cooper’s hawk. 
5 
necessity of employing* numerous subdivisions, not only 
in this, but also in its allied genus Strix. These, however, 
we cannot agree to admit as genera, preferring to call 
them subgenera, and giving them a name, but when 
having occasion to mention a species belonging to any 
of them, to employ the name of the great genus. 
The desire of avoiding too great a multiplication of 
groups, has caused some, even of the first ornithologists 
of our time, to employ sections that are not natural, 
and with false or inapplicable characters, and, as if they 
would compel nature to conform to their preconceived 
and narrow views, after having assigned decided limits 
to their groups, to force into them species not only 
widely different, but that do not even possess the 
artificial character proposed. We shall not imitate this 
irrational example. It shall rather be our object to 
compose natural groups, and, in obedience to this 
principle, whenever we meet with a group, or even a 
single species, clearly insulated, it shall at least be 
pointed out, not so much regarding the number of our 
subgenera, as the characters that unite the species of 
which they are respectively composed. 
It is objected to the numerous subdivisions that have 
been proposed in our day, that they pass into and blend 
insensibly with each other. This is no doubt true ; 
but is it not the same with regard to natural groups of 
every denomination ? It is this fact which has induced 
us to consider them as subgenera, and not as distinct 
genera. We are told, however, by the advocates for 
numerous genera, that, in giving a name, we adopt a 
genus, but we do not see that this necessarily follows. 
There are, we confess, other grounds on which we 
might be attacked with more advantage. We may, 
perhaps, be charged with inconsistency in refusing to 
admit, as the foundation of generic groups in the 
Mapaces, characters which are allowed, not only by 
ourselves, but by some of those who are most strenuously 
opposed to the multiplication of genera, to have quite 
sufficient importance for such distinction in other 
families. With what propriety, it might be asked, x can 
