Cu.I.] ° OF THE DODO. 107 
In Didunculus (Plate X. Fig. 9-9 e), and Phaps (Plate XI. Fig. 20-24), the metatarsus is 
elongated and slender, being of equal length in both, while they closely resemble each other in form and 
proportion ; in each, the flattened outer border is still broader than in Co/wmba, and the surfaces for the 
M. M. abductor annularis and abductor indicis are hence more reduced, from the encroachment of this 
border, which is widest in the centre, and contracts slightly downwards towards the inner trochlea. The 
area for the MW. extensor pollicis is relatively larger than in the arboreal Pigeons. The upper border of the 
ento-calcaneal process is straight in both ; in Didwnculus, the groove for the tendon of the M. flexor perforans 
pollicis is converted into a canal (Plate X. Fig. 9 d), and that for the tendons of the perforated flexors of 
the inner toe, is also nearlyclosed. In Pdaps, the outer ridge of the groove for the MZ. flexor perforans pollicis 
is very apparent, as in Columba. In Diduneulus, the trochlez are arranged exactly as in the Dodo; the 
groove for the tendon of the M. adductor annularis, is covered posteriorly by an osseous band, as in Lopho- 
lamus, and in Phaps, where it is narrower. In Phaps, the mner trochlea is more elevated than in the 
Dodo, but the outer is more abbreviated than in Didwneulus, and more like that in the Dodo ; the posterior 
metatarsal facet in both, is placed below the junction of the lower with the upper two-thirds of the bone. 
The elongation and relative slenderness of the metatarsus, the great breadth and flatness of the outer 
border, and the position of the articular facet, are reproduced in the Solitaire; and the inner margin, 
which is acute in Didunculus, is replaced in Phaps, by a narrow plane as in the Solitaire. 
In Geophaps (Plate XI. Fig. 26-30. Plate XII. Fig. 8), the metatarsus is shorter and more robust 
than in the two preceding species; and the outer margim, which is broad above, passes in the lower 
third of the shaft, into a narrow ridge separating the surfaces for the WM. MW. adductor and abductor 
annularis. The arrangement of the trochlez is preciselythe same as in the Dodo. In Geophaps, Phaps, and 
Didunculus, the tibialis tubercle encroaches on the inner inter-osseous foramen, as in the Solitaire, while in 
the Dodo, it is lower down. In Geophaps, as in Didunculus, the grooves for the perforated tendons of 
the inner toe, and the deep flexor tendon of the hind toe, are converted into canals. 
In Goura (Plate XI. Fig. 11-15), the metatarsus has nearly the same formas in Phaps, but the outer 
border is relatively narrower. In Phaps, Geophaps, and Goura, the ecto-calcaneal, however, is thicker than 
in the Dodo, &c., and is grooved externally for the tendon of the deep /leror of the hind toe. 
From these details we may therefore conclude, that the metatarsus of the Dodo possesses the family 
characters of that bone in the Colwmbide. 
In the typical Gal/ine, the calcaneal buttress is feebly developed and speedily subsides, and the shaft is 
thus more compressed in the antero-posterior diameter ; it is, however, as strongly marked as in Pigeons, in 
the short and robust prismatic metatarsus of Péerocles; and it is more apparent in the Cracide@ and Megapodide 
than in the common Cock. The external segment of the posterior surface is subconcave transversely, except 
in Péerocles. The ridge which supports the spur also distinguishes the metatarsus in the typical genera of the 
Galline ; that peculiar appendage is not the homologue of the 4a//uz, as has often been supposed. Swainson 
long ago pointed out its true nature ; it is really a portion of the dermo-skeleton, which becomes united to the 
metatarsal element of the ento-skeleton, by an extension of the ossific process in the intervening ligamentous 
texture; just as the teeth, which belong to the splanchnic division of the exo-skeleton, become anchylosed to 
the jaws in several fishes and reptiles. The /ind toe is the true hallux, and is present in the great majority 
of birds. It has the normal number of phalanges, namely, two, and is supported by the accessory 
metatarsus ; the outer, or fifth toe, is invariably absent in birds. In most of the Galdine, the tube which 
transmits the tendon of the W. fleaor digitorum perforans pierces, as it were, the thickness of the ento-calca- 
neal process, and opens below upon, or to the mner side of the calcaneal buttress, which runs up to terminate 
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