This section is from the book "Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc.", by George Francis Atkinson. Also available from Amazon: Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc..
Amanita frostiana Pk. Poisonous. - According to Dr. Peck, who published the first description of this plant, it grows in company with Amanita muscaria, but seems to prefer more dense woods, especially mixed or hemlock woods, and occurs from June to October. The plant is 5-8 cm. high, the caps 2-5 cm. broad, and the stems 3-6 mm. in thickness.
The pileus is "convex to expanded, bright orange or yellow, warty, sometimes nearly or quite smooth, striate on the margin; lamellae white or tinged with yellow; stem white or yellowish, stuffed, bearing a slight, sometimes evanescent annulus, bulbous at the base, the bulb slightly margined by the volva; spores globose," 7.5-10 µ in diameter. He notes that it appears like a small form of A. muscaria, to which it was first referred as var. minor, - "The only characters for distinguishing it are its small size and its globose spores." It is near A. muscaria var. puella Pers.
I have several times found this plant in the Adirondack mountains, N. Y., and Ithaca, and also at Blowing Rock, N. C. The volva is often yellowish, so that the warts on the pileus are also yellow, and sometimes the only remnants of the volva on the base of the stem are yellow or orange particles. The annulus is also frequently yellow. In our plants, which seem to be typical, the spores are nearly globose, varying to oval, and with the minute point where the spore was attached to the sterigma at the smaller end, the spores usually being finely granular, 6-9 µ in diameter, and rarely varying towards short elliptical, showing a tendency to approach the shape of the spores of A. muscaria. The species as I have seen it is a very variable one, large forms being difficult to separate from A. muscaria, on the one hand, and others difficult to separate from the depauperate forms of A. caesarea. In the latter, however, the striae are coarser, though the yellow color may be present only on portions of the pileus. The spores of A. caesarea are from globose to oval, ovate or short elliptical, the globose ones often agreeing in size with the spores of A. frostiana, but they usually contain a prominent oil drop or "nucleus," often nearly filling the spore. In some specimens of A. frostiana the spores are quite variable, being nearly globose, ovate to elliptical, approaching the spores of A. muscaria. These intermediate forms should not in themselves lead one to regard all these three species as representing variations in a single variable species. With observations in the field I should think it possible to separate them.
Amanita phalloides Fr. Deadly Poisonous. - The Amanita phalloides and its various forms, or closely related species, are the most dangerous of the poisonous mushrooms. For this reason the A. phalloides is known as the deadly agaric, or deadly amanita. The plant is very variable in color, the forms being pure white, or yellowish, green, or olive to umber. Variations also occur in the way in which the volva ruptures, as well as in the surface characters of the stem, and thus it is often a difficult matter to determine whether all these forms represent a single variable species or whether there are several species, and if so, what are the limits of these species. Whether these are recognized as different forms of one species or as different species, they are all very poisonous. The plant usually occurs in woods or along the borders of woods. It does, however, sometimes occur in lawns. It varies from 6-20 cm. high, the cap from 3-10 cm. broad, and the stem 6-10 mm. in thickness.
The pileus is fleshy, viscid or slimy when moist, smooth, that is, not striate, orbicular to bell-shaped, convex and finally expanded, and in old specimens more or less depressed by the elevation of the margin. The cap is often free from any remnants of the volva, while in other cases portions of the volva or outer veil appear on the surface of the cap in rather broad patches, or it may be broken up into a number of smaller ones quite evenly distributed over the surface of the cap. The presence or absence of these scales on the cap depends entirely on the way in which the volva ruptures. When there is a clean rupture at the apex the pileus is free from scales, but if portions of the apex of the volva are torn away they are apt to remain on the cap.
The white form is common in this country, and so is the olive or umber form. The yellow form is rarer. Sometimes there is only a tinge of yellow at the center of the white pileus, while in other cases a large part of the pileus may be yellow, a deeper shade usually on the center. The green form is probably more common in Europe than in this country. The olive form varies considerably also in the depth of the color, usually darker on the center and fading out to light olive or gray, or whitish, on the margin. In other cases the entire pileus may he dark olive or umber color. The gills in all the forms are white, and free from the stem or only joined by a narrow line. The stem is stuffed when young, but in age is nearly or quite hollow. It is cylindrical, 6-20 cm. long x 6-12 mm. in thickness. In the larger specimens the bulb is quite prominent and abrupt, while in the smaller specimens it is not always proportionally so large. The stem is usually smooth and the color is white, except in the dark forms, when it is dingy or partakes more or less of the color of the pileus, though much lighter in shade. There is a tendency in these forms to a discoloration of the stem where handled or bruised, and this should caution one in comparing such forms with the edible A. albescens.