MACRO POD I I)jE. 
A5 
this little animal forms the type of Mr. Gould’s genus Lag or- 
c/testes ; but even in this little section I find the muflle less 
perfectly clothed in a second and nearly allied species. 
Lastly, among the Kongnroo-rnts, in which the nmllle is de¬ 
scribed us " lmld,” is one species ( Bettongia rufesccns) in 
which that part is almost entirely covered with small hairs. 
The presence or absence of canine teeth is dwelt upon as 
. furnishing a distinguishing character of the Kangaroos and 
Kangaroo-rats; several species of Knugnroos, however, have 
canine teeth even when adult, and in all probability all pos¬ 
sess them in a very rudimentary condition when young: they 
have been noticed by Professor Owen in the young Mac raj ms 
gigantca*. In two adult skulls of different species of 
Ilahnaturux in the British Museum (//. Ua la bat as and 
II. Thetidi *), I find the sockets of these teeth remaining. 
The canines, however, cannot be regarded as functional teeth 
in the Kangaroos, where they are always very small, whilst in 
the Hgpsiprgmni (or Kangaroo-rats) they lire tolerably well 
developed. 
In the structure of the incisor teeth of the upper jaw, the 
various species of Macropodida differ considerably; the 
principal modifications which I have noticed have presented 
themselves in the Macropus giganteus, M. Benncttii , M. 
T/tel id is, M. Itporoide.s , and in the genus Hgpsiprgmnns , 
and are pointed out in tlieir proper places. 
With regard to the premolars, and true molars, there are but 
two striking modifications of structure, and theso are ex¬ 
hibited, on the one hand, in the Kangaroos proper, and, on 
the other, in the Kangaroo-rats; in these animals there ore 
equally marked modifications in the structure of the cranium, 
and some less striking peculiarities in the extremities. I may 
add, that in the true Kangaroos, which are, I believe, the 
only Marsupials which are not of nocturnal habits, there are 
always distinct eyelashes to the eyes, springing from the eye- 
