Some Colorado Mushrooms 
7 
surface of the soil, the mass of leaves or other decaying vegetation, 
or upon the surface if it is a decaying log or stump. These little 
bodies rapidly increase in size until they are prepared to expand 
into the mature mushroom. In some species of fleshy fungi this 
last stage of growth is very rapid so that these plants appear to 
spring up in a night, while in others it requires several days for 
the complete unfolding of the fruiting part. 
SPORES. 
During this period of expanding to full size, the mushroom 
is also maturing an abundance of spores. Spores are the minute 
bodies by means of which the fungus is able to start a new genera¬ 
tion elsewhere or to reproduce itself. They are so small that in 
some fungi a compact mass of spores as large as the head of a par¬ 
lor match could contain as many as ten millions of these micro¬ 
scopic bodies, enough to cover an acre and a half at the rate of one 
spore to each square inch of surface. Their minute size enables 
Fig. 3. 
Fig. 4. 
No. 3. Fungous spores showing a variety of shapes as found in dif¬ 
ferent kinds of fungi. Highly magnified. 
No. 4. Spores of the common mushroom germinating. Each one is 
sending out a thin-walled tube which is the beginning of the network of 
mycelium of the fungus. Highly magnified. 
them to float readily in the air like the finest particles of dust and 
it is only when large numbers of them are thrown into the air at 
one time, as from a mature puff ball, that we are able to see them 
as a miniature cloud of smoke. The enormous number of spores 
which even one mushroom may shed readily accounts for the ease 
with which these plants find every suitable place in which to grow. 
When the spores of fungi fall into a suitable condition of mois¬ 
ture and heat and with the proper food supply at hand, they may 
germinate by sending out a slender germ tube. This germ tube 
begins at once to gather nourishment from the material suited to 
its growth and in this way a new colony of the fungus is soon estab¬ 
lished. Frequently a period of drought may set in after the myce- 
