Hutton. — The Axial Skeleton in the Dinornithidce. 161 



A very good series of woodcuts of vertebrae are given by- 

 Owen in Trans. Zool. Soc, vol. x., pp. 152-170, and in 

 " Extinct Birds of New Zealand," pp. 396-414. These, which 

 are referred to Dinomis maximus, really belong to Pachyomis, 

 as has already been pointed out by Mr. Lydekker. A correc- 

 tion in the numbers of these vertebra? will be useful : — 



Rings of the Trachea. — Two types of ossified tracheal rings 

 are found with moa-bones : (1) The hoop-like rings of Lydek- 

 ker, which are slender, smooth, and often elliptical in shape ; 

 (2) the tube-like rings of Lydekker, which are thick, rough, 

 deep, and circular in section. These two types have always 

 been considered as generically distinct, but such is not the 

 case. In a skeleton of Euryapteryx ponderosa, found by Mr. 

 B. S. Booth in the central district of Otago, the trachea was 

 nearly complete, and it had hoop-like rings near the head and 

 tube-like rings near the sternum, one set gradually passing 

 into the other about the middle of its length. This was 

 probably the same in all the moas, as some of the tube-like 

 rings are very small. 



In the following remarks I shall treat all the free vertebrae 

 which have ribs as thoracic — that is, from No. 22 to No. 28. 

 Those in front of them are cervical ; those behind them belong 

 to the pelvis. 



Genus DINOBNIS, Owen (1843). 



Type — D. robustus, Owen. 



Figures. — Atlas, Owen, Trans. Zool. Soc, vol. v., pi. 53, 

 figs. 4-6, and Ext. Birds of N.Z., pi. 62. Axis, Owen, Trans. 

 Zool. Soc, vol. x., p. 150, figs. 4-7, and Ext. Birds, p. 394. 

 Cervical vertebra, Owen, Trans. Zool. Soc, vol. hi., pi. 40, 

 and Ext. Birds, pi. 32. Lydekker, Fossil Birds, Brit. Mus., 

 p. 247, fig. 59. Pelvis, Mivart, Trans. Zool. Soc, vol. x., 

 p. 43, figs. 42, 43. Sternum, Owen, Trans. Zool. Soc, vol. x., 

 pi. 32, and Ext. Birds, pi. 98. Lydekker, I.e., p. 222, fig. 56. 



Cervical Vertebra. 



In the axis the odontoid process is long, tapering, and 

 slightly rounded. The pre-axial articulating surface moderate, 

 the height less than the breadth. The neural spine is remark- 

 ably high and thick. The anterior cervicals — 2 to 6 — are short 

 and broad. In No. 5 the length is three-quarters of the 

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