376 PEOFESSOE OWEN ON THE GENUS DINOENIS. 



boues referable by length to this species, two varieties are indicated by metatarsals'; 

 the longer and more slender form, contributed by Dr. Lillie (fom. cit. infra, p. 500), 

 may prove to be a variety so well established and so characterized by concomitant 

 modifications in other parts of the skeleton as to need, for convenient reference, a 

 distinct name, for which that of Dinoniis alius may be accepted. 



In comparing the skulls, indicative of eight or nine of the fifteen species of Dinornis 

 characterized by limb-bones, we see that they difi'er in the relative length of the beak^ 

 and in that of the terminal osseous part of the upper mandible^ to the rest of the 

 skull, in the sharper or more obtuse termination of both mandibles^, in the relative 

 antero-posterior extent of the temporal fossae % in the relative flatness or transverse con- 

 vexity of the cranium^ in the longitudinal contour- of the upper part of the skull ''j and 

 in a few such minor particulars as the breadth and direction of the postorbital process. 



The sternum of Dinornis, whilst conforming to the apterygian type', shows two well- 

 marked modifications thereof — in the proportions of breadth to length, and in the 

 degree of divergence of the lateral processes^. 



The back toe [hallux, i) was a small functionless appendage to the foot in the best- 

 developed condition in which it has been found'". The trace of the ligamentous 

 attachment to the functionally developed metatarsus is feeble in the species in which 

 the existence of this toe is most certain. It cannot be inferred to have been wholly 

 absent in the cases in which the connecting ligaments have left a less definite trace or 

 where such is undistinguishable. I have therefore felt obliged to abandon this ground 

 of generic distinction". 



One is naturally disposed to group together the thick-legged or strong-limbed species 

 of the South Island represented by the five above cited. It would seem that the 

 broader type of sternum was associated wdth such proportions of the limb-bones in 

 those species. If such association should be proved and found to be constant, and if 



' Trans. Zool. Soc. vol. vi. pi. 89. figs. 4 & 5. 



' Compare Trans. Zool. Soc. vol. v. pi. 55. fig. 1 (Dinornis robustus), with ojJ. cit, vol. vii. pi. 13. fig. 1 

 (Dinornis casuarinus). 



' Compare op. cit. vol. vii. pi. 15. fig. 1 (Dinornis ingens), Tvith op. cit. vol. vii. pi. 11. fig. 1 (Dinornis crassus). 



* Compare op. cit. vol. vii. pi. 11. figs. 2, 3, 8, & 9 (Dinornis crassus), with op. cit. vol. vii. pi. 10. figs. 6-9 

 (Diiwrnis eiepliantojms). 



' Compare op. cit. vol. v. pi. 53. fig. 1 (Dinornis robustus), with Jaeger, Palaontologie der Novara Expedition, 

 art. vi. Berioht iiber einen fast vollstandigen Schadel von Palapteryx ingens, Taf. xsvi. fig. 2. 



' Compare op. cit. vol. vii. pi. 10. fig. 2 (Dinornis elephantopv.s) , with op. cit. vol. iv. pi. 24. fig. 1 (Dinornis 

 ijiganteus). 



' Compare op. cit. vol. v. pi. 55. fig. 1 (Dinornis robustus), with op. cit. voL vii. pi. 11. fig. 1 (Dinornis crassus), 

 or with op. cit. vol. vii. pi. 13. fig. 1 (Dinornis casuarinas). 



» Trans. Zool. Soc. vol. ii. p. 290, pL 55. figs. 2 & 3, vol. vii. p. 118. 



' Compare op. cit. vol. vii. pi. 7. fig. 1 (Dinornis elephantopus), with op. cit. vol. vii. pi. 8. fig. 1 (Dinornis 

 rluides). 



'° Op. cit. vol. iv. pi. 1. figs. 4 & 5 (Dinornis robiutus). " Trans. Zool. Soc. vol. vii. p. 119. 



