PEOFESSOE OWEN ON THE GENUS DINOENIS. 259 



The proportions of the tibia and metatarse of the present subject do not accord with 

 those of the corresponding bones of Dinornis casuarinus given in "The Table of 

 Admeasurements" (Trans. Zool. Soc. vol. viii. 1873, p. 370)'. 



The following dimensions, which I have been able to take of the tibia and metatarse 

 of the present acquisition, may be compared with those in the volume above cited : — 



Tibia, Dinornis didinus. ■ ,• 



' in. lin. 



Length 15 3 



Bi^eadth of proximal end 3 7^ 



Breadth of distal end 2 4 



Breadth of middle of shaft 13 



Metatarse, Dinornis didinus. 



Length 6 9 



Breadth of proximal end 2 4 



Breadth of middle of shaft 16 



In a compari.?on with the ' admeasurements ' quoted above, it wiU be seen that the 

 present species accords best -with Dinornis didiformis^. But there are differences ; and 

 what 1 i-egard as a significant one is the indication, in the present species, of the larger 

 proportional size of the phalanges supporting the back toe (i). 



The instances in which evidence of that toe had been recognized by an indication of 

 the .surface for the ligamentous joint of its metatarsal with the tibia led me in 1872 to 

 abandon the ground on which a genus Palaxiteryx had been separated from that called 

 Dinornis, and to include both under the same generic term. 



The short and feeble metatarsal of digit i was subsequently recovered in connexion 

 with a tibia in which the joint-surface in that bone was inconspicuous. But no 

 specimens of the metatarsal and jihalangial bones of the back toe had indicated the 

 functional development and strength manifested in the subjects of Plates LX., LXI. 



Were it not for the comparative shortness of this toe, the foot, now recovered with 

 its integument and claws, might be suspected to be that of a huge raptorial bird, rather 

 than of a terrestrial phytophagan deprived of wings. 



The length of the back toe (i) including the claw, where the toe projects from the 

 tegument of the foot, following the convex curve, is 3 inches 10 lines ; the corresponding 

 admeasurement of the mid toe (iii) is 10 inches 6 lines. The accompanying figures of 

 the right, and best-preserved, foot being of the natural size, other admeasurements are 

 omitted. The proportions of the digits ii and iv are those of the genus. 



The best-preserved claws are subobtuse, canaliculate beneath, the wide and shallow 



' Dinornis, Part sviii. (1872). 

 ' Trans. Zool. Soc. vol. viii. p. 375. 



2b2 



