162 PROFESSOR OWEN ON THE GENUS DINORNIS. 
The under surface of the tenth cervical, 2b. C 10, is widely grooved, with the hyp- 
apophysial tubercles deepening the fore part of the sides of the groove. Slightly con- 
verging ridges from the upper part of the posterior zygapophyses represent the neural 
spine. 
‘These ridges converge as they advance upon the neural arch, in the ninth, eighth, 
seventh, sixth, and fifth cervicals, in which a low tuberosity on the fore part of each 
ridge represents the divided neural spine. The under surface of the centrum becomes 
flatter in the above vertebrze: the hypapophyses are represented by a tubercle on the 
lower part of each parapophysis. 
In the fourth cervical, ib. C4, the pair of tubercles representing the neural spine are 
longer: in the third cervical they are closer together: in the second they have coalesced 
to form a single spine, with a deep fossa at its back part: in the atlas, 2b. 1, the neural 
spine is obsolete. 
The hypapophysis in the third cervical is a single median ridge, as it is also in the 
axis, or second vertebra: in the atlas it is absent. The hind surface of the body of the 
atlas is convex, a little hollowed above to receive the odontoid process: the lateral 
‘vertebral’ canals are defined each by a slender vertical bar of bone. The under surface 
is produced into a pair of short tubercles at its hind margin and at its front margin ; 
and they project respectively backwards and forwards, not downwards as hypapophyses. 
The deep anterior cup, which receives the single occipital condyle, is notched at the 
middle of its upper part. The neural arch expands beyond the breadth of the centrum, 
and developes only the posterior pair of zygapophyses. 
The pelvis of the Dinornis elephantopus (Pl. XLVI. S 63, 64) is one foot nine inches 
in length, contrasting extraordinarily with the size of the skull. 
Six of the anterior sacral vertebree have parapophyses with the ribs confluent with 
them, save in the first: beyond the second vertebra the ribs simply abut against the 
_ilium, with which they are confluent. 
The ischium, 63, and pubis, 64, which coalesce with the ilium to form the acetabu- 
lum, do not again unite with each other: the notch at the under and fore part of the 
ischium opens into the long interspace between the two posteriorly extended bones. 
This part of the pubis, 64, is straight and styliform, 84 inches in length; slightly 
expanded, to a breadth of 14 lines, near the end ; flattened externally, convex internally, 
so as to offer a subtrihedral transverse section. The ischium, 63, with an upper and 
lower notch, having smooth and thick rounded borders, near the acetabulum, expands 
gradually, and is flattened, into a plate of about three inches of vertical depth, with a 
truncate termination. 
Nine caudal vertebra, of a transversely subquadrate form, with a contracted neural 
canal, surmounted by a low transversely extended arch supporting a pair of tubercles, 
represent the basis of the short tail of the Dinornis. 
The last of these vertebre is as small and simple as in other large birds devoid of the 
power of flight; showing nothing of that characteristic modification of the terminal 
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