Cu. I.] OF THE DODO. 8] 
accompanying vessels, is eight lines distant from the foramen opticum, in a direction forwards and upwards, 
and midway between it and the ant-orbital process. Its form is irregularly transversely ovate ; a ventricose 
projection on the left side, encroaches on its area inferiorly. The posterior expanded border of the inferior 
ethmoidal ala, is three lines and a half broad. The prefronto-ethmoidal fissure is obliterated; a narrow, 
tripartite chink, slightly wider in the centre, alone remaining; the inner branch of which probably corres- 
ponds to the notch between the turbinated and inferior ale, the evasation of the latter to form the large 
olfactory fossa being the cause of the disappearance of this fissure, which in other birds transmits the 
superior diverticulum of the subocular smus; the upper indicates the union of the prefrontal to the turbi- 
nated ala; from its extremity an interrupted groove, more distinct on the right side, is directed downwards 
and outwards at an acute angle, to the upper margin of the lacrymal groove, defining the antorbital process 
as it runs along the outer margin of the body of the prefrontal. 
The tumid prefrontal coalesces below with the inferior ala, and is three lines and two-thirds wide; its 
broad outer convex surface, beneath the antorbital process, presents the lacrymal groove, more depressed at 
its lower margin; it runs forward, inclining inwards, to the outer margin of the olfactory fossa, and is 
eight lines in length, and three and a half broad; in the immer part of its course, it rests on a quadrate 
process of the prefrontal, which projects beyond the level of the anterior margin, and comes into contact 
with the convexity of the turbinated ala; this projection is separated by a notch, from the prominent inner 
angle of the body of the prefrontal above, and below from its inferior extremity ; which is slightly flattened 
and roughened opposite the zygoma, with which it would probably come into contact, in the great downward 
flexion of the upper mandible. The ant-orbital process is thick and rough externally, and contracts in its 
anterior moiety, into a narrow style, whose apex is at the upper border of the lacrymal groove. From the 
supra-orbital notch a deep capillary fissure, with small lateral offsets, passes backwards and imwards, on the roof 
of the orbit for six lines ; it probably lodged a small branch derived from a cutaneous artery. The superciliary 
margin is perforated about six lines in front of the post-orbital process, by two small foramina on the left 
side, but is notched on the right for the transmission of the supra-orbital arteries and veins to the scalp ; 
internally they correspond to a groove running half an inch in front of, and parallel to, the posterior border 
of the orbit ; it winds round a tumid projection of the diploé of the ala-sphenoid a little above the foramen 
opticum, which it enters, grooving its roof, and disappearing as it curves backwards. A second groove, for 
the nasal vessels, runs backwards and upwards from the ant-orbital foramen, to join the supra-orbital furrow 
above the prominence just mentioned. Numerous small apertures are seen along the course of these 
channels ; a faint vascular groove runs from the prefronto-ethmoidal fissure to the centre of the nasal 
one ; between the latter and the foramen opticum, and bounded laterally by the peculiar pneumatic bulle, is a 
quadrate space, variously marked by vascular impressions. 
The temporal fossa descends obliquely forwards, slopmg mwards, and terminates inferiorly at a deep 
digital cavity, impressing the ali-sphenoid behind the optic foramen. It opens superiorly by the small narrow 
oblong temporal notch, five ines in depth, and three and a half in breadth ; bounded in front by the short, 
thick, post-orbital process, slightly recurved at the apex, and behind by the post-temporal plate of the mas- 
toid. The small crotophyte impression occupies the temporal gorge, and extends outwards, as the latter is 
broadly rounded off mto the upper facet, in the form of a crescent, whose limbs extend on the triangular 
surface of the post-orbital process, and on the quadrantal post-temporal plate, which is traversed by a slight 
chord-like ridge. The internal temporal impression has the figure of a right-angled triangle; below, a 
narrow smooth tract separates its base from the surface for the MW. Levator ossis quadrati; the undulated 
hypothenuse ascends forwards to the root of the post-orbital process, its upper third being separated by a faint 
ridge from the external impression ; its surface subsides, anteriorly, about a line beneath the smooth and 
