ANATOMY OF BALDEN OPTEEA EOSTEATA. 
213 
nearly flat, corresponding in shape to the superior surface of the external angular process 
of the superior maxilla, and its superior surface, which was rough and slightly convex 
internally, underlay the anterior portion of the orbital plate of the frontal, where the 
lachrymal was wedged in between these two bones. 
The malar or zygomatic bone was slender and somewhat rib-like or falcate ; it formed 
the inferior boundary of the orbit, and was broader behind than in front ; its anterior 
border articulated with the external orbital or zygomatic spine of the superior maxilla ; 
its wider or posterior extremity was flattened, and fitted in between the anterior border 
of the glenoid process of the squamous bone and the posterior angular process of the 
frontal, where a digital depression existed for the reception of the former. In outline 
the bone presented a curve which was much sharper in front than behind. 
The external aperture of the bony orbit which was formed by the frontal, squamous, 
malar, and lachrymal bones, measured 4^ inches in length by 3^ in breadth. 
The cervical vertebrae were seven in number. 
The first, or atlas, was an irregular bony ring, somewhat oval in outline, 5f inches 
in height, having two surfaces, the anterior of which presented two lateral, reniform, 
shallow concavities, for the reception of the condyles of the occipital bone ; these were 
separated from each other by a shallow groove with slightly elevated edges ; this in the 
recent state was occupied by the anterior atlanto-occipital ligament. The neural arch 
was angular in shape, with its apex terminating in a very short neural spine, directed 
backwards ; the neurapophyses were separated from the articular surfaces by a deep 
semicircular channel for the transmission of the suboccipital artery. The transverse 
processes, short and stout, stood out on each side about the centre of the transverse axis 
of the bone external to the articular depressions, their upper edges being directed forwards 
and upwards ; the entire width of the vertebra across these processes was 7f inches. 
The posterior surface presented two reniform convex articular facets, which corre- 
sponded in outline with the articular cavities on the anterior aspect ; these articulated 
with corresponding depressions on the anterior surface of the axis, and were separated 
posteriorly from the neurapophyses by a very shallow groove or depression, for the 
transmission of the second pair of cervical nerves. The neurapophyses arched back- 
wards and coalesced to form a very rudimental neural spine. 
On each side of the external surface of this vertebra an oblique ridge ran backwards 
and upwards from the superior and external angle of the transverse process to a small 
tubercle (zygapopliysis) which overhung the groove that gave exit to the second cervical 
nerves. This ridge gave attachment to the rectus capitis lateralis. There was no ante- 
rior tubercle on the ventral aspect of the body of this bone. 
The second, or axis, consisted of a very narrow body irregularly elliptical in outline 
with two surfaces, the upper of which presented a central hemispherical elevation 
(odontoid process), and which, when the bone was placed in situ , occupied the anterior 
semicircular space between the articular facets of the atlas. This eminence was parti- 
ally separated from the body of the axis by a well-defined fissure, situated transversely in 
the posterior wall of the body of the vertebra, where the osseous incrustations or epi- 
