99 
The following are comparative admeasurements of this vertebra, and a corresponding 
one of a full-grown Ostrich :— Dinornis. Struthio. 
In. Lin, In. Lin. 
Deppth « . 3. Ry es re ee ht, ed oe 2 0 
Depth of anterior articular sartaee 8 tt aie Phe 0 74 
Breadth, including costal articulations . . . 1 6 2 0 
From the lower margin of posterior articular scfice to 
the upper one of posterior oblique process 
bo 
1 1 8 
The spinous process of this vertebra is strong and square-shaped’, and shows, like 
the preceding dorsal, that there was no blending together of the spines, nor any union 
by continuous splint-like ossifications, as in many birds, and especially in those that 
fly. The dorsal region in the skeleton of the Dinornis, by the intervals separating the 
spinous processes, must have resembled that in the large existing Struthionide, and 
have differed from the same part in the Apteryx, in which the dorsal spines are con- 
tiguous though not confluent ; but the Dinornis surpassed all known birds in the thick- 
ness and squareness of its upright spinous processes. Of the length of these processes 
none of the five vertebra afford an exact idea, all being more or less fractured, 
The spinal canal is proportionally more contracted than in the Ostrich, or even in 
the Apteryx, where it is rather smaller than usual. This character in the Dinornis indi- 
cates, of course, a more slender spinal chord, in which respect it betrays a closer ap- 
proach to the Reptilia. We may associate, with such a condition of the spinal marrow, 
less delicate perception, and less energetic muscular action; and the vertebr thus 
confirm the induction from the texture of the femur, that the Dimornis was a more 
sluggish or less active bird than the Ostrich. 
CONCLUSION. 
Physiological indications of the nature and proportions of the Anterior or Pectoral 
Members. 
Had the Dinornis wings? To this question I was led to give a negative reply after 
the examination of the first fragment of that bird’s bone which came into my hands*. 
It has appeared strange and almost incredible to some, that the cancellous texture of 
the shaft of a thigh-bone should give, to speak mathematically, the presence or absence 
of wings. But if the negative had been premature and unfounded, a guess rather than 
a demonstration, its fallacy might have been exposed by the very next bone of a Dinor- 
nis transmitted from New Zealand. A bird of flight has as many wings as legs ; it has 
two humeri as well as two femora, two radii as well as two tibiz, two ulnze as well as 
| Pl, XVII, fig. 7- 
2 Absence of the organs of flight is the essential character of a Struthious bird, more especially of one 
“ heavier than the Ostrich.” 
02 
