PKTAUUISTA. 
851 
skull I noticed a minute tootli in the same part. The single 
premolar on each side is placed close to the true molars, com¬ 
pressed in front, and expanded behind; a small anterior 
'tubercle is separated from the body of the tooth by a slight 
transverse incision. The true molars resemble those of the 
upper jaw, excepting that they are rather narrower, and the 
last tooth has four, instead of three, cusps. The skull of 
Pet . tag nano ides differs from the skulls of the species of the 
next section, in being smaller in proportion to the bulk of the 
animal, in having the zygomatic arches stronger, and flattened 
at die sides, in being deeply concave, and much contracted 
between the orbits, instead of flat, and in having the palate 
deeply emarginated behind. The nasal bone3 are much 
shorter. The toes of the fore foot are nearly equal in length, 
if we except the inner toe, which is distinctly shorter than the 
rest; they are provided with large, curved, and compressed 
claws, as are the toes of the hind feet, with the exception of 
the thumb, which, as usual, is naifless. The second and 
third of the hind toes are joined to the extremity, and the 
tliird is joined to the fourth for about half its length. The 
hands and feet are naked beneath. The Petauri, like the 
true Phalangers, are nocturnal, and hide themselves during 
the day in the hollows of trees. 
VOL. i 
