RAP TORES: BIRDS OF FREY. 
497 
present or al>soiit. Hallux always present, usually valid and insistent ; outer toe reversible in 
some cases, never permanently reversed. The ambiens is present (except in Striges) ; all ex- 
cepting Gi/jJogeranides and some Cathartides possess the femoro-caudal muscle, but not its 
accessory, nor the semi-tendinosus nor its accessory (excepting Cathartides, which have the two 
last named, and G^jpogeranides, which have these and the accessory femoro-caudal). Coeca 
are present (except in Cathartides). The oil-gland is present in aU, and tufted except in 
Cathartides. Aftershafts are present (usually), lacking in some Accipitres, all Striges and 
Cathartides. There are two carotids ; the syrinx, when developed, has but one pair of intrinsic 
muscles. The nature is altricial, yet ptilopsedic, the young being downy when hatched, and 
long fed by the parents in the nest. The alimentary canal varies with the families, but differs 
from that of vegetarian birds, in adaptation to an exclusively animal diet. In the higher 
types, the whole structure betokens strength, activity, and ferocity, carnivorous propensities 
and predaceous nature. Most of the smaller, or weaker, species feed much upon insects ; 
others more particularly upon reptiles, and fish ; others upon carrion ; but the majority prey 
upon other birds, and small mammals, captured in open warfare. To this end, the claws no 
loss than the beak are specially adapted, by their development in the talons " which we con- 
stantly associate with our ideas of birds of prey. These weapons of offence and defence are 
as a rule of great size, strength, crookedness, and acuteness ; and also peculiar in being con- 
vex on the sides, gradually narrowed to the point, and little or not excavated underneath. The 
inner claw is larger than the outer, and the hinder one smaller than the middle ; and all are 
very flexibly jointed, so that they may be strongly bent underneath the toes, carrying to the 
extreme the grasping power of the feet. The legs are muscular and largely free from the 
body, feathered to the suffrago or beyond ; when unfeathered, the tarsal envelope varies in 
character. The wings are ample, and, as usual in birds below Passeres, the coverts are k)ng 
and numerous, covering three-fourths or more of the folded wing. The tail, very variable 
in shape, has twelve rectrices (with rare exceptions). 
Representatives of this order are found in every part of the world. They are divisible into 
four primary groups, of more classificatory value than that attaching to average families in 
ornithology, and therefore to be held as superfamilies or suborders. One of these, Gypogeranides, 
consists of the single remarkable species Gypogeranus serpentarius, the secretary-bird or serpent- 
eater of Africa ; this shows a curious grallatorial analogy, being mounted on long legs like a 
Crane, and has several important structural modifications. The other three are the Striges or 
Owls ; the Accipitres or Hawks, Eagles, etc., including the Old World Vultures ; and the 
Cathartides or American Vultures, — these last more difterent from the others collectively than 
the rest are from one another. All are well represented in this country. They are recognizable 
at a glance, but the following analysis will serve to place the characters of the suborders and 
their respective families in strong relief. 
Analysis of Suborders and Families. 
Feet scarcely raptorial, with weak, blunt, lengthened, little curved or contractile claws. Hind toe ele- 
vated, not more than half as long as outer toe, with small claw ; middle toe lengthened ; outer toe not 
versatile; front toes all webbed at base; basal joint of middle toe longer than either of the succeeding 
ones. Nostrils large, perforate. Bill little raptorial, lengthened and somewhat contracted in conti- 
nuity, tomia never lobed or toothed, tip blunt, little hooked. Head largely naked. Index digit with 
a large claw. No lower larynx, coeca, aftershafts, or tuft of oil-gland. Ambiens present ; femoro- 
caudal present or absent; semitendinosus and its accessory present CATHARTIDES. 
Diurnal ; gressorial ; feed exclusively on carrion Cathartics. 
Feet highly raptorial, with large, strong, sharp, curved, contractile claws. Hind toe not elevated, length- 
ened, more than half as long as outer toe, with large claw; outer toe often versatile; front toes with 
slight basal webbing between outer and middle, or none. Nostrils small, imperforate. Bill short, 
stout, very seldom contracted in its continuity, tomia often once or twice lobed or toothed, tip sharp, 
much hooked. Head feathered completely or in greatest part. Lower larynx with one pair of intrinsic 
muscles. Coeca present. Plumage with or without aftershafts. Ambiens present or absent. Femoro- 
caudal present. Semitendinosus and its accessory absent. As a rule, saltatorial, and kill their prey. 
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