THE Stupy oF Birp LIFE. 155 
can be identified by these notes at a considerable distance, and 
thus much time is saved when all we want to know about it at 
the particular time is whether it is such and such a locality 
or not. 
I may, perhaps, again be allowed to digress a little and to 
say that great attention also ought to be paid to the flight of 
birds—another difficult matter, and one requiring much time— 
for by a good knowledge of this the lolloping flight of the Green 
Woodpecker in the distance would serve to distinguish it for 
certain from any other bird, whilst the quick hurried flight of the 
Starling, the dipping flight of the Wagtails, the measured flapping 
of the Rook, the quicker one of the Jackdaw, the zig-zag flight 
of the Snipe, and so on, would tell you at once what each 
bird was. 
I may mention also the difficulties connected with oology 
and caliology, but they are too many and too intricate, and too 
much beyond the scope of my personal knowledge in their higher 
details for me to do more than mention them. 
In concluding this part I cannot help alluding also to 
another difficulty in ornithology which needs a great amount of 
attention, labour, and observation, and which is one that has, as 
it seems to me, been somewhat neglected. It is that of the 
pairing of birds. It will be sufficient to say here in this limited 
paper that all birds can be divided into three classes with respect 
to this. Those which pair for life, those which pair each year, 
and those which never pair, but are polygamous. It will be 
easily seen that there is plenty of room for close observation 
here. I have no intention of attempting to shew how the classes 
can be separated. ‘There is certainly a broad general rule, but 
all I have to do to-night is to call attention to a very interesting 
difficulty with the purpose of giving some idea of another of the 
many difficulties of the ornithologist in his study of bird life, 
and to shew what an amount of delightful work the field 
ornithologist has which the cabinet ornithologist has not and 
never can have till he comes out into the open. 
The final difficulty with which I have space to deal is that 
the ornithologist finds it very difficult to get anyone in his 
Vicinity to appreciate his labours. Everyone, if he confesses the 
truth, likes to have his labours appreciated and likes to find that 
someone takes an interest in his work and its results. The dis- 
