i88s-] 
Acclimatisation. 
207 
particular arrangement, adapted to the soil, the climate, and 
all other circumstances of that locality. Hence it was sup- 
posed that, if transplanted to any other country, they would 
be less prosperous than at home, and that, conversely, 
species brought from elsewhere would maintain their ground 
with difficulty, if at all. 
Ibis docftrine, it may be remarked, involves almost of 
necessity the theory of a plurality of centres of mechanical 
creation, or otherwise a series of elective migrations and 
tiansformations which in their outcome approach very nearly 
to Evolution. 
I here are, indeed, many cases where the plants and ani- 
mals of one country — the former more especially — seem 
limited to their original locality. Thus the durian and the 
mangosteen of the Malay Islands utterly fail in the West 
Indies, and the shaddocks of the Azores and the Antilles 
are ,£ flavourless as turnips if compared with those of 
Bangkok or Labuan.” 
But there are no less signal instances to the contrary. 
1 he thistle brought from Scotland to Australia grows there 
with a luxuriance quite unknown in its native soil. Even 
the sweet-brier — which is nowhere exceedingly common or 
rampant in Britain— is becoming in New South Wales a 
serious nuisance which the farmer and the gardener are 
obliged a< 5 tively to combat. 
Nor are these exceptional cases even among plants. With 
animals there is still less difficulty. The rat multiplies in 
every corner of the globe where it has penetrated no less 
readily than in its original home on the Wolga. The rabbit, 
foolishly — or I might say criminally — turned loose in Aus- 
tralia has proved itself an almost unlimited curse. The 
sparrow, acclimatised in the United States, in Australia, and 
in New Zealand, contrary to the advice of judicious 
European naturalists, has not only established itself, but is 
seriously interfering with the original bird-population. 
Descending lower in the scale — if I may so say— of animal 
life, it is certain that the cockroach, or “ black beetle ” of 
unscientific insedl-lore, is not indigenous in Britain. It is 
no less certain that its extirpation is about as unlikely as 
the conversion of the Anti-Vivisedtionists to common sense 
and common honesty. Blood-sucking gnats, according to 
Baron Osten-vSacken, were only introduced into the Sand- 
wich Islands about 1828 to 1830 : they have since spread, 
and are becoming a serious nuisance. The same eminent 
authority states (“ Trans. Entom. Soc. of London,” 1884, 
p. 492) that the two-winged insebts popularly “ lumped ” 
