94 
EVOLUTION OF PLANTS 
spore-fruit, which may have a definite character, as in 
the mushroom, where the “gills” (Fig. 25, A, g) are 
of 
ne 
this nature. The spores on germination form a 
w mycelium, which in time produces spore-fruits. 
Fic. 25 (Basidiomycetes). — A, acluster of spore-fruits of the common mush- 
room, arising non-sexually from the mycelium, m, which is buried in 
the ground; B, a very young mushroom; C, a section of an older one 
showing the gills, g, upon which the spores are borne; D, diagram 
showing a section of a gill with the spore-bearing “‘ basidia,’’ 6, cover- 
ing its surface; E, I, young, 11, mature basidium of a toadstool (Co- 
prinus), showing the spores borne at the summit; F, spore-fruit of Tre- 
mella, one of the lower Basidiomycetes; the spores cover the whole 
surface of the irregular spore-fruit ; G, a bird’s-nest fungus (Cyathus) : 
the spores are borne inside the “‘ sporangia,” sp, within the cup; H, 
earth-star (Geaster), one of the Gasteromycetes allied to the puff-balls. 
(Figs. A, B, after Warming; C, after Atkinson.) 
The lowest of the Basidiomycetes show analogies 
with the rusts (Acidiomycetes), and do not have the 
basidia restricted to any definite part of the spore-fruit, 
but they may be produced all over it, as in the soft 
gelatinous Tremella (Fig. 25, F), whose convoluted 
soft yellow or orange masses are not uncommon on 
