392 
THALLOPHY TES 
organic matter in the ground. The sporophore is at first globose, 
but the gleba soon breaks out of the peridium and is elevated to 
some distance above ground by an elongating stalk. The spore 
Fic. 348.—A_ Bird’s 
Nest Fungus, Nidularia. 
About natural size. 
masses are slimy and have the odor of 
carrion. Certain insects which dissemi- 
nate the spores are attracted by the 
odor. 
Smuts (Ustilaginales). — The Smuts 
are parasitic Basidiomycetes. In some 
Smuts, the mycelium, although evident 
only in local areas, traverses widely 
through the host, while in others only 
local areas of the host are attacked. 
No sporophores, such as characterize 
the Toadstools and Puffballs, occur in the Smuts. There are 
more than 2000 species of Smuts. They attack chiefly plants 
of the Grass family and espe- 
cially the cereals, the grains of 
which they commonly displace 
with powdery black masses of 
spores. The financial loss due 
to Oat Smut alone has been 
estimated to be $10,000,000 
annually in the United States. 
In addition to the loss due to 
the destruction of the cereal 
crops and the lowering of their 
market price, there is consider- 
able loss due to Smut explosions 
in thrashing machines. During 
the summer of 1914, 300 thrash- 
ing machines were blown up or 
burned in the Pacific Northwest 
by Smut explosions. Smut dust 
is highly combustible when dry, 
and is probably ignited by static 
electricity in the cylinder of the 
Fic. 349. — Stink Horn Fungus, 
Phallus impudicus. At the right, 
vertical section of the Fungus in 
early stage of development, showing 
the gleba enclosed by the peridium. 
At the left, mature stage, showmg 
the gleba elevated much above the 
peridium. X 3. 
thrashing machine. The Smuts are particularly destructive 
to Oats, Wheat, Rye, and Barley. Corn Smut is exceedingly 
common but less destructive. 
