MAMMALIA. 
(Peramelide). It is, 
however, confined to 
these and not found in 
the Lutheria. 
The tibia and fibula 
are very long and the 
femur is short but 
powerful. The pelvis 
shows well the large 
epipubic bones, found 
not only in Metatheria 
but in Prototheria. 
The foot of the 
kangaroo is modified 
for rapid locomotion, 
mainly by jumping, and 
the toes are  corres- 
pondingly reduced. In 
501 
Fig. 345.—PELVic GIRDLE OF THE 
KANGAROO x f. 
(dd nat.) 
Epipubic. ~~ 
Obturater 
Foramen.., 
Fig. 346.—HInp-roor or KANGAROO 
x 3. (Ad nat.) 
Calcaneum, 
Metatarsals. 
Note the absence of the hallux, the large fourth 
toe and the syndactylic second and third. 
some. respects it is not 
unlike that of the two- 
toed ostrich. The ves- 
tigial second and third 
toes take no part in 
locomotion but may be 
useful for scratching the 
fur. 
Orver I. 
Polyprotodontia, 
The Polyprotodontia 
are so-called because 
they have a large num- 
ber of front or incisor 
teeth. There are always 
more than three pairs 
of incisors in the upper 
jaw, usually four or five; 
hence the skull of a 
polyprotodont can, apart 
from other metatherian 
