7S PEOFESSOE OWEN ON THE 



which the humerus presents in Penguins, Auks, and birds of prey, as compared with 

 that bone in the Dodo ; but a few words may be recorded of the comparison of the 

 humerus of the Dodo with that of the flightless bird of New Zealand, so nearly ap- 

 proaching to it in size, which bird is described in the 5th volume of the ' Transactions' 

 of the Society under the name of Cnemiomis (p. 395, pi. 66. figs. 7-10). In that extinct 

 species, although the humerus is 5^ inches in length, the parts indicative of the forces by 

 which it was worked are comparatively feebly developed. The ulnar tuberosity is nar- 

 rower, thicker, more obtuse, and its base has neither the upper nor lower excavation ; 

 it rises above the articular head, which is less prominent and narrower than in Didus ; 

 the pectoral ridge is shorter and situated lower down upon the shaft, not on the same 

 level with the radial tuberosity as it is in Didus ; the distal articulation is of the same 

 size as in Didus, but neither the radial nor the ulnar convexity is so prominent or well- 

 defined. 



The ulna of the Dodo is shorter absolutely, and much more so proportionally, than in 

 the Goura and most other volant Doves. In these it exceeds the humerus by about one- 

 foui-th its own length ; in Didimculus (PL XV.) it is a little longer than the humerus ; 

 in the Dodo (ib.) it is shorter than the humerus. The length of the ulna in Goura 

 covonata is 4 inches 6 lines; it is more bent than in the Dodo ; the quill-tubercles, seven 

 or eight in number, are more prominent ; nevertheless the rough depression for the 

 insertion of the chief flexor is less deep and less defined. The plumed winglet of the 

 Dodo would seem, therefore, to have been frequently and forcibly moved. 



In comparing the femur of the Dodo with that of the largest Dove, the bone appears 

 gigantic. The length of the femur in Goura coronata (PI. XXR^. fig. 11) is but 3 

 inches 3 lines, and it is more slender in proportion to its length than in the Dodo ; it, 

 however, repeats the few characteristics, if they may be so termed, of the Dodo's femur. 

 It has the pneumatic foramen in the same position, perhaps proportionally larger ; it 

 has the same large oblong surface for the ligament at the head of the bone ; the great 

 trochanter has the same form and disposition, but is not quite so much produced an- 

 teriorly ; there is a slight depression instead of a ridge for the trochanter minor ; the 

 fore part of the inner condyle is relatively thicker and less produced. The femur in 

 Otis and (Edicnemus has a thicker and shorter trochanter major, a more narrow and 

 shallow rotular channel ; it is shorter in comparison with the tibia, and more especially 

 witli the metatarsus, than in Didus and the Doves. 



The femur of Aptornis otidiformis^ is of the same size as that of the Dodo; but it has 

 no pneumatic foramen, the head is more hemispheroid and inclined forward, the liga- 

 mentous pit is deeper and more cu-cular, the supracei-vical articular surface is not 

 defined from that of the head, there is a wider and deeper depression at the fore 

 part of the proximal end of the femur, and a more prominent tuberosity on the back 

 part; the ridge continued from the back part of the shaft to that of the inner con- 



' Trans. Zool. Soc. vol. v. pi. 65. fig. 3. 



