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PHARMACEUTICAL BOTANY 
attached to the stipe. This constitutes the annulus or ring (true 
annulus). The hyphae in the pileus form the Tela contexta. If we 
make a section through a gill, the hyphae are seen to run longitudi- 
nally. The central part is called the trama; next and outside trama 
is the sub-hymenium; next, hymenium, consisting of basidia (hence a 
basidial layer). Each basidium bears one or two little points known 
as sterigmata. Each sterigma bears a purplish-brown basidiospore. 
The basidiospores falling to the ground germinate into hyphse and 
these become interlaced to form a mycelium. 
Fig. ioo. — Meadow mushroom ( Agaricus campestris L.). A, view showing 
under side of pileus; g, gills; a, annulus, or remains of the veil attached to the 
stipe; B, side view; s, stipe; a, annulus; p, margin of pileus, showing at intervals 
the remains of the veil. (Gager, after W. A. Murrill.) 
In the wild mushroom the gills are at first pink, in cultivated, 
fawn-colored. Ultimately in wild form the gills turn brownish. 
The spores are purplish-brown. The color of the stipe and upper 
surface of the pileus varies from whitish to a drab color. 
The Amanitas (Poisonous Fungi). — Amanita muscaria and Amanita 
phalloides, commonly known as the “fly agaric” and the “deadly 
agaric” respectively, are very poisonous forms. Amanita muscaria 
is common in coniferous forests, although may occasionally be found 
