776 
MAMMALIA. 
position by an elastic ligament, and is in this way protected from 
wear. 
protruded. 
When the animal straightens the phalanges, the claws are 
4 
(1) ZLUROIDEA, 
| e.g. cat, civet, hyzena. 
(2) CYNOIDEA, 
e.g. dog, fox, wolf, jackal. 
(3) ARCTOIDEA, 
eg. bear, otter, 
| Digitigrade. 
. tgs 3131 
Typical dentition, are 
The tympanic bulla is 
much dilated, 
rounded, and _ thin- 
walled, and is divided 
into two chambers 
by an internal septum 
(exceptin Hyzenidz). 
The paroccipital pro- 
cess of the exocci- 
pital is applied to the 
hinder part of the 
tympanic bulla, 
The czecum is small, 
rarely absent. 
Digitigrade, 
Typical dentition, an 
The tympanic bulla is 
dilated, but the in- 
ternal septum is 
rudimentary. 
The paroccipital pro- 
cess is in contact 
with the bulla, but 
it is prominent. 
The czecum is some- 
times short and 
simple, sometimes 
long and peculiarly 
folded, 
Plantigrade or sub- 
plantigrade. 
Typical dentition, 2*47. 
ae "3143 
The tympanic bulla is 
often depressed, and 
there is no hint of an 
internal septum. 
The paroccipital pro- 
cess is quite apart 
from the bulla. 
The czecum is absent. 
Digitigrade animals walk on their toes only; plantigrade forms res 
the whole sole of the foot on the ground; but between these condition 
there are all possible gradations. 
Many Carnivores are sub-plantigrade 
often when at rest applying the whole of the sole to the ground, br 
keeping the heel raised to a greater or less extent when walking. 
(1) ZELUROIDEA—Cat-like Carnivores 
Family Felid, including the most specialised forms. 
The canine 
are large, the molars are reduced to ‘, the carnassials are th 
last premolars above (with a three-lobed blade), and th 
molars beneath (with a two-lobed blade). 
The tuberculate 
upper molars are very small, and of little if any use i 
mastication. 
The skull is generally rounded, the zygomat' 
arches are wide and strong, and the tympanic bulle are Jarg 
and smooth. The limbs are digitigrade, the claws retractile 
