994 FUNGI, 
are accompanied by fungi, which either completely destroy the 
tissue, or alter its nature so much by the abstraction of the 
cellulose and lignine, that it becomes loose and friable. Thus 
fungi induce the rapid destruction of decaying wood. These 
are the conclusions determined by Schacht, in his memoir on 
the subject.* 
We may allude, in passing, to another phase of destructive- 
ness in the mycelium of fungi, which traverse the soil and in- 
terfere most injuriously with the growth of shrubs and trees. 
The reader of journals devoted to horticulture will not fail to 
notice the constant appeals for advice to stop the work of fungi 
in the soil, which sometimes threatens vines, at others conifers, 
and at others rhododendrons. Dead leaves, and other vegetable 
substances, not thoroughly and completely decayed, are almost 
sure to introduce this unwelcome element. 
Living plants suffer considerably from the predations of para- 
sitic specics, and foremost amongst these in importance are 
those which attack the cereals. The corn mildew and its accom- 
panying rust are cosmopolitan, as far as we know, wherever 
corn is cultivated, whether in Australia or on the slopes of the 
Himalayas. The same may also be said of smut, for Ustilago is 
as common in Asia and America as in Europe. We have seen it 
on numerous grasses as well as on barley from the Punjab, and 
a species different from Ustilago maydis on the male florets of 
maize from the same locality. In addition to this, we learn 
that in 1870 one form made its appearance on rice. It was 
described as constituting in some of the infested grains a 
whitish, gummy, interlaced, ill-defined, thread-like mycelium, 
growing at the expense of the tissues of the affected organs, 
and at last becoming converted into a more cr less coherent 
mass of spores, of a dirty green colour, on the exterior of the 
deformed grains. Beneath the outer coating the aggregated 
spores are of a bright orange red ; the central portion has a vesi- 
cular appearance, and is white in colour.t It is difficult to 
* Schacht, ‘‘ Fungous Threads in the Cells of Plants,” in Pringsheim's ‘‘ Jahr- 
buch.” Berlin, 1863. 
+ ‘ Proceedings of the Agri. Hort. Soc. of India” (1871), p. 85. 
