OSTEOLOGY OF THE DODO. 63 



and shows the narrow oblong surface for the articulation and ultimate confluence of the 

 clavicle (ss). The coracoid unites with the scapula at an angle of 100°. 



The clavicle (ib. figs. 4 & 5, 58), at its scapular end, is slightly expanded, compressed, 

 vnth an obtuse recurved termination articulating with the above-named surface of the 

 coracoid, and in one instance coalescing therewith, and by extended ossification with the 

 " acromion scapulae" (ib. figs. 8 & 9). As the clavicle descends it curves slightly and 

 contracts to a point. The angle at which the pair meet is shown in figs. 4 & 5. 



§ 7. Bones of the Wing. (Pis. XV. & XX. figs.. 12-17.) 

 Of the humerus the series contains two specimens, both measuring 4 inches 3 lines in 

 length, one right, and the other left (PI. XX. figs. 12-14), but differing slightly in their 

 proportions and in colour — one being of the olive-brown tint with which most of the 

 bones are stained, the other black. The articular head (ib. a) is an elongate oval con- 

 vexity, with the larger end toward the radial side, prominent toward the back and rather 

 flattened toward the front of the bone, which there swells out beyond the base of the 

 articular surface. The radial tubercle is small, and descends from the radial end of the 

 head for about 5 lines; the pectoral process (ib. b) is triangular, obtuse, short, and 

 bent, or directed toward the front side of the bone : the ulnar tuberosity (ib. c) is more 

 produced in that direction ; it is oblong, obtuse, -with its base impressed by a large pit 

 both above (fig. 12, h) and below — the lower one (ib. rj) being the deepest, and perforated 

 by a pneumatic foramen ; the convex, broad, ulnar border of this tuberosity has two 

 slightly produced processes, an upper or posterior (ib. fig. 12, c) and a lower and internal 

 (ib. (j), which is the smallest. The breadth of the proximal end of the humerus, across 

 the tuberosities, is 1 inch 5 lines, beyond them the bone contracts to a smooth subcylin- 

 drical shaft, showing at the back part of the proximal thii-d a longitudinal ridge (fig. 12, r), 

 half an inch in length; it gradually expands at the distal third to a breadth of 10 lines, 

 where the articulations offer the usual avian characteristics of the elbow-joint. The 

 head of the humerus is occupied by a fine cancellous structure : into the large vacuity 

 below this, crossed in the section figured (PI. XXIII. fig. 5) by a transverse slender bar 

 of bone, the small pneumatic foramina at the bottom of the wide and deep fossa for the 

 axillary aii--cell open. The part of the hollow proximal end giving off the pectoral 

 and other processes for the attachment of muscles is strengthened by similar abutments. 

 The pneumatic cavity of the main part of the shaft of the humerus is simple, with a 

 compact wall thicker than at the ends of the humerus, but not exceeding that which is 

 characteristic of the long air-bones in birds. The portion of the distal end chiefly 

 serving for muscular attachments and the antibrachial articulation are also cancellous. 



The radius (Pis. XV. & XX. fig. 15) is a straight and slender bone, 3 inches 1 line in 

 in length, and 2 lines in chief diameter of the shaft. The proximal articular surface is 

 subcircular, 3 lines in diameter, moderately concave ; the distal end expands to the same 

 extent, but is compressed, as usual. 



