JO 
THE LARGER FUNGI 
is relatively simple, find they form no large and obvious fruiting bodies. More- 
over, we will not consider the microscopic, fungi that play such a part in injuring 
plants of economic importance to man. This group falls to the lot of the plant 
pathologist. The majority of these fungi are microscopic in themselves, though 
the reactions in the host-plant’s tissues to which they give rise may be quite 
large and striking in appearance. The rusty galls on many of our acacias due 
to species of Vromycladium are an example in point. In some cases, indeed, 
the fungus itself may form a body obvious to the naked eye and of a definite 
shape, as is the case with the sclerotium of ergot found on one at least of our 
native grasses. However, as a rule there does not occur amongst these plant 
pests any fungous forms that suggest at all closely a. “toadstool,” a mushroom, 
a bracket fungus, a eoral-or jelly-fungus, or a puffball. The majority of the 
diseases of plants, shown by wilting, spots on leaves, pustules, die backs, warty 
or distoi'ted growths and galls, when not due to insects or mites, are caused by 
fungi not closely related to the larger forms with which we are concerned. 
Occasionally such a disease, as for instance silver-leaf of plums, is due to the 
mycelium of one of these huger forms, though the fruiting of the fungus is 
rarely seen. However, such fungi as the rusts, though more or less microscopic, 
are not so distantly related to the toadstools as one might think. Moreover, we 
find that many of the fungi studied by the plant pathologist have their spores 
contained in special sacs called asei and these correspond with similar structures 
found in some large fleshy, and in some cases edible, fungi (such as MorcheVa) 
with which we shall deal. 
The fungi which live in intimate association with the roots of epiphytic orchids 
in tropical forests also do not come within the purview of tills Handbook. These 
fungi, living thus in symbiosis with the cells of these higher plants, are 
probably of material service lo the orchitis and would seem to lie essential for 
the development of their seeds. 
'The lichens constitute a curious class of plants inasmuch as each species is of 
composite origin, being the result of the intimate living together of a species 
of alga with a fungus species, the result being a structure entirely different 
in appearance from what would be seen were tho alga and the fungus each 
loading an independent existence. The lichens also arc outside our scope. 
With what then do we propose to deal? It is with a large group that in the 
fruiting condition exhibit obvious fleshy, leathery, woody, or jelly-like structures 
of a form and coloring peculiar to each particular species. Nearly all these forms 
are. classifiable under one division of the fungi known ns the Basidiomycetes, tho 
structure of which indicates that the plants concerned are amongst the most highly 
developed or complex of the fungi taken as a whole. In addition, we shall include 
also a few genera that show somewhat similar conspicuous more or less fleshy 
fruiting bodies, but which have their spores contained in sacs (asei), each sac 
possessing eight spores. This latter great division of the fungi is, in consequence, 
known as the Axcomyivtrx, and it is to be noted, as already stated, that some of 
the microscopic species of this division play a prominent part in the causation of 
plant diseases. We will not deal with these small forms or with a number of 
more or less saucer-shaped species amongst the Dtieomyectefi, which also have 
their spores in asei. These latter, varying in size from less than a threepenny 
piece to that of I m I f a crown or more, might quite well be included in out 
category, but no thorough attempt has as yet been made to work out the South 
Australian species. 
From the point of view of this Handbook, then, the “larger fungi ' 1 embrace 
all the BaMdiomyceles, even though some may be not much larger than a pin’s 
head, together with a few of the most highly developed Ai<coniycetes that have 
prominent fleslxv fruiting bodies. As already stated, the Ascomyaetes are 
characterised by having the spores — or at least certain spores — contained at one 
time within definite little sacs. In the Basbdiomycetes, the spores are not developed 
in sacs, but are borne at the end of certain fungous hyphae, known as basidia, 
usually projecting from tho basidium on tne ends of delicate processes known as 
sterigmata. Each basidium usually support's four spores. The gills of a common 
mushroom possess numerous basidia with their free ends projecting from amongst 
the other hyphae, and on each basidium will be seen four sterigmata capped each 
with a spore. In this way the spores are raised from the surface on which they 
have developed so that when mature they can fall free from the gills and bo 
distributed around by currents of air. 
