10 
GENERALIA 
These circumstances render it imperative that we should, 
before all, define birds and their significance in respect to 
nature and human society; for herein lies the true vocation 
and importance of the International Convention; hereby only 
can v^e form a proper conception of the same; and hereon 
depends the possibility of furthering an adequate development 
of the cause. 
It is not a question of treating birds from a systematic 
point of view, i. e. from the point of view of descriptive 
natural history, in the common acceptation of the word; we 
must collect and employ all the biological observations (as 
well as the conclusions to be drawn therefrom) which science 
has amassed side by side with systematic formulae, and 
which, from the point of view of both nature and society, 
justify protection or the opposite. In a word we must treat 
of the importance or significance of birds in the household 
both of Nature and of Man. 
The characterisation of birds from this point of view may 
be briefly summed up as follows. 
Without taking into consideration those genera of birds 
— such as the Ostrich family, the Kivi (Apteryx) etc. — which, 
though still extant, are the representatives of decadence, — 
their peculiar characteristic being that they are not flyers 
and are consequently limited as to the power of changing 
their abode, which is, in general, considered, to be an essential 
feature of a „bird*, — we intend to deal with those birds 
the organic structure of which includes, besides the power 
of flight, i. e. ability to change their abode, a tooMike, if 
we may call it so, and very multiform system of external 
organs. These properties, taken collectively, produce the 
extensive and intensive influence which may be summed 
up as the search of birds for their food. 
The means of changing the haunts is the wing, which is 
