FALCO COMMUNIS. 
299 
These handsome birds do not usually hover, like the Sparrow Ilawk, when hunting hut 
course rapidly along and pounce upon their victim without giving it an instance’s warning 
of their presence; thus they appear to capture their prey with great certainty. Their cry, 
when moving, is shrill and loud hut different from the well-known rattle of the Sparrow 
Hawk. 
Although these Hawks usually breed considerably north of Massachusetts, I am con¬ 
fident that the eggs will yet be taken in the state, for I once had a female which was shot 
during the breeding season, early in June, and which exhibited every mark of incubation, 
while other instances of a similar nature have come to my knowledge. As remarked, 
however, the Pigeon Hawks occur with us, more abundantly during the autumnal migra¬ 
tion than at any other season, although they are tolerably common in spring. 
FALCO COMMUNIS. ' 
Peregrine Falcon. 
Falco communis Gm., Sysfc. Nat., I; 1788, 270. 
DESCRIPTION. 
Sp. Ch. Form, robust. Size, large. Sternum, stout, rather narrow, with the marginal indentations quite large. 
Tongue is short, thick, quite fleshy, about the same width for nearly its entire length, horny at tip, where it is round¬ 
ed, bifid, and grooved beneath.. Tail, slightly rounded, with the feathers somewhat acuminate. Wings, with only one 
outer quill incised. Tarsus, slightly feathered in front. Ooeca, present but very small. 
Color. Adult male. Above, including upper wing coverts, secondaries, and upper tail coverts, dark bluish-slate, 
transversely banded with dark-brown which becomes lighter on the rump. Primaries and tail, dark-brown, the former band¬ 
ed on the inner webs with yellowish-white; the latter tipped and banded with ashy-yellow. Under parts, including sides of 
head, under wing coverts, under tail cover t=, and tibia, yellowish-white, spotted on the breast and abdomen, and trans¬ 
versely banded on the remaining portions with black. There is also a black patch on the cheeks. Forehead, white. 
Adult female. Quite similar to the male in general coloration but darker above, and tinted below with bulf. In the 
adult stages, the feet are yellow and the cere, green. 
Yount/. Much browner above than in the adult female. The under parts are tinged with reddish and longitudinal¬ 
ly streaked with dark-brown. The cheek patches are broader and the wing feathers are tipped with yellowish-white. 
Young of the year. Show no traces of ashy above, and the top of the head is overwashed with yellowish-rufous, es¬ 
pecially on the forehead and occiput. There is a line of reddish extending over the eye, while every feather above is edged 
with it. The tail is tipped with white, barred on inner webs with deep rufous and the same color pervades below. The 
under tail coverts are barred. 
Nestlings. Are at first covered with white down, then gradually assume theplumage last described. In this and the 
last two stages, the cere is dark-green and the feet, blue. Bill, black, blue at base, and iris brown, in all stages. 
OBSERVATIONS. 
Specimens of the same age exhibit the usual amount of variation regarding intensity of color, size of spots, width of 
bands, etc., but the species may be known at once by the large size, dark cheek patch, and other colors as described. Dis¬ 
tributed, as asummer resident, among the mountains or along rocky sea-boards, throughout Eastern North America, above 
latitude 38°. Winters in the more Southern portions. 
DIMENSIONS. 
Average measurements of male specimens from Eastern United States. Length, 17-50; stretch, 38-50; wing, 14-25; 
tail, 725; bill, "72; tarsus, 1-72. Longest specimen, 18"00; greatest extent of wing, 39-00; longest wing, 14"50; tail, 7 50; 
bill, -75; tarsus, 1 75. Shortest specimen, 17-00; smallest extent of wing, 38‘00; shortest wing, 14-00; tail, 7 p 00; bill, -70; 
tarsus, i - 70. 
Average measurements of female specimens from Eastern United States. Length, 19-00; stretch, 41-00; wing, 15-00; 
tail, 7 75; bill, "78; tarsus, l - 75. Longest specimen, 20"00; greatest extent of wing, 42-00; longest wing, 15-50; tail, 8 00; 
bill, -80; tarsus, T80. Shortest specimen, 18 - 00; smallest extent of wing, 40-00; shortest wing, 14'50; tail, 7 - 50; bill, "75 
tarsus, 1-90. 
