3-1 tf 
TAHSirES KOSTHATUS. 
skull, tibia and fibula, and the radius) have hitherto been 
noticed. 
The skull is proportionately large, being about equal to half 
the body in length, and i3 remarkable for the thinness and 
semi-transparency of the bones of which it is composed, 
the long and tapering facial portion, and the short and 
slender zygomatic arch, and consequently the small size of 
the fossa, of which it forms the outer boundary. Viewing 
the under surface of the skull, the great extent of the audi¬ 
tory chamber, and the imperfect condition of the palate, are 
also striking. 
The cranial portion of the skull occupies rather more than one 
third of the entire length, approaches to a spherical form, 
and presents a smooth surface. On the occiput scarcely 
any trace of a crest is perceptible, and the sutures which, in 
most Marsupials, mark the boundaries of the separate bones 
of which it is composed, are here obliterated, but all the 
other sutures of the crauium are distinct : the occipital 
opening is large. The interparietal bone is very large, and 
transverse ; the parietal bones are also large, whilst the 
frontal bones are rather small, and considerably contracted 
between the orbits. The lachrymal bones are tolerably large, 
and present the usual perforation. The zygomatic arch is 
extremely slender, and short, being in length equal to one- 
fifth of that of the skull; it is composed almost entirely of 
the malar hone, which sends up a small post-orhital process. 
The glenoid cavity is very small. The nasal bones are long, 
narrow in front, and much expanded behind. The large ear 
chamber presents an anterior and a posterior convex swelling, 
of which the foremost is the larger, and is formed partly by 
the sphenoid ala, and partly by the squamous portion of the 
temporal bone ; the hinder bulb, which is more convex, is 
due to the petrous and mastoid elements of the temporal 
bone. I cannot trace the tympanic bone. The palate is 
strongly concave in the trausverse direction; presents two 
long and narrow incisive openings, and two posterior open¬ 
ings, which are also narrow. The channel on the back part 
