MAMMALIA. 525 
Keeping these points in mind, we may glance at the 
anatomy of the two types. 
Placing the two skulls before us, we note their features 
in common as follows:—In each the incisor teeth are 
small and pointed and are never more than 3, a distinc- 
tion from Polyprotodontia ; the canines are long, powerful 
and pointed ; and the premolars and molars have sharp- 
edged cusps, with an absence of the flat grinding -surfaces 
seen in the herbivorous types. In both there is a specially 
large cusped tooth in upper and lower jaw which is called 
the ‘‘carnassial” tooth, usually said to be used for breaking 
slippery bones. The. glenoid cavity of the squamosal is a 
Fig. 362,—LaTERAL View or Lion’s SKULL x 4. (Ad nat.) 
Canine Tooth. 
Zygomatic Arch. Auditory Bulla. 
Carnassial Tooth, : ===} Postglenoid Process. 
transverse groove, and into this there fits the cylindrical 
condyle of the mandible. Owing to this arrangement the 
mandible can only move in a perpendicular plane. Imme- 
diately behind the glenoid cavity is a wide process of the 
squamosal, called the postglenoid process, which prevents 
all backward horizontal motion of the mandible. 
On the cranial surface there are at least two large bony 
crests—the sagittal crest along the middle dorsal line and 
the occipital crest from side to side at the junction of 
parietals and occipitals. These form the surfaces of origin 
for the large jaw-muscles (¢emporalis) which pass down in 
