Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 63. (Budapest 1971)
Bohus, G.: Agaricus studies III.
ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 63. PARS BOTANICA 1971. Agaricus Studies III. By G. BOHUS, Budapest The Vaporarius-group Agarieus elvensis sensu CKE., BOTTD., non 13. et BR. The species was collected on some occasions in England and France in the last quarter of the nineteenth and the first one of the twentieth centuries. It was not recorded in recent literature, save as an occasional synonym. Thus MOELLER (1951) considered it a drought form of A. vaporarius; DENNIS, ORTON and HOEA (I960) equalled it with A. vaporarius, whereas LEBEDJEVA (1949) believed it to be a synonym of A. augustus. In my experience, however, it is a well distinguishable species, one of the easily identifiable Agaricus taxa. Its cespitose appearance, similar to that of Collybia fusipes, at other times to Cortinarius damascenus, and the special form of the stem, are rather unusual characteristics in the genus Agaricus. A brief description was given by COOKE (1883), a more detailed one by BOUDIER (1905 — 1910) and REA (1922). The description given below was made on the basis of a rich material of about 50 fruit bodies. Fruit body at first covered with a universal veil, brown on the pileus and white on the stem. Pileus subglobose, semiglobate, then expanded; fleshy; 8—18 cm.; young brown and smooth; pellicle soon breaking up on a brown or brownish white ground into nice, fibrillose and pointed brown squames, medially into squamules, as on BOTTDIER'S (1905—1910) Figure 134. Gills free; 4—8 mm. broad; at first whitish, then dirty rosa, finally blackish brown; reddening when cut young. Stem cespitose (on one occasion in a fascicle of 27 fruit bodies); attenuated towards base or with a taproot or swollen in middle and attenuated at base; rarely branching; 8—18 cm. long, 12—50 mm. thick; fistulöse or not; when young whitish or dirty whitish, soon, or when touched, turning brown or more rarely reddish brown; above ring a bit fibrillose, below with one or two zones as rudimentary rings, or with veilsquames or fibrils. Ring double: upper layer thin, whitish, young vividly turning red when touched, sheathed above; lower layer felty, thick, soon brownish, peronate, dentate at edge or broken here and there or breaking up into fibrils. Young flesh in pileum whitish, in stem brownish; when cut turning here and there vinaceousred, then, or without reddening, rapidly turning brownish; firm; chemical reactions: with strong nitric acid immediately red then rapidly yellow; with ammonia, sodium hydroxide, Lugol and Schäffer reagents negative; with phenolaniline, guaiacol and pyramidon solutions positive. Young specimens during drying turning here and there —especially on upper layer of ring —orange-red. Smell pleasant. Edible. Young specimens tasty, older ones tarty when cooked. Spores roundish ovate: 6.0—6.5x4.2—5.4 p.. Basidia 4-spored; clavate: 19—23x X6 —7—(8) p.. Marginal cystidia clavate or cylindrical: 21—35x6".5—8 p..
