EFFECT OF SETTLEMENT UPON INDIGENOUS VEGETATION. 233 
list were kindly supplied me by Baron von Mueller from Mr. 
Drummond’s collection. 
It will be noticed that there are several Australian plants in- 
cluded in the alien list. These are plants which through the 
influence of settlement have migrated or been introduced into new 
localities. For instance Paspalum distichum is not a Victorian 
plant, but it has appeared there, how, Ido not know. Sida retusa 
is another of these Australian weeds. It is certainly the com- 
monest weed in Illawarra, but it isa native of the northern parts 
of the Colony, as well as of tropical regions generally. 
Summing up the foregoing, I am of opinion that the chief 
causes of destruction of the native flora are:—(1) The destruction 
of forests for timber, and cultivating the soil, or improving pastures; 
(2) by alteration of surface drainage by the surface being broken, 
either designedly or by cattle ; (3) by the overstocking and feeding 
down of the natural pastures without any means being resorted 
to for renovating them ; and that the destruction or modification 
of the flora by climatic alteration, the checking of bushfires, the 
destruction or modification of native fauna and the introduction 
of a new flora, while they certainly must result in some amount 
of alteration, yet cannot do so great an amount of damage as the 
first group of causes. Further, in the first group the causes 
numbered one and three are to a great extent capable of being 
remedied, as indicated in the body of this paper, while the second 
_of the first group, and all of the second group are almost out of 
our power to alter or modify. 
APPENDIX. 
List of naturalised plants well established and spreading to 
a greater or less extent, with their distribution in the Australian 
Colonies. 
Q. | N. | Vie-| 5 
S. W.|toria.} Aust. 
WwW. 
Tas. | a ust, 
RANUNCULACEX 
fanunculus muricatus, L. ... » | x * 
