I r 
182 The Queensland Naturalist. Vol. I- 
leaves — covered with a very fine, flour-like, grayish- white 
investment, having a slight glistening appearance. By 
aid of the lense we notice innumerable erect bodies spring- 
ing from a close network of delicate fllaments (mycelium). 
These bodies are formed of septate hyphse, terminating 
in oval spores {conidia) that are being continuously formed. 
and shed by abscission. This parasite, that is, in what 
is named its conidia-form conditions, seems to be entirely 
separable from its support and capable of being reinoved 
by simple abrasion. How^ever, the mycelial threads have 
little suckers along their length, and these entering the 
epidermis of the leaf extract nutriment from the cells 
immediately under it. This form of parasitism then is 
a very simple one. 
2. Rust of Acacia {Uromyces fliyllodiorum — Uredi- 
nece). Here we have, also on the leaves of Acacia aulaco- 
carpa, small, rust- brown, raised,. little pustules (<5on), scat- 
tered in ill-defined patches over the surface, that when ex- 
amined by the lens are found to consist of masses of a 
powdery substance, that have welled out from beneath 
the surface, raising and Assuring the epidermis in so doing.. 
This substance is composed of the reproductive organs 
(spores) of the Uromyces fungus, the vegetative portion 
of w^hich does not occur externally, as in the last instance 
of fungus parasitism, but dw'ells internally within the leaf 
tissue without modifying it to any extent, although even- 
tually with the rupture of the epidermis, the subjacent, 
cell-structures change their colour and die,- a reddish dis- 
colouration surrounding * each sorus as evidence of this. 
3. Leaf Brand of Acacia {Diplodia Ikhenopsis— 
Sphceropsidiacece). This parasite occurs on the leaves 
of Acacia complanata, producing symptoms as follows : ■ 
Conspicuous small patches of dead tissue, reddish-brown,, 
wdth raised margins, and that are often confluent, are 
distributed over the surfaces.. Here the fungus ^ growls 
internally in the leaf or is endogenous and soon kills the 
tissue wLere it occurs; the reproductive organs — septate 
elliptical spores — also forming beneath the surface within 
small spherical receptacles {perithecia) deeply immersed 
at flrst — although ultimately apparent as small black 
points, and only tardily liberating their contents. 
4. Leaf Pustule of Eucalyptus {Phyllachora ('I macu-- 
lata, Cke.) — Pyrenomycetece) . This parasite was yielded by 
the large leaves of a young plant of Eucalyptus acmenoides,. 
and w^as brought under our notice by E. Jarvis. Here 
w^ehaveon the living green leaf,- large, low, purplish brown, . 
swollen or raised bodies, measuring J to 1 inch or more 
across, wLose surfaces are densely shagreened with closely- 
set, rounded pustules, the older of which have dark centres... 
Here we have the fungus growing again internally, but. 
