60 Zoological Society. 



face, with the median linear notch at its base, — all demonstrate that 

 in this characteristic part of the skull the New Zealand bird repre- 

 sented by it most resembled the genus Nestor, — a singular nocturnal 

 Parrot at present only known as a denizen of that island. 



Thus then it appears that the indications of two genera, with 

 several species of terrestrial birds of large or gigantic size, deduced 

 in the Author's former Memoir (Part II.) from bones of the legs, are 

 most fully and satisfactorily confirmed by the evidence of the subse- 

 quently received bones of the head and beak. 



The form and structure of these characteristic parts in one of the 

 genera (Dinornis) are so peculiar, that the author does not refer the 

 genus to any known natural family of birds. Its location in the 

 order Struthionida implies little more than an arrested development 

 of wings, and an exaggerated development of legs, organized for 

 progression on dry land. 



As, however, there are strictly aquatic forms of birds deprived, by 

 a low development and special modification of the wings, of the power 

 of flight, so also there are, in other natural groups of birds, aberrant 

 forms similarly debarred from the privilege and enjoyment of the 

 characteristic kind and field of locomotion of their class. Apart from 

 the true Struthionidce, we have an instance of this in the Brachy- 

 pteryw or modified Rail of New Zealand ; the Dodo is a second in- 

 stance, whether it be regarded as an aberrant Vulture or a modified 

 Pigeon, according to the views entertained by Mr. Gould and sup- 

 ported, with new arguments, by Mr. Strickland, before the British 

 Association at Oxford, and which will be fully elucidated in the 

 forthcoming work on the extinct flightless birds of the Mauritius and 

 neighbouring isles, which Mr. Strickland is about to publish in con- 

 junction with Dr. Melville. 



With regard to the natural group or family of birds to which the 

 Dinornis, with its adze -like bill and crocodiloid cranium, may be re- 

 ferable, the author pointed out several marks of resemblance in the 

 skeleton of the Bustard to the Dinornis, which are not presented by 

 the skeletons of the true Struthionidce. But he also dwelt upon the 

 peculiar characters of the Dinornis, distinguishing it from the Otidce, 

 and indicating it to form a distinct family- type in the order of 

 Grallcs. 



With regard to the peculiar form of beak in Dinornis, reference 

 was made to the deductions in the former memoirs, •' from the un- 

 usual strength of the neck, " that the Dinornis would be found to 

 have a beak applicable " to a more laborious task than the mere 

 plucking of seeds, fruits or herbage ;" and that " the robust propor- 

 tions of the cervical vertebras, especially of their spinous processes, 

 may have been the foundation of those forces by which the beak was 

 associated with the feet in the labour of dislodging* the farinaceous 

 roots of the ferns that grow in characteristic abundance in New 

 Zealand." 



For this labour the beak of the Dinornis, formed after the model 

 of the adze or pick- axe, seems peculiarly adapted, and the singular 

 development in both breadth and depth of the occipital part of the 



