BIRDS AND MAN 
23 
And that it is high time that the affair should be settled, 
is evident to everyone who is acquainted with the facts. 
The phenomenon that species of birds which have from 
time immemorial built their nests at certain points of certain 
districts are disappearing, is becoming daily more frequent: 
so also is the phenomenon that particularly birds of passage 
that pass in spring never return, though the natural conditions 
of the respective points have undergone no essential change. 
The only natural explanation of this phenomenon is that the species 
of birds, flocking together, fall at once and without exception 
into the nets of the tribe inhabiting the particular district 
over which they pass, such tribe being ornithophage. 
This fact seems to be proved by the Italian bird-markets, 
where particular species are generally on sale in large quan- 
tities simultaneously, a sign of their having come from the 
same region and of having been caught in masses at the 
same spot. 
This fact alone justifies the question being treated as an 
international one; for the nests of these unfortunate victims 
were not on Italian soil. A further justification is afforded 
by the fact that the ordinary movement of birds takes place 
between the Northern Polar Regions and the Equator, thus 
touching practically every State. 
