TAXONOMY 
279 
constricts off usually four basidiospores. The earth stars differ 
from the puff balls in possessing an outer wall or exoperidium which 
splits in star-shaped fashion. 
Order 2.— Nidulariales, the nest fungi. A group of Gasteromy- 
cetes whose sporophores are crucible- or crater-like. These arise 
from a subterranean mycelium and show 
an outer and inner peridial layer. The 
outer peridium is roughened at its base. 
The inner peridium is leathery and may 
or may not be continued over the top. 
When mature the crucible-like body 
shows black seed-like bodies inside which 
resemble eggs in a bird’s nest. Each 
one of these is connected with the inner 
peridium by a cord which resembles the 
umbilical cord of an animal. These 
inner bodies are called periodiola (sing. 
peridiolum ). Each peridiolum consists 
of a hard glistening outer layer and a 
spongy inner layer surrounding a cavity 
into which basida and basidiospores pro¬ 
ject. These fungi are found in stiff 
clayey soil. 
Order 3.— Phallales, the carrion or 
stink-horn fungi. This, the highest 
group of the Autobasidiomycetes, con¬ 
sists of highly and characteristically 
colored forms which, when mature, emit 
most vile and penetrating odors. The 
fruiting body, in each instance, begins 
as an egg-shaped structure which starts 
its growth from a widely spread under¬ 
ground mycelium of chalky-white color. 
As the “eggs” enlarge they push above the surface of the ground. 
The central portion, elongating, then breaks through the outer or 
peridial portion, which remains as a cup or volva at the base of the 
mature fruit body. Upon the summit of the central stalk rests the 
Pig. 148. —Mature stink- 
horn, Dictyophora duplicata. 
( Harshberger, front photo, by 
W. H. Walmsley.) 
