OF THE NUBIAN GIRAFFE. 237 
loped from the whole longitudinal extent of the superior arch, but has a very slight 
elevation. In the rest of the cervical vertebre the spinous processes are thin triangular 
lamine, in each of which the apex rises about an inch and a half from a longitudinally 
extended base resting upon the middle of the superior arch; the seventh spine is thicker, 
higher, and of less longitudinal extent than the preceding ones. Processes analogous to 
the inferior transverse processes in the Crocodile, extend downwards and outwards from 
the lower part of the anterior extremity of each of the cervical vertebre, except the atlas 
and dentata ; they are, however, of much smaller size than the corresponding processes 
in the Camel: the superior transverse processes are represented by longitudinal ridges 
developed from the middle of the side of the posterior part of the body of the vertebre. 
The perforations for the vertebral artery are large, and are present in the seventh, as 
well as the rest of the cervical vertebre; they are situated above the transverse processes, 
in the side of the body of the vertebre at the base of the superior lamine. Although in 
this position of the arterial foramina, owing to the feeble development of the trans- 
verse processes, the Giraffe differs somewhat from the other horned Ruminants, yet the 
structure of the cervical segment of the vertebral column is essentially the same as in 
them, and is very different from that in the long-necked Camelide. 
In the cervical vertebre of the Camel and Llama the transverse processes are more 
developed than in the Giraffe, but, as in that animal, are not situated in the same per- 
pendicular plane on the sides of the vertebre, and do not intercept a space, as in most 
other Mammalia, for the protection of the vertebral arteries. These important vessels, 
however, instead of perforating the sides of the body of the vertebre, as in the Giraffe, 
pass through canals in the superior lamine, of which the orifices are entirely concealed 
from external view. From the seventh or sixth to the second cervical vertebre inclusive, 
both in the Auchenie and Cameli, the vertebral arteries enter the vertebral canal itself 
along with the spinal chord at the posterior aperture in each vertebra ; they run forwards 
on the outside of the dura mater of the chord, between it and the vertebral arch, and 
when they have thus traversed about two-thirds of the spinal canal, they perforate sepa- 
rately the base of the superior vertebral Jamine, and emerge directly beneath the ante- 
rior oblique or articulating processes, whence they are continued along with the spinal 
chord into the vertebral canal of the succeeding vertebra, perforating the sides of the 
anterior part of the superior arch in like manner, and so on through all the cervical 
vertebre till they reach the atlas. Ina very remarkable extinct Pachydermatous animal, 
(Macrauchenia), whose fossil remains were discovered by Mr. Darwin at Port St. Julian, 
Patagonia, and which had cervical vertebre as long as those of the Giraffe, I found the 
same peculiar disposition of the canals for the vertebral arteries as in the Auchenie and 
Cameli. 
In viewing the vertebral column of the Giraffe from above, we perceive that the cer- 
vical vertebre present the broadest as well as the longest bodies ; of these the third and - 
fourth are the narrowest and longest, the rest gradually increase in breadth and diminish 
VOL. I1.—PART III- 21 
