TRANSACTIONS 



OP 



THE ZOOLOGICAL SOCIETY 

 OF LONDON. 



I. On Dinomis (Part XXV.) : containing a Description of the Sternum of Dinornis 

 elephantopus. By Sir Kichard Owen, E.C.B., F.R.S., F.Z.S., &c. 



Received March 6th, 1884, read March 18th, 1884. 



[Plate 1.] 



IN 1868 I received an incomplete sternum of Dinornis elephantopus, wanting the 

 anterior border with the costal processes. As, however, the specimen, then unique, 

 showed modifications of breadth to length contrasting with those of a sternum of 

 Dinornis rheides, it was described and figured in the under-cited volume 1 . 



I have now been favoured, through the kindness of John Enys, Esq., with a specimen 

 of a sternum of the same species of Dinornis, found on his estate at Christchurch, New 

 Zealand, with the anterior border entire, and lacking only the ends of the long " lateral 

 processes." 



The breadth of the anterior border is here shown to be, in a straight line, 9^- inches ; 

 but following the curvature, which is convex outwardly, it measures 10 inches 6 lines. 



This border is smoothly convex, about \ inch in breadth, bent inwards 2 for an extent 

 of more than an inch. The convexity thus formed changes gradually to a concavity 

 towards each lateral border of the bone, separating the base of the " costal process," b d, 

 from the beginning of the " costal tract," m, c. 



The costal process, d, is subcompressed, \\ inch in length, 1 inch 4 lines in breadth 

 at its obtuse free border ; a smooth, oblong, flatfish, rather rough surface, 9 lines by 3 



1 Trans. Zool. Soc. vol. vii. part ii. (1870), p. 115, plate vii. 



' Terms of aspect and position relate to the skeleton of the bird in the standing posture. 



vol. xii.— part i. No. 1. — February, 1886. a 



