7 
destruction of the small Rumex-Sorrel (Rumex Acetosella, L.) can 
be aided by sowing broadcast repeatedly turnips between, and 
feeding off through sheep the united young growth, the sorrel as 
the weaker plant getting suffocated and tramped out. Pigs will 
•devour as well Thistle-roots as Bracken-roots, and by keeping the 
animals within hurdles, moved gradually over the ground, the 
annihilation of these plants can be effected more readily on some 
places than by other means. It should be further taken into 
consideration, that in the winterless clime of our lowlands the 
growth of weeds proceeds more or less through the whole year, 
and this renders coping with such plants here far more onerous 
than in countries where the length and severity of the winters 
annihilate largely such plants and their seeds. Therefore, the 
Australian ruralist has far more perseveringly to bring his 
operations to bear for the suppression even of mere annuals. To 
deal with obtrusive plants of perennial growth is, of course, still 
far more complicated, as our experiences show with such plants, 
for instance, as the Sorrel-Rumex, the Bracken-Fern, the Furze, 
the Briar-Rose. Hitherto the Thistle and cognate plants which 
have invaded our colony are all annuals, except Carduus arvensis, 
above alluded to. This can further be distinguished from the 
other Thistles, with us hitherto naturalized, by perfect male 
and perfect female flowers being developed by separate individual 
plants only. Carduus arvensis is a “ Plume-Thistle,” that is to 
say, the tuft on the summit of the seed-like fruits consists of 
plumous bristlets. As yet only one more real Plume Thistle is 
widely naturalized in our colony, the very common Carduus 
lanceolatus, the other remaining genuine Carduus, namely C. 
pycnocephalus, has simply hair-like bristlets of the tuft. These 
easy distinctions as regards the “ pappus ” are observable already 
in the young flower-lieadlets. 
For further facilitating the use of the plates and the descriptions 
of the nine plants recorded here, it may introductorily be noted 
that the Heraldic Scotch or Onopordon-Thistle, which in its less 
grey state bears some resemblance to Carduus lanceolatus, has 
the inside bottom of the flower-lieadlets, so to say, honeycombed, 
and not beset with capillulary bristlets; while the Spotted Thistle, 
Carduus Marianus, is known well enough everywhere by the 
vernacular name, signifying as if a milky fluid had been sprinkled 
on the foliage. The Centaureas are spurious Thistles; and as we 
have hitherto to attend only to two, their discrimination is quite 
easy by the mere colour of the flowers, purple in Centaurea Calci- 
trapa, yellow in Centaurea Melitensis. The only other yellow- 
flowering plant coming under notice on this occasion is the very 
conspicuous Saffron-Thistle, K entrophy llum lanatum. Thus it 
solely remains under the Thistle Act to recognise the so-called 
Bathurst- Burr, a plant very different from the eight others treated 
in this essay, and so distinct that it in no way can be called a 
real Thistle. 
