140 THE STRUGGLE FOR LIFE. 
had fair play among themselves, and so kept the balance true; 
introduce some new factor and everything is deranged— 
destroy the insectivorous birds, and the crops are at once 
ravaged by insects. In this country, for quite two hundred 
years, the law compelled the overseers to pay for the destruc- 
tion of rooks and similar birds and of their eggs. The farmer 
grudged the toll taken of his grain, and did not understand 
that it was but a small price to pay for ridding his fields of 
the destructive wireworm. 
Time will only allow me to quote one instance of the results 
of the interference of man when he introduces a species into 
a country without Nature’s checks. It is that of the intro- 
duction of the rabbit into Australia ; the climate there suits 
them perfectly, and they are practically exempt from the 
attacks of foxes, dogs, stoats, weasels, and the like. The 
results have been that they have in thousands and thousands 
of square miles, in fertile pasture land, destroyed the sheep. 
To show the extreme rapidity with which they can multiply 
I may quote one case. About the year 1867, a Mr. Robinson 
turned thirteen wild rabbits out on his run, and by 1870, he 
had spent £7,000 in the vain endeavour to get rid of them. 
Both Government and private individuals have to face a 
heavy annual expense in order to keep them under in any 
way. 
It is clearly impossible that all the individual members of 
a given generation can, under ordinary circumstances, reach 
maturity. Now what determines the success of any individ- 
ual germ? Darwin has proved to demonstration that it is 
no matter of blind chance, but that certain individuals of the 
generation start with the dice loaded in their favour. Time 
will not permit me even to glance at the different lines of in- 
vestigation which, when followed, will lead to the same result; 
but I think that a very few words will be sufficient to show 
that in this respect, as in all others, the Universe is under 
the ‘“‘ Reign of Law.” 
