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..
This lepiota resembles A. asper in some respects, but it is smaller and the spores are much smaller, being very minute. The plant is 5-8 cm. high, the pileus 2-4 cm. broad, and the stem 4-6 mm. in thickness. It grows in leaf mould in the woods and has been found at Ithaca, N. Y., twice during July and September, 1897.
The pileus is convex and bell-shaped, becoming nearly or quite expanded. It is hair brown to olive brown in color. The surface is dry, made up of interwoven threads, and is adorned with numerous small, erect, pointed scales resembling in this respect A. asper Fr. The gills are white or yellowish, free, but rather close to the stem, narrow, often eroded on the edge, sometimes forked near the stem, and some of them arranged in pairs. The spores are oblong, smooth, and very minute, measuring 5 x 2 µ. The stem is the same color as the pileus, cylindrical, hollow, with loose threads in the cavity, enlarged into a rounded bulb below, minutely downy to pubescent. The outer portion of the bulb is formed of intricately interwoven threads, among which are entangled soil and humus particles. The veil is white, silky, hairy, separating from the stem like a dense cor-tina, the threads stretched both above and below as shown in Fig. 84 from plants (No. 3157 C. U. herbarium), collected at Ithaca.
In some specimens, as the pileus expands, the spaces between the pointed scales are torn, thus forming quite coarse scales which are often arranged in more or less concentric rows, showing the yellow-tinged flesh in the cracks, and the coarse scales bearing the tine point at the center. A layer connecting the margin of the pileus with the base of the stem and covered with fine brown points, sometimes separates from the edge of the cap and the base of the stem, and clings partly to the cortina and partly to the stem in much the same way that portions of the volva cling to the stem of certain species of Amanita, as seen in A. velatipes (Fig. 66). Sometimes this is left on the base of the stem and then resembles a short, free limb of a volva, and suggests a species of Amanita. The scales, however, are concrete with the pileus, and the species appears to show a closer relationship with Lepiota.
Plate 26, Figure 84
Lepiota asperula. Cap hair-brown to olive-brown, scales minute, pointed; gills and stem white (natural size). Copyright.