cooper’s hawk. 
9 
its adult state as Falco Pennsylvanicus , and in its youth 
as Falco velox y was established on the sparrow hawk of 
Europe, Falco nisus , but the American species just 
mentioned are no less typical. The hawks of this 
section are more elegantly shaped, being much more 
slender ; their wings are still shorter than in the other 
section, reaching little beyond the origin of the tail, 
and their tarsi slender and elongated, with a smooth 
and almost continuous covering. 
Notwithstanding their smaller size and diminished 
strength, their superior courage and audacity, and the 
quickness of their movements, enable them to turn the 
flight of the largest birds, and even sometimes, when 
in captivity together, to overcome them. We have 
kept a sparrow hawk, ( Falco nisus ,) which, in the space 
of twenty-four hours that he was left unobserved, killed 
three falcons which were confined with him. 
The inextricable confusion reigning throughout the 
works of authors who have not attended to the 
characters of the different groups of this genus, renders 
it next to impossible to decide, with any degree of 
certainty, whether our Falco Cooperii has or has not 
been recorded. Though agreeing imperfectly with 
many, we have not been able, notwithstanding our most 
sedulous endeavours, to identify it with any. It is 
evidently a young bird, and we should not be surprised 
at its proving, when adult, a known species, perhaps 
one of the numerous species figured of late, and 
possibly Le Grand Epervier de Cayenne of Daudin, 
Sparvius major , Vieillot, stated to be one-third larger 
than the European sparrow hawk. At all events, 
however, it is an acquisition to the ornithology of these 
States ; and we have ventured to consider it as a new 
species, and to impose on it the name of a scientific 
friend, William Cooper of New York, to whose sound 
judgment, and liberality in communicating useful advice, 
the naturalists of this country will unite with us in 
bearing testimony, and to whom only the author, on 
the eve of his departure for Europe, would have been 
