498 CARNIVORA 
throughout the suborder, they are greatly modified in different 
genera. The upper carnassial is the most posterior of the teeth 
which have predecessors, and is therefore reckoned as the last 
premolar (p 4 of the typical dentition). It consists essentially of a 
more or less compressed blade supported on two roots and an inner 
tubercle supported by a distinct root (see Fig. 220). The blade 
when fully developed has three cusps or lobes (1, 2, and 3), but the 
anterior is always small, and often absent. The middle lobe is 
conical, high, and pointed; the posterior lobe has a compressed 
straight knife-like edge. The inner tubercle (4) varies very much 
Fic. 220.—Left upper carnassial teeth of Carnivora. I, Felis; II, Canis; III, Ursus. 
1, Anterior, 2, middle (paracone), and 3, posterior (metacone) cusp of blade; 4, inner tubercle 
(protocone) supported on distinct root; 5, inner cusp posterior in position, and without 
distinct root, characteristic of the Urside. 
in extent, but is generally placed near the anterior end of the 
blade, though sometimes it is median in position. In the Urside 
alone both the inner tubercle and root are wanting, and there is 
often a small internal and posterior cusp (5) without root. In this 
aberrant family also the carnassial is relatively to the other teeth 
much smaller than in the rest of the Carnivora. The lower 
carnassial (see Fig. 221) is the most anterior of the teeth without 
predecessors in the milk-series; it is therefore reckoned the first 
true molar (m 1). It has two roots supporting a crown, consisting 
when fully developed of a compressed bilobed blade (1 and 2), a 
heel, or talon (4), and an inner cusp (3). The lobes of the blade, 
of which the hinder (2) is the larger, are separated by a notch, 
generally prolonged into a linear fissure. In the most. specialised 
Carnivora, as the Felide (I), the blade alone is developed, both 
talon and inner cusp being absent or rudimentary. In others, as 
