2 PROFESSOR OWEN ON THE GENUS DINORNIS. 



Williams', more or fewer toe-bones have, nevertheless, been associated ; and, as their 

 numbers increased, their determination became facilitated. Already in the partial 

 restoration of the Dinornis giganteus in pi. 30 of my memoir of 1843, I had ventured to 

 sketch the probable proportions and disposition of the phalanges in each of the three 

 anterior toes, guided by the analogy of the Apteryx, in building up that part on the 

 basis of the few specimens of phalanges that then suggested the probability of such 

 analogy being correct. 



Each successive acquisition of additional phalanges has tended to support my original 

 supposition of the general resemblance of the foot of the Dinornis to that of the Apteryx : 

 and the rich acquisition of remains from Waikawaite in the Middle Island, transmitted, 

 in 1849, by the late Col. Wakefield, has enabled me to recompose the entire skeleton of 

 the foot of three species of Dinornis and Palapteryx, the largest appertaining to that 

 great bird which I had indicated in my memoir of 1846, p. 327, as probably being ' a 

 well-marked variety ' of the Dinornis giganteus. 



No specimens precisely corresponding with the characteristic femur, tibia and meta- 

 tarse of the Dinornis giganteus have, as yet, been transmitted from the Middle Island : 

 the homologous bones of similar size from Waikawaite present more robust proportions ; 

 and this difference is not only well-marked in the metatarse of the entire foot figured in 

 Plate I., but is accompanied by a well-marked articular rough depression for the Uga- 

 mentous attachment of the rudimental metatarsal of the back-toe (hallux), and also by 

 that characteristic bone of the genus Palapteryx (fig. 1, i). 



The general differences in the proportions of thickness to length will be appreciated 

 by comparing the metatarse of Palapteryx robustus, fig. 1 , in PI. I., with the metatarse of 

 Dinornis giganteus, vol. iii. pi. 27. fig. I. 



The subject of PI. I., which was obtained, like most of the bones transmitted by 

 Col. Wakefield, from the recent vegetable deposits at the mouth of the Waikawaite, is 

 in a much better state of preservation than the bones obtained from the more ancient 

 beds of the actual rivers in the North Island, described by the Very Rev. Archdeacon 

 Williams, in vol. iii. p. 237. The relative age of the present North and Middle Islands 

 of New Zealand, the question of their original union and of the period of their separation 

 — in short, all the geological and geographical deductions from the evidence of their 

 organized fossils — depend for their true solution upon a rigorous comparison and 

 exact determination of those fossils, and the progress of science will be proportionally 

 retarded by hasty and erroneous ascription of names to such fossils by those who may 

 have neither the leisure, the opportunity, or the skill for such comparisons. 



The principal dimensions and general form of the tarso-metatarsal bone of the Pal- 

 apteryx robustus are given in PI. I. fig. 1, where the anterior surface is represented of the 

 natural size ; other dimensions are recorded in the text. The compound nature of 

 this bone in birds generally is described in vol. iii. p. 243, and I may here premise that 



' Vol. iii. p. 237. 



