Zoological Society. 277 



any of the Vulturidce, or than that of the Cock, the Crax, or any of 

 the Gallince or existing Strut hionidce; the stronger-footed species of 

 Dinornis most resemble it in the general proportions of the tarso- 

 metatarsus, but greatly differ in the particular configuration of the 

 bone, and in the absence, or feebler indication, as in the subgenus 

 Palapteryx, of the articulation for the metatarsal bone of the back- 

 toe. The relative size of this bone is greater in the Dodo than in 

 any other known bird. The Eagles make the nearest approach to 

 it in this respect ; as also in the shape of the hinder supplemental 

 metatarsal, the breadth of its distal end, and its peculiar twist back- 

 wards and outwards, so as to form a bridge or pulley against which 

 the flexor tendon of the hind-toe plays. This half-twist of the rudi- 

 mental hind-metatarsus is feebly repeated in the Gallince, but the 

 bone is much less expanded at its lower articular end, especially in 

 the Crax ; whilst the more typical Gallince are further distinguished 

 from the Dodo by their spur. 



The Apteryx is the sole existing Struthious bird which possesses 

 the hind-toe ; but it is very much smaller than in the Dodo, and the 

 supporting metatarsal bone is devoid of the distal twist and expanded 

 trochlea. The upper end of the tarso-metatarsus of the Dodo is re- 

 markable for the great development of its calcaneal process, from 

 which a strong ridge descends, gradually subsiding, half-way down 

 the bone. The posterior surface of the calcaneal process is broad, tri- 

 angular, vertically grooved and perforated at its base. In the Eagle the 

 corresponding calcaneal process is a compressed, subquadrate ridge, 

 whose base of attachment is not much longer than the obtuse end, 

 and this is neither grooved nor perforated. In the Cathartes Cali- 

 fornianus the calcaneal process is thicker than in the Eagle, shaped 

 more like that of the Dodo, with a ridge descending upon the meta- 

 tarsus, but it has a double groove behind. 



In the Common Cock the calcaneal process more resembles that 

 in the Dodo than the Vulture's does, but it is not so broad. 



With regard to the first or proximal phalanx of the hind-toe, that 

 of the Haliaetus is larger and broader, especially at its base, stronger 

 in proportion to its length, but longer in proportion to the sustaining 

 metatarsus. 



In the Vultures the proximal phalanx is not only longer in pro- 

 portion to the metatarsus, but is more slender than in the Dodo. 

 The same bone is also longer and more slender in proportion to the 

 small supporting metatarsal bone in the Cock, the Crax, and all other 

 Gallince ; in fact, the Dodo is peculiar among Birds for the equality 

 of length of the metatarsus and proximal phalanx of the hind-toe. 

 With regard to the three trochlear extremities of the principal 

 coalesced metatarsals, the middle one in all Gallince is longer in pro- 

 portion than in the Dodo, in which the inner one is nearly as long 

 as the middle one, the outer one being the shortest. In the Eagle 

 the inner division is of quite equal length with, or is longer than the 

 middle trochlea ; the proportions of the three trochleas in the Vul- 

 tures corresponding best with those in the Dodo. Another character 

 by which the Dodo resembles the Vulture more than the Eagle is 



