FUNGI. 317 
The mushroom may be regarded as an ideal 
fungus of the highest type ; and consequently the 
preceding description is only applicable to the 
class which it represents. There are varieties of 
structure as there are varieties of form. There are 
six large orders of fungi in which the organs 
of fructification are widely different. The first 
order is called Hymenomycetes, or naked fungi, 
because the seed-bearing organs are naked, or 
placed externally. This is the largest, most 
important, and most highly developed order. 
The mushroom, toadstool, chantarelle, amadou, 
are familiar examples of it. The hymenium 
assumes various shapes in the different genera. 
In the mushroom it forms gills, in the toad- 
stool tubes, in the chantarelle veins, in the 
amadou pores, and in the hydnum spines. The 
second order, called Gasteromycetes, has the seed- 
bearing organs enclosed in a membranous cover- 
ing, like the stomach of an animal, whence 
the name. The stinkhorn, the Melanogaster 
or red truffle of Bath, the bird’s-nest fungus, 
and the puff-ball, are familiar examples of this 
order. Some of the forms, such as Stemonitis 
fusca (Fig. 31), common on rotten wood, are ex- 
ceedingly elegant. The third order is called Cozzo- 
mycetes or dust-fungi, because the spore-cases are 
produced beneath the epidermis of plants, or the 
