Steigim:.] OSTEOLOGIA AVIUM. [Bubonin^. 



Remarks on the Oedee Raptoees. 



The Order Eaptores is well distinguished from other Orders by its external structure, 

 being that adapted for preying on other animals ; as, however, it is my object in this 

 work merely to point out osteological characters, I shall not go into those which may 

 be made out by external examination, such as the bill and claws. The cranium of 

 Raptorial Birds is remarkable for its breadth in proportion to its length, and the hooked 

 form of the upper maxillaries ; the lacrymal bones are always long, and extend back- 

 wards over the orbits ; the orbital septum is in old birds quite, or nearly, perfect ; there 

 is always an indentation more or less apparent at the base of the nasal bones; the 

 upper maxillaries cover a very small portion of the roof of the mouth ; the palatine 

 bones have invariably a downward fold on their interior edges, and do not approach to 

 one another except at their posterior internal angles ; they are always articulated to 

 interarticular bones intervening between them and the ossa quadrata ; there is always a 

 well-marked muscular impression above the aural orifices, in many instances amounting 

 to a channel for the reception of the masseter muscles ; the nasal orifices are generally 

 small, particularly in the typical species of Falcons. The skeleton generally is very 

 strong and powerful ; the sternum is very slightly narrower on its anterior, than on its 

 posterior margin, and either approaches the form of a parallelogram, — the breadth of the 

 posterior margin being equal to two-thirds the whole length, as among the Falcons, — 

 or that of a square, as among some of the Owls ; it is always more or less convex longi- 

 tudinally and transversely ; the keel is deep, and its inferior edge is more or less arched. 

 The pelvis is large and broad, and the ilium from the cotyloid cavity backwards always 

 overhangs the edge of the ischium, which is placed nearly perpendicularly to the 

 superior plane of the former. The ischiadic foramen is large and rounded, the obturator 

 foramen is composed of a slight fissure between the os pubis and the ischium, ending 

 anteriorly in a rounded opening just behind the cotyloid cavity. The rami of the 

 furculum are either broad and laterally flattened for their whole length, as among the 

 Falcons; or else narrowed as they approach the sternum, as among the Owls and 

 Vultures. In the latter family, the furculum, instead of being united to the sternum 

 by a ligament near the point of keel, is united to that bone very near the manubrial 

 process. The coracoids are very strong and short, nearly triangular in the middle, and 

 very much expanded at their articulation with the sternum, which is always by means 

 of a shallow transverse groove in the latter bone ; the scapula is much expanded at its 

 distal extremity, and obliquely sloped on its upper edge to a point at the tip; the 

 proximal half is narrower than the distal, not so much expanded ; it is very slightly 

 bent downwards for its whole length ; there is a depression on the outer surface near 

 the tip extending for about one-third of its length. The humerus is very strong ; the 

 ridge for the attachment of the pectoral muscles very highly developed; the ulna is 

 somewhat triangular; the posterior metacarpal bones are nearly straight among the 

 Falcons, and more or less arched among the Owls and Vultures ; throughout the whole 

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