ANALOGIES OP THE FALCONIDJE. 
293 
the subtypical group of the Falconidce. Their mutual 
analogy, therefore, would be substantiated upon this 
ground only, setting aside the considerations we have 
just stated as corroborating their juxtaposition in the 
above table. We have expressly stated, in our develop- 
ment of the theory of variation, that, in all natural 
groups, it is much more difficult to discover the analo- 
gies of the typical and subtypical divisions than those 
of the three aberrant ones : the simple reason for which 
is this, that where two or more circles are brought into 
comparison, the two typical divisions of each, from being 
the most dissimilar and widest apart, will, of course, be 
the most difficult to assimilate by characters or habits 
common to each. But let us now proceed to the aber- 
rant division, including the buzzards, the kites, and the 
eagles. These will verify the above opinion, for their 
analogies lie open to every well-informed ornithologist, 
although they have never yet been stated. The chief 
distinction, then, of the buzzards (Buteo) is their great 
extent of wing, which enables them to skim along just 
above the surface of the ground, in search of their food, 
instead of watching for its appearance, like other hawks, 
when resting. But, as the establishment of this fact is 
of the first importance to our present purpose, let us 
hear the account which ]>r. Richardson has given of the 
American henharrier, a typical bird of this genus : — 
“ This bird takes its prey from the ground, hunts long 
and dilig ently for it on the wing, and quarters the dis- 
trict regularly, so as to survey every spot, wheeling 
backwards and forwards in easy graceful circles, with 
little seeming effort or flapping of the wings. It is 
wary, but not timid; avoiding the sportsman, but not 
easily driven away from its hunting grounds. It is a 
common species on the plains of the Saskatchewan, 
seldom less than five or six being in sight at a time, 
but each keeping to a particular beat until it has com- 
pletely examined it." Wilson, again, observes of an- 
other species of this group, the Butco lagopus, or rough- 
legged buzzard, that it has the habit of coursing over 
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