FALCO SPARVERIUS. 
295 
GENUS I. FALCO. THE TRUE FALCONS. 
Gen. Cir. Bill, short, broad, well curved, ivilh the cutting edge of upper mandible, distinctly toothed, and the lower, 
notched. Tarsus, not long and nearly naked. Tail, slightly rounded, not exceeding in length one half the length of the wings 
which are considerably elongated and pointed. Nostril, with central tubercle. 
Members of this genus have the leg short, and the tarsus is usually naked to the heel behind, but is slightly feathered 
in front. The toes are long and the claws are quite short but pointed. Only one or two outer quills are noticeably incised 
on the inner web. 
The trachea is a little flattened throughout. The sterno-trachealis is short and stout, having its-origin quite near the 
larynx, and there is a slender bronchialis extending over all the half rings, but there are no other laryngeal muscles. The 
tympaniform membrane is present and although there is a thin os transversale, it does not support a semilunar membrane. 
The walls of the oesophagus are thin; this is at first nearly straight, then is dilated into a crop, and is again straight and 
opens into a rather large proventriculus with numerous small, simple, oval glands arranged in a zonular band which meas¬ 
ures '70 in columbarius, from which this and the following dimensions were taken. The stomach is ofa rather small size, 
somewhat globular in form, with thin but soft walls, and is lined with a soft membrane. The fold of the duodenum is long, 
measuring 3 00, inclosing an irregularly formed pancreas which only extends about one half its entire length. The coeca, 
when present, are very small. The spleen is an elliptical body lying on or near the proventriculus. Both lobes of the liv¬ 
er are short, thick, and nearly equal in size. The heart is large and not very pointed. There are four species within our 
limits. 
FALCO SPARVERIUS. 
Sparrow Hawk. 
Falco sparverius Linn., Syst. Nat., I; 1766, 128. 
DESCRIPTION. 
Sp. Ch. Form, rather slender. Size, small.- Sternum, stout, with the marginal indentations quite large. Tongue, 
short, not very fleshy, and about thesame width for nearly its entire length, then rounded, bifid, and grooved beneath. Tail, 
considerably rounded. Wings, with two outer quills incised. Tarsus, slightly feathered in front. There are no traces of 
any coeca. 
Color. Adult male. Top of head, upper wing coverts, and secondaries, bluish-ash, with the two latter more or less 
spotted and barred with black, which usually extends Ovqr the middle of the secondaries. Back, rump, upper tail coverts, 
and basal portion of tail, excepting outer webs of outer feathers, bright cinnamon. Tip of tail, outer web of outer feather, 
and sometimes the entire feather, white, with a subterminal band of varying width, extending across the entire tail, and 
bandings on outer feather, black. Primaries, dark-brown, barred on the inner webs with white. Throat and sides of 
head, white, the latter having two black spots, one in front of the ear coverts, nearly reaching the eye, and the other back 
of them. There is a narrow line of black crossing the occiput, and the back is more or less banded with it. Under wing 
.coverts, white, barred and spotted with black. Remainder of under parts, including under tail covert« and tibia, white, 
overwashed, to a greater or less extent, with cinnamon, spotted on the sides and flanks with black. The top of the head 
is marked with a spot of cinnamon. 
Adult female. Similar to the male in general coloration but lack the bluish-ash of the upper wing coverts and sec¬ 
ondaries, which are pale cinnamon, barred with black, and these markings extend over the back and tail. The tints below 
are paler, and are streaked, excepting on the throat, under tail coverts, and tibia, with reddish-brown. 
Young. Quite similar to the female but are more finely barred above and these markings extend over the rump and 
upper tail coverts. 
Nestlings. Are at first covered with a yellowish down, then gradually assume the plumage last described. Bill, black, 
blue at base, cere and feet, orange, iris brown, in all stages. 
OBSERVATIONS. 
There are, perhaps, few birds which show a greater amount of variation in markings than the present species. This 
is especially noticeable in the males. Two specimens, shot in Southern Florida, present the extremes; one being nearly 
white on the under portions, and the other, deep-cirnamcn even on the under tail coverts and tibia. Thedarkone has but 
little cinnamon on the head yet the whiter specimen has this color extending over a greater part of the crown. Sometimes 
the bluish-ash of the wings is extended on to the back and in a skin from Miami, this tint crops out in patches on the upper 
tail coverts and tail. Notwithstanding these variations, this species may.be at once known by the cinnamon-red and other 
colors as. described. Distributed, as a summer resident, throughout North America. A constant resident south of Mass¬ 
achusetts, where they are not as large as those from further north. 
