ROOM II. MOA OF NEW ZEALAND. Ill 



proportions of the largest species), is now restricted to the most 

 remarkable ornithic type hitherto observed either in a recent 

 or fossil state, and of which there is in the case before us the 

 only cranium and upper mandible that has been discovered. 



As the typical crania and many of the bones in this collec- 

 tion are figured and minutely described in Vol. III. of the 

 Zoological Transactions, I would refer the scientific observer 

 to the original memoirs, and confine myself to a concise com- 

 mentary on the anatomical characters of a few of the principal 

 specimens. 1 



Of the Dinornis there is a nearly perfect cranium, with the 

 upper mandible and portions of two other skulls, in Table-Case 

 1 6. This specimen is represented in profile (half the natural 

 size in linear dimensions) in Lign. 26 : and the occipital 

 region or hind part of the cranium in Lign. 27. 



Cranium of Dinornis. The cranium of the Dinornis, espe- 

 cially in the temporal and occipital regions, is wholly unlike 

 any hitherto observed in the class of Birds, and approaches 

 that of Reptiles. It is characterized by the nearly vertical 

 occipital plane, the elevated form and position of the foramen 

 magnum, the great development below the occipital con- 

 dyle, and the strong ridges which border the basi-occipitals, 

 and indicate an extraordinary power in the muscles that 

 moved the head. (See Lign. 27.) The temporal fossae are very 

 deep, and are strengthened by a prolongation of the mastoid 

 process, which is united to the frontal, and forms what may 

 be termed a lateral zygomatic arch. The tympanic bone has 

 two distinct cusps for articulation with the double condyle of 

 the os quadratum. 



In no bird is the extent of surface for the attachment of 

 muscles at the back of the head so great, or so strongly 

 marked by ridges and depressions, as in the Dinornis. The 

 extension of the occipital surface in breadth by the expansion 

 of the paroccipitals, (Lign. 27, 6. 6.) and downwards by the 

 thick wedge-shaped development and abrupt descent of the 

 basi-occipital sphenoidal area (Lign. 27, a. a.), and by its lateral 

 backwardly produced ridges, is altogether peculiar. The 

 nearest approach to this structure is observable in the large 



1 See Appendix C. Memoirs on the Dinornis, by Professor Owen. 



