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back part of this end of the bone, divided by a deep round groove for 

 the flexor tendon of the toes : the ridges are supported by a thick longi- 

 tudinal eminence, which is continued down the middle of the back 

 part of the bone, gradually subsiding as it descends. On each side of 

 the upper part of this median longitudinal eminence there is a foramen, 

 as in most other birds, from which a shallow and narrow longitudinal 

 canal is continued for some distance down the bone : there are no other 

 canals, nor any longitudinal angular ridges at the back part of the meta- 

 tarsus ; nor is there the slightest trace of a surface for the attachment of 

 a hind-toe. On the anterior part of the bone, near the proximal end, 

 there is the usual depression, in which the canals continued from the 

 two posterior foramina terminate by a single foramen : below the de- 

 pression there is a rough surface for the insertion of the tendon of the 

 tibialis anticus, from which point a median wide and shallow channel 

 extends a certain way down, and divides into two shallower depressions, 

 which diverge to the interspaces of the distal articular condyles : the 

 margins of all these depressions are rounded off, and the general surface 

 of the anterior, as of the posterior part of the metatarsus, is smooth and 

 rounded : this, with the great breadth of the bone as compared with the 

 metatarsi of other Struthinnida and tridactyle Gratia, constitutes the 

 principal generic character of the tarso-metatarsal bone in the Dinornis. 

 The interspaces of the three articular terminations are wider, the two 

 lateral ones diverging more, and being of larger size than usual ; they 

 have also the median trochlear groove, but not so deep as in the middle 

 articular process. 



The length of the tarso-metatarsal bone in the gigantic Dinornis is a 

 trifle more than half that of the tibia. In the tridactyle Emeu the tarso- 

 metatarsal bone is as long as the tibia ; in the Ostrich and the Bustard 

 it is a little shorter than the tibia. The still shorter proportion which it 

 bears to the tibia in the Apteryx of New Zealand forms a striking re- 

 semblance between this bird and the Dinornis. But the Apteryx is 

 distinguished from the larger Strulhionida, not more by its elongated 

 slender bill than by the presence of a fourth small toe on the inner and 

 back part of the foot, articulated to a slightly raised rough surface of the 



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