GENERAL DESCRIPTION 383 
plants. Even the saprophytic forms cause some undesirable 
destruction. They often start in the wounds of fruit trees, shade 
trees, and forest trees, and the action of their mycelia hastens 
decay and may lead to the destruction of the tree. 
In many forms the mycelium, after it is well established in the 
region of food supply, produces on the surface of the substratum 
some kind of a body in which the spores are borne. It will be 
recalled that this is the habit of the Morel. This body, since it 
bears the spore, is called a sporophore which really means a 
“spore-bearing body.” It is a term commonly applied to a 
spore-bearing hyphae or to any portion or all of the plant body 
which has to do with bearing spores. Thus the wrinkled top and 
stalk bearing it constitutes the sporophore in the Morel. In the 
Toadstools and Mushrooms, the sporophore is often umbrella- 
shaped. In some forms which grow on the sides of trees and 
stumps, the sporophore resembles a small shelf projecting from 
the support, and in this case the sporophore is often hard. In 
Puffballs the sporophore is more or less globular. Sporophores 
are extremely variable in both shape and texture, and are the 
structures by which those Fungi which have them are classified. 
The sporophore is the part of the Fungus that attracts attention. 
It is the portion that is eaten and called a Mushroom. The 
portion of the mycelium which traverses the substratum is usually 
hidden, and its presence is not known until the sporophore 
appears. 
Many of the parasitic Basidiomycetes, like the Smuts and 
Rusts, have no conspicuous sporophores, and the presence of the 
mycelium is indicated only by the occurrence of unusual struc- 
tures on the surface of the host plant. In case of Smut the pres- 
ence of the disease is indicated by the appearance of Smut balls, 
and in Rusts, by the red or black blisters occurring on the leaves 
and stem of the host. 
Although the basidiospores are the characteristic spores of the 
group, a number of other kinds of spores occur, which in some 
cases are more important in reproduction than the basidiospores. 
Sexual reproduction has been entirely lost by many of the group, 
and in those where it is retained the fusion is between hyphae, 
there being no sex organs formed. There are no odspores or 
zygospores to be considered in this group. 
The Basidiomycetes, of which there are 14,000 or more species, 
