THE INTERNATIONAL ECONOMIC CONGRESS AT VIENNA, 1873. 
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Harriers, 4 species. — Circus. 
Snowy Owl. — Nyctea. 
Eagle Owl. — Bubo. 
It must be admitted that Marenzeller's motion included 
ail the elements necessary to the feasibility of the creation of 
the subject matter of an international Convention, after due 
discussion ; and the President declared that the motion should 
be made the subject of deliberation as laid down by the 
statutes of the Congress. 
A. E. Brehm was of opinion that, schismatically taken, 
it would be found that the decrease in the number of birds 
was not a result of the destruction of nests or of the use of 
bird-lime, nooses and traps. He referred to Gloqer, who in 
one of his writings said that no change could be made in 
the progress of virgin nature, and if, for example, a plague 
of mice should overtake us, this would not be the work of 
nature but of ourselves. But had Gloger seen, as he (Brehm) 
had, how millions upon millions of insect-eating birds (includ- 
ing two species considered noxious) as well as at night the 
bats, make havoc of the masses of locusts that covered 
everything, he would not have maintained his thesis „que 
s'il n'y avait personne, qui ^chenillat les arbres, il n'existerait 
pas de chenilles." 
The cause of the decrease in the numbers of birds is to 
be found in the present system of agriculture. 
In extensive districts we grow vegetation on which insects 
can better subsist and increase; on territory stretching for 
miles we plant certain trees as if we were voluntarily assisting 
the insects, the propagation of which is so large dependent 
upon the same. We cut down every solitary tree, wipe out 
primeval forests without considering that, by so doing, we are 
destroying the homes of birds. We do not like the crow any 
