Hutton. — The Axial Skeleton in the Dinomithid.ee. 165 



axial base of each neural ridge there is a saucer-shaped de- 

 pression which is sometimes pierced by a foramen under the 

 zygapophysial bridge. The faces of the post-zygapophyses 

 are more horizontal than in Dinornis. Hyperapophyses are 

 distinct on No. 18. The posterior cervicals — 19 to 21 — have 

 short, but comparatively narrow, centra on all. The neural 

 spiue is usually single on No. 21 only. The hypapophysis is 

 single on No. 19. The hyperapophyses are distinct in Nos. 19 

 and 20. Posterior pneumatic foramina are developed in all. 



Thoracic Vertebrae. 



Post-axial faces broad. In Nos. 22 and 23 the dorsal 

 margin is rather less than the height, while the ventral 

 margin is more than the height ; in all the others the sides 

 are parallel ; the breadth is about equal to the height in 24 

 and 25, and greater than the height in the others. The 

 anterior pneumatic foramen descends below the rib-facet in 

 27 and 28, but is often divided into dorsal and ventral portions 

 by a bony septum. In 26 it is large, and often reaches 

 slightly below the rib-facet, but is not divided ; in 24 and 23 

 it is often small or obsolete, but usually developed again on 

 No. 22. The posterior pneumatic foramen is generally well 

 developed on all. The hypapophysis in 22 and 23 is central ; 

 in 24 and 25 it is continuous the whole length of the cen- 

 trum, and is slightly notched in the middle in No. 25. 

 There is a small anterior tubercle in Nos. 26 to 28. The 

 transverse processes are long, especially in Nos. 25 and 26, 

 and rise slightly. The neural spine is much inclined for- 

 ward in No. 22 ; in the others it is long and compressed ; 

 straight or slightly curved forwards in 26 to 28. In these 

 three the neural spine is twice as long as the distance from 

 its base to the ventral margin of the centrum. The post- 

 zygapophyses rise rapidly, and their faces are narrowly oval ; 

 they form a right angle with each other, but the valley be- 

 tween them is shallow. The pre-zygapophyses are moderate, 

 slightly expanding distally. 



Pelvis. 

 Pre-acetabular portion of the ilia moderately deep, forming 

 a sharp dorsal ridge, which is curved axially. The centre of 

 the acetabulum is in the centre of the ilium. The ilia begin 

 to diverge at the anterior margins of the acetabula, and are 

 prolonged backwards rather beyond the centrum of No. 46, 

 making a broad pelvic disc : the angle of divergence is be- 

 tween 60° and 70°. The lateral surface of the post-acetabular 

 portion of the ilium slopes downwards and inwards, and 

 posteriorly projects as a sharp ridge below the vertebral 

 column. The ventral surfaces of the sacral vertebras are 



