OF THE NUBIAN GIRAFFE. 235 
and female Cape Giraffe, and of the skeletons and skulls of a male and female Nubian 
Giraffe, rather more than half-grown, I have only a few additional observations to offer, 
chiefly in relation to the alleged existence of a third distinct bony nucleus, forming the 
anterior mesial protuberance or horn. 
The part of the skull to which the elastic ligament is attached, is raised considerably 
above the roof of the cranial cavity by the extension backwards of large sinuses, or air- 
cells as far as the occiput. The sinuses commence above the middle of the nasal 
cavity, and increase in depth .and width to beneath the base of the horns, where their 
vertical extent equals that of the cerebral cavity itself. The exterior table of the skull, 
thus widely separated from the vitreous table, is supported by stout bony partitions, 
extended chiefly in the transverse direction, and with an oblique and wavy course. 
Two of the most remarkable of these bony walls are placed at the front and back part 
of the base of the horns, intercepting a large sinus immediately over the middle of the 
cranial cavity, and dividing it from a smaller sinus which covers the anterior part of 
the cranial cavity, and from a third and larger one behind. The sphenoidal sinuses are 
of a large size. (Pl. XL.) 
The nasal cavity occupies the two anterior thirds of the skull, and the ossa spongiosa 
are proportionally developed. The condyles of the occiput are remarkable for their 
extent in the vertical direction ; it is this structure which enables the Giraffe to raise 
the head into a line with the neck, and even to bend it a little way back upon the 
neck. This action I have often witnessed in the living animal. 
In the adult male Cape Giraffe the only appearance of the distinctness of the anterior 
protuberance is due to some irregular vascular grooves at the circumference of its 
base ; but similar grooves are aiso visible in the skull of the female ; anda section of the 
skull, taken through the middle of the frontal protuberance in the male, shows that it 
is formed by the thickening and elevation of the anterior extremities of the frontal 
and the contiguous extremities of the nasal bones. 
In the male Nubian Giraffes, which had attained nearly two-thirds of their full stature, 
the posterior horns, like other bony epiphyses, were less firmly attached to the skull 
than they were in the full-grown Cape Giraffes, and they became detached from the 
frontal and parietal bones after a short maceration. Now if the anterior protuberance 
had been formed by a similar separate ossification, this would undoubtedly have been 
demonstrated in a similar manner ; it, however, consisted only of a partial elevation of 
the frontal and nasal bones, as in the adult Cape Giraffe. 
The two posterior or true horns are not supported exclusively by an enlarged frontal 
bone, but rest each upon the coronal suture which traverses precisely the middle of the 
expanded base of the horn-shaped epiphyses. I have noticed the same position of the 
horns in the skull of an adult female Cape Giraffe, in which the two frontals are 
distinct, and joined by a well-marked suture continued along the posterior two-thirds 
of the frontal protuberance, or as far as the nasal bones. The sagittal suture is also 
