1--1-1/2 inch diameter. Color from white to yellowish."

The plants collected at Ithaca are illustrated in Fig. 24 from a photograph of plants (No. 2879 C. U. herbarium). My notes on these specimens run as follows: Plant 3--6 cm. high, pileus 1.5--3 cm. broad, stem 3--4 mm. in thickness. =Pileus= convex to expanded, fleshy, thin on the margin, margin at first incurved, creamy white with egg yellow stains, darker on the center, in age somewhat darker to umber or fuliginous, moist when fresh, surface soon dry, flesh tinged with yellow. The =gills= are white when young, then grayish to pale rose, and finally light purple brown, rounded in front, tapering behind (next the stem) and rounded, free from the stem, 4--5 mm. broad. =Basidia= clavate, 25--30 × 5--6 µ. =Spores= small, oval, 3--4 × 2--3 µ, in mass light purple brown. The =stem= tapers above, is sub-bulbous below, yellowish and stained with darker yellowish threads below the annulus, hollow, fibrous, fleshy. The =veil= whitish stained with yellow, delicate, rupturing irregularly, portions of it clinging to margin of the pileus and portions forming a delicate ring. When parts of the plant come in contact with white paper a blue stain is apt to be imparted to the paper, resembling the reaction of iodine on starch. This peculiarity has been observed also in the case of another species of _Agaricus_. The species is regarded with suspicion by some. I collected the plant also at Blowing Rock, N. C., in September, 1899. The caps of these specimens measure 4 cm. in diameter.

=Agaricus diminutivus= Pk., is a closely related species. It is distinguished chiefly by its somewhat larger size, and purplish to reddish brown hairs on the surface of the pileus, and by the somewhat larger spores, which, however, are small. I have found it at Ithaca, the surface of the pileus hairy, with beautiful, triangular, soft, appressed, purplish scales.

HYPHOLOMA Fr.

In the genus _Hypholoma_ the spores are purple brown, the gills attached to the stem, and the veil when ruptured clings to the margin of the cap instead of to the stem, so that a ring is not formed, or only rarely in some specimens. The stem is said to be continuous with the substance of the cap, that is, it is not easily separated from it. The genus is closely related to _Agaricus (Psalliota)_ and _Stropharia_, from both of which it differs in the veil not forming a ring, but clinging to the margin of the cap. It further differs from _Agaricus_ in the stem being continuous with the substance of the cap, while _Stropharia_ seems to differ in this respect in different species. The plants grow both on the ground and on wood. There are several species which are edible and are very common. Peck gives a synopsis of six species in the 49th Report New York State Mus., page 61, 1896, and Morgan describes 7 species in Jour. Cinn. Soc. Nat. Hist. =6=: 113--115.

=Hypholoma sublateritium= Schaeff. =Edible=, _bitter sometimes_. The name of this species is derived from the color of the cap, which is nearly a brick red color, sometimes tawny. The margin is lighter in color. The plants grow usually in large clusters on old stumps or frequently appearing on the ground from buried portions of stumps or from roots. There are from six to ten, or twenty or more plants in a single cluster. A single plant is from 8--12 cm. high, the cap is 5--8 cm. broad, and the stem 6--8 mm. in thickness.

The =pileus= is convex to expanded, smooth, or sometimes with loose threads from the veil, especially when young, even, dry. The flesh is firm, whitish, and in age becoming somewhat yellowish. The =gills= are adnate, sometimes decurrent by a little tooth, rather crowded, narrow, whitish, then dull yellow, and becoming dark from the spores, purplish to olivaceous. The =stem= usually tapers downward, is firm, stuffed, smooth, or with remnants of the veil giving it a floccose scaly appearance, usually ascending because of the crowded growth. The =veil= is thin and only manifested in the young stage of the plant as a loose weft of threads. As the cap expands the veil is torn and adheres to the margin, but soon disappears.

The flesh of this plant is said by European writers to be bitter to the taste, and it is regarded there as poisonous. This character seems to be the only distinguishing one between the _Hypholoma sublateritium_ Schaeff., of Europe, and the _Hypholoma perplexum_ Pk., of this country which is edible, and probably is identical with _H. sublateritium_. If the plant in hand agrees with this description in other respects, and is not bitter, there should be no danger in its use. According to Bresadola, the bitter taste is not pronounced in _H. sublateritium_. The taste probably varies as it does in other plants. For example, in _Pholiota præcox_, an edible species, I detected a decided bitter taste in plants collected in June, 1900. Four other persons were requested to taste the plants. Two of them pronounced them bitter, while two did not detect the bitter taste.

There is a variety of _Hypholoma sublateritium_, with delicate floccose scales in concentric rows near the margin of the cap, called _var. squamosum_ Cooke. This is the plant illustrated in Fig. 25, from specimens collected on rotting wood in the Cascadilla woods, Ithaca, N. Y. It occurs from spring to autumn.

_Hypholoma epixanthum_ Fr., is near the former species, but has a yellow pileus, and the light yellow gills become gray, not purple.

=Hypholoma appendiculatum= Bull. =Edible.=--This species is common during late spring and in the summer. It grows on old stumps and logs, and often on the ground, especially where there are dead roots. It is scattered or clustered, but large tufts are not formed as in _H. sublateritium_. The plants are 6--8 cm. high, the cap 5--7 cm. broad, and the stem 4--6 mm. in thickness.

The =pileus= is ovate, convex to expanded, and often the margin elevated, and then the cap appears depressed. It is fleshy, thin, whitish or brown, tawny, or with a tinge of ochre, and becoming pale in age and when dry. As the plant becomes old the pileus often cracks in various ways, sometimes splitting radially into several lobes, and then in other cases cracking into irregular areas, showing the white flesh underneath. The surface of the pileus when young is sometimes sprinkled with whitish particles giving it a mealy appearance. The =gills= are attached to the stem, crowded, becoming more or less free by breaking away from the stem, especially in old plants. They are white, then flesh colored, brownish with a slight purple tinge. The =stem= is white, smooth, or with numerous small white particles at the apex, becoming hollow. The =veil= is very delicate, white, and only seen in quite young plants when they are fresh. It clings to the margin of the cap for a short period, and then soon disappears.

Sometimes the pileus is covered with numerous white, delicate floccose scales, which give it a beautiful appearance, as in Fig. 26, from specimens (No. 3185 C. U. herbarium), collected on the campus of Cornell University among grass. The entire plant is very brittle, and easily broken. It is tender and excellent for food. I often eat the caps raw.

=Hypholoma candolleanum= Fr., occurs in woods on the ground, or on very rotten wood. It is not so fragile as _H. appendiculatum_ and the gills are dark violaceous, not flesh color as they are in _H. appendiculatum_ when they begin to turn, and nearly free from the stem.

=Hypholoma lacrymabundum= Fr.--This plant was found during September and October in wet grassy places in a shallow ditch by the roadside, and in borders of woods, Ithaca, N. Y., 1898. The plants are scattered or clustered, several often joined at the base of the stem. They are 4--8 cm. high, the cap 2--5 cm. broad, and the stem 4--8 mm. in thickness.

The =pileus= is convex to expanded, sometimes broadly umbonate in age, and usually with radiating wrinkles extending irregularly. On the surface are silky or tomentose threads not much elevated from the surface, and as the plant ages these are drawn into triangular scales which are easily washed apart by the rains. The color is tawny or light yellowish with intermediate shades, darker on the umbo and becoming darker in age, sometimes umber colored, and stained with black, especially after rains where the spores are washed on the pileus. The flesh is tinged with light yellow, or tawny, or brown, soft, and easily broken. The =gills= are sinuate, adnate, somewhat ventricose, very rarely in abnormal specimens anastomosing near the margin of the pileus, at first light yellowish, then shading to umber and spotted with black and rusty brown as the spores mature, easily breaking away from the stipe, whitish on the edge. Drops of moisture sometimes are formed on the gills. =Basidia= abruptly clavate, 30--35 × 10--12 µ. =Cystidia= hyaline, thin walled, projecting above the hymenium 40 µ, and 14--15 µ broad. Spores black, purple tinged, broadly elliptical and somewhat curved, 9--11 × 7--8 µ.

The =stem= is fleshy to fibrous, the same color as the pileus, floccose scaly more or less up to the veil, smooth or white pruinose above the veil, straight or curved, somewhat striate below.

The =veil= in young plants is hairy, of the same texture as the surface of the pileus, torn and mostly clinging to the margin of the pileus, and disappearing with age.

The general habit and different stages of development as well as some of the characters of the plant are shown in Fig. 28 (No. 4620 Cornell University herbarium). The edible qualities of this plant have not been tested.

=Hypholoma rugocephalum= Atkinson.--This interesting species grows in damp places in woods. The plants are tufted or occur singly. They are 8--12 cm. high, the cap 6--10 cm. broad, and the stem 6--10 mm. in thickness.

The =pileus= is convex to expanded, and the margin at last revolute (upturned). The surface is marked by strong wrinkles (rugæ), which radiate irregularly from the center toward the margin. The pileus is broadly umbonate, fleshy at the center and thinner toward the margin, the flesh tinged with yellow, the surface slightly viscid, but not markedly so even when moist, smooth, not hairy or scaly, the thin margin extending little beyond ends of the gills. The color is tawny (near fulvus). The =gills= are adnate, slightly sinuate, 5--7 mm. broad, in age easily breaking away from the stem and then rounded at this end, spotted with the black spores, lighter on the edge. The =spores= are black in mass (with a suggestion of a purple tinge), oval to broadly elliptical, inequilateral, pointed at each end, echinulate, or minutely tuberculate, 8--11 × 6--8 µ. The =basidia= are short, cylindrical; =cystidia= cylindrical, somewhat enlarged at the free end, hyaline, delicate, thin-walled, in groups of two to six or more (perhaps this is partly responsible for the black spotted condition of the gills). The =stem= is cylindrical, even, somewhat bulbous, of the same color as the pileus, but lighter above the annulus, irregular, smooth, fleshy, hollow, continuous with the substance of the pileus. The =annulus= is formed of a few threads, remnants of the veil, which are stained black by the spores. Figure 29 is from plants (No. 3202 C. U. herbarium) collected near Ithaca, July 18, 1899.

STROPHARIA Fr.

The genus _Stropharia_ has purple-brown spores, the gills are attached to the stem, and the veil forms a ring on the stem.

=Stropharia semiglobata= Batsch.--This species is rather common and widely distributed, occurring in grassy places recently manured, or on dung. The plants are scattered or clustered, rarely two or three joined at the base. They are 5--12 cm. high, the cap 1--3 cm. broad, and the stems 2--4 mm. in thickness. The entire plant is light yellow, and viscid when moist, the gills becoming purplish brown, or nearly black. Stevenson says it is regarded as poisonous.

The =pileus= is rounded, then hemispherical (semi-globate), smooth, fleshy at the center, thinner toward the margin, even, very viscid or viscous when moist, light yellow. The =gills= are squarely set against the stem (adnate), broad, smooth, in age purplish brown to blackish, the color more or less clouded. The =spores= in mass, are brownish purple. The =stem= is slender, cylindrical, becoming hollow, straight, even or bulbous below, yellowish, but paler at the apex where there are often parallel striæ, marks from the gills in the young stage. The stem is often viscid and smeared with the glutinous substance which envelopes the plant when young, and from the more or less glutinous veil. The =ring= is glutinous when moist.

Figure 30 is from plants (No. 4613 C. U. herbarium) collected on one of the streets of Ithaca.

=Stropharia stercoraria= Fr., is a closely related plant, about the same size, but the pileus, first hemispherical, then becoming expanded and sometimes striate on the margin, while the stem is stuffed. The gills are said to be of one color and the ring floccose, viscose, and evanescent in drying. It occurs on dung, or in grassy places recently manured.

=Stropharia æruginosa= Curt., the greenish _Stropharia_, is from 6--8 cm. high, and the pileus 5--7 cm. broad. The ground color is yellowish, but the plant is covered with a greenish slime which tends to disappear with age. It is found in woods and open places during late summer and in autumn. According to Stevenson it is poisonous.

FOOTNOTES:

[B] For analytical key to the genera see Chapter XXIV.