PROFESSOR OWEN ON THE GENUS DINORNIS. 377 



in like manner the narrower form of sternum shown in Dinornis rheides should be 

 found to prevail in the six slender-limbed species, we shall have the same ground for 

 restricting to them the old generic term. If it could be shown that Palapteryx, as 

 above defined, had the hallux, and that Dinornis, as above restricted, had it not, the 

 grounds of the generic or subgeneric division would be strengthened. 



But when we come to consider the species manifesting the cranial modifications 

 above specified, we find what would otherwise afford the most satisfactory generic 

 character failing us. Dinornis rohustiis resembles most Dinornis ingens in the form 

 and proportions of skull and beak. Dinornis elejihantojjus, which most closely 

 resembles in limb-characters and sternum Dinornis crassus, most differs from that 

 species in the form and proportions of the mandibles. 



But much yet remains to be recognized as to the cranial characters of the species of 

 Dinornis indicated by other parts of the skeleton. No skull of any of the species 

 represented by remains in the North Island has yet been found at all comparable in 

 the state of its preservation or entireness to those discovered in the South Island. The 

 North-Island Moa-bones, as I have before had occasion to remark, are more mineralized, 

 or more changed from their recent state, than those from the swamps and turbaries of 

 the South Island. The least incomplete of the crania from the North Island is that 

 figured in pi. 54 of vol. iii. of the Transactions of this Society, where it is provisionally 

 referred to Dinornis geranoides. 



Many years may elapse before examples of the skeleton of the slender-limbed species 

 of the North Island are found in such proportion and juxtaposition as to warrant con- 

 fidence in the ascription to each of its cranial characteristics. The inferential restora- 

 tions of some of the South-Island Moa-skeletons, in respect at least of the skulls, may 

 need rectification as the result of more fortunate discoveries. 



In the present condition therefore of my information respecting the extinct Moas, I 

 deem the means of imparting it to be satisfied by the use of one generic term, with a 

 grouping together of the species on the ground of well-marked differences of thickness 

 in relation to length of femur, tibia, and metatarsus, and more especially as shown by 

 the last-named bone. 



VOL. VIII. — PART Ti. May, 1873. 3 h 



