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460 DENTAL ANATOMY.
In the third section the mandible possesses a strong inferior flange
upon each side to protect the powerful canines of the upper jaw, which
in some forms project far below the level of the symphysis. They are
therefore known as the " sabre-tooth division." In the hrst of these
genera, Dinidis (Fig. ^-11), the true molars are ^, the inferior sectorial
Fig. 24]
Skull of Dincitis Cyclops, one-half natural size (after Cope).
has a heel, and the true molar above is a moderately well-developed
tooth, as in the preceding genera. The genera Hoplojihoneus and Pogon-
odon carry dental specialization several steps further, while in Eusmilus
we have the highest point reached by any of this group, which is in
many respects superior to the living cats.
Cope, in commenting upon the dentition of this group, says : " It is
readily perceived that the genera above enumerated form an unusually
simple series, representing stages in the following modifications of parts :
(1) In the reduced number of molar teeth ; (2) in the enlarged size of
the superior canine teeth ; (3) in the diminished size of the inferior
canine teeth ; (4) in the conic form of the crowns of the incisors; (5)
in the addition of a cutting lobe to the anterior base of the superior
sectorial tooth ; (6) in the obliteration of the inner tubercle of the lower
sectorial, and (7) in the extinction of the heel of the same ; (8) in the
development of an inferior flange at the latero-anterior angle of the
front of the ramus of the hnver jaw ; (9) in the development of cutting
lobes upon the ])osterior border of the large premolar teeth
The succession of the genera above pointed out coincides with the order
of geologic time very nearly The relations of these genera are
very close, as they differ in many cases by the addition or subtraction
of a single tooth from each dental series. Tliese characters are not
even always constant in the same species, so that the evidence of
descent, so far as the genera are concerned, is conclusive. No fuller
genealogical series exists than that A\hich I have discovered among the
extinct cats."
The last family of the Ailuroidea is the Felidcp, in -svhich we meet
with the highest |)oint in specialization that has been reached in the flesh-
460 DENTAL ANATOMY.
In the third section the mandible possesses a strong inferior flange
upon each side to protect the powerful canines of the upper jaw, which
in some forms project far below the level of the symphysis. They are
therefore known as the " sabre-tooth division." In the hrst of these
genera, Dinidis (Fig. ^-11), the true molars are ^, the inferior sectorial
Fig. 24]
Skull of Dincitis Cyclops, one-half natural size (after Cope).
has a heel, and the true molar above is a moderately well-developed
tooth, as in the preceding genera. The genera Hoplojihoneus and Pogon-
odon carry dental specialization several steps further, while in Eusmilus
we have the highest point reached by any of this group, which is in
many respects superior to the living cats.
Cope, in commenting upon the dentition of this group, says : " It is
readily perceived that the genera above enumerated form an unusually
simple series, representing stages in the following modifications of parts :
(1) In the reduced number of molar teeth ; (2) in the enlarged size of
the superior canine teeth ; (3) in the diminished size of the inferior
canine teeth ; (4) in the conic form of the crowns of the incisors; (5)
in the addition of a cutting lobe to the anterior base of the superior
sectorial tooth ; (6) in the obliteration of the inner tubercle of the lower
sectorial, and (7) in the extinction of the heel of the same ; (8) in the
development of an inferior flange at the latero-anterior angle of the
front of the ramus of the hnver jaw ; (9) in the development of cutting
lobes upon the ])osterior border of the large premolar teeth
The succession of the genera above pointed out coincides with the order
of geologic time very nearly The relations of these genera are
very close, as they differ in many cases by the addition or subtraction
of a single tooth from each dental series. Tliese characters are not
even always constant in the same species, so that the evidence of
descent, so far as the genera are concerned, is conclusive. No fuller
genealogical series exists than that A\hich I have discovered among the
extinct cats."
The last family of the Ailuroidea is the Felidcp, in -svhich we meet
with the highest |)oint in specialization that has been reached in the flesh-
