608 CARNIVORA 
that it is on the whole advisable to regard them as representing 
a distinet suborder of Carnivora. In the strong development of the 
canines ‘Fig. 273: they are distinguished irom the modern Insect- 
ivora: and chey also differ from the latter and resemble the true 
Carniveres in the form of the incisors. the second one in the lower 
jaw (when three are present) being thrust up above the level of the 
other two in the manner obtaiming in mest of the modern Carni- 
vora. Some of the most generasised forms included in the present 
group approximate sc closely to the Condylarthrous Ungulates as 
to indicate that both c<roups have probably had a common orizin. 
he Crecdonta as a whole are characterised by the small size 
of the brain, the absence of a single differentiated carnassial tooth, 
and the triangular form or secant character of their upper molars. 
In the carpus the scaphoid and lunar were usually distinct ; the 
femur has a third trochanter; the upper or tibial surface cf the 
astragalus usually wants the zroove found in modern Carniroves : 
and the feet were plantigrade. The curicus resemblance of che 
molars of many of these forms to those of the Marsupials may 
indicate a genetic relationship between the two groups: but, on the 
other hand. the presence of a full set of milk-teeth and the absence 
of palatal vacuities. or of an inflection <i the angle of the mandible. 
sharply distinguishes them from that order. Space permits of a 
notice only of the more interesting forms. 
AHyenodentidz.—This iamily is taken to include some of the 
more specialised types. such as the European and American 
Hucaodon and Oshyrna and the European Pteredei. In Hyenedon 
Fig. 2¢s) the dental formula is i =. » 2. p 4. m 2: the fourth 
premolar above and the first true molar below being formed upon 
the ~ carnassial” plan, tut the teeth behind these, instead of being 
taberculated as in all existing Carnivora, repeat the characters of 
the carnassial. and also increase in size, especially in the lower jaw. 
trom before backwards. The last lower molar differs from the 
two preceding teeth. and is very like the carnassial of Felis, The 
scaphoid and lunar of the carpus were fused tozether. Some species, 
as H. lepiorhynchus, were as large as a Wolf, while cthers did not 
exceed a Fox in size. Pferedin is readily distinguished by having 
wv 3, bv the larger size of the inner tubereles of the upper molars, 
and the similarity in the form of the three lower molars. In some 
species there were only two upper incisors. and the first lower pre- 
molar may be wanting. Chyrna is a specialised form with i =. 
¢ fy; P 4, m 2, and a very long mandibular svmphrsis. 
Provirerridt.—The European and American genus Prorirerra 
(Cynchyriiedan or Supoluphus) may be regarded as representing a 
second family. The dental formula in this genus is the typical i 3, 
cf. p 4. m 3, the upper molars have a large inner tubercle, while 
the lower molars are differentiated into a blade and talon, the 
