SIWALIK AND NARBADA CARNIVORA. 
67—244 
closely approximated : pm. 2 and pm. 3 are more trenchant and compressed than in 
Cynodictis, and the former has no talons : all the premolars are more elongated than 
in Gynodon. The upper carnassial has a well-developed inner tubercle ; placed more 
anteriorly than in Cynodictis, and more distinct than in Gynodon. The true molars 
are larger than in the latter, and resemble those of Cynodictis. The ascending ramus 
of the mandible is extremely different from that of Gynodon and Cynodictis , and is 
said to resemble that of Lutra : m. i has a much shorter tubercular portion : pm. 4 has 
a hind talon-cusp, but is less complex than in Ganis. 
The genus Amphicyon , 1 Lartet, is distinguished from all its allies, except Otocyon , 
by the presence of m. 3 ; the number of the cheek-teeth being pm. j, m. -§ : m. 3 is, 
however, normally small, and M. Filhol has shown 2 that in one species ( A . ambiguus ) 
this tooth is extremely minute, and occasionally absent. The presence of this tooth 
probably indicates that the dogs and bears originally descended from a stock in 
which the full number of the eutheroid dentition was present. In noticing this 
genus Prof. Huxley 3 remarks that “in the shortness of pm. 4 4 relatively to m. 1 , the 
large size of m. 2 relatively to m. 1 , and of m. 2 relatively to m. 1, the dentition of 
Amphicyon repeats the general characters of that of Cynodictis .” In certain specimens 
of A . ambiguus , however, 5 pm. 4 is relatively much longer in proportion to m. 1 than 
in the latter genus — the proportions in the individual referred to being 1*4: TO; 
indicating a megalocreodont character. From measurements given by M. Filliol 6 it 
appears, however, that megalocreodontism may exist with meionocreodontism in 
different individuals referred to the same species ; apparently indicating that certain 
individuals had attained in this respect a specialization as great as that of the most 
specialized modern dogs ; while others ( A . lemanensis 7 ) had not advanced beyond the 
Cynodictis stage. The upper carnassial is very like that of Canis, but has a larger, though 
similarly placed, external tubercle : the inner cusp of the blade of m. 1 is larger than in 
Canis, and the ‘ cusp-line ’ less oblique : the upper true molars are intermediate between 
those of Cynodictis and Canis, but on the whole nearer those of the latter. The 
ursoid characters of the limbs and some parts of the skulls have been already alluded 
to. On the whole Amphicyon appears to be a generalized genus, somewhat more 
advanced in the direction of the bears and modern dogs than Cynodictis , and of 
which some species had attained a considerable dental specialization. 
From Amphicyon and Cynodictis the transition is very gradual to Cephalogale and 
Dinocyon, the latter of which, as previously mentioned, 8 cannot be distinguished by 
any characters of more than generic value from the hysenarctoid bears. In the 
former 9 the number of the cheek-teeth is the same as in Canis : the earlier premolars 
have simple compressed crowns : m. 1 has the inner cusp of the blade small, but the 
1 Pseudocyoti, Lartet, Cynelos, Jourdan, Agnotlierium, Kaup. 
2 “ Notes sur quelques Mammiferes Fossiles, etc.,” p. 76. 3 op. cit., p. 282. 4 Misprinted pm. 4. 
5 Filliol, “ Phosphorites du Quercy,” figs. 23-6 (A. ambiguus). 
6 “ Notes sur quelques Mammiferes, Foss., etc.,” p. 26. 7 Ibid, pi. I. 8 Vide, p. 202. 
9 Filhol, “ Notes sur quelques Mam. Foss., etc.,” pi. II. 
