70 ME. C. "W. ANDREWS ON THE SKULL AND 



The Bones of the Wing. 



The exact length of the wing cannot be determined, owing partly to the incomplete 

 state of the humerus and partly to the absence of the phalanges ; but it is certain that, 

 in proportion to the bulk of the bird, it had undergone extreme reduction and must 

 have been entirely useless for purposes of flight. At the same time the stoutness of 

 the bones and the distinctness of the muscle-impressions indicate that it was in some 

 way functional, and the presence of a series of tubercles along the posterior border of 

 the ulna shows that it was provided with a series of large quill-feathers, the remiges. 

 It may have been employed to assist the bird in running, or possibly as a shield, 

 somewhat in the same way as the Secretary-bird is said to use its wings, although for 

 this latter purpose it would appear to have been too small. 



Of the humerus (Plate XVII. fig. 8) only the distal end is preserved in the type- 

 skeleton. In it the radial (r.) and ulnar condyles (u.) are of the ordinary avian form, 

 but are less distinctly separated than usual, the intercondylar groove being almost 

 obsolete. The surfaces of the condyles are rough, and probably a considerable pad ot 

 cartilage intervened between them and the bones of the forearm. The distal border of 

 the bone is very oblique, owing to the presence on the ulnar side of a pointed process 

 projecting some distance beyond the ulnar condyle (m.). The anterior face of the bone 

 above the condyles is deeply concave, and the portion of the concavity close to the ulnar 

 border of the bone contains the well-marked elongated impression of the brachialis 

 anticus (b.a.). Posteriorly there is a shallow olecranon fossa. 



The ulna (Plate XVII. fig. 4) is a short, very stout bone ; its shaft is slightly curved 

 and triangular in section, the sharpest angle forming its posterior border. At its 

 proximal end the impression of the brachialis anticus is not very clearly marked, but 

 the surface for the humero-cubital ligament is very distinct. There is a well-developed 

 olecranon process (ol.), the end of which bears a rugose surface for the insertion of the 

 triceps tendon, and from this a slight ridge runs to another rugosity (for the insertion 

 of the long head of the triceps) lying immediately below the edge of the radial 

 glenoidal surface. On the postero-internal border, immediately below the articular 

 surfaces, is a tuberosity for the insertion of the biceps tendon. The sharp posterior 

 border of the bone bears a series of well-marked tubercles, indicating the existence of 

 large quill-feathers (secondary remiges) in the wing: there are about seven of these 

 tubercles. 



Towards its distal end the shaft loses its triangular form and becomes circular in 

 section. 



The distal articular head is large, and on its outer surface there are impressions 

 marking the origin of various flexor muscles of the digits, and a groove for the passage 

 of tendons. The length of the ulna is approximately 110 mm. 



The radius (Plate XVII. fig. 5) is represented by the proximal end only. 



In the metacarpus (Plate XVII. fig. 6) the proximal articular surface is broad and 



