241—64 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
These measurement show in the first place that in group A the cheek-teeth are 
relatively smaller than in the group B, so that the one may he termed microdont , and 
the other macrodont forms ; and they also show that while pm. 4 , m. 1 , and m. 1, m. 2 all 
become larger between G. zerda and G. argentatus , the increase is far greater on the 
part of pm. 4 than on that of m. 1 , and of m. 1 than on that of mTA 1 (See woodcut 
figure 8). The following table, calculated from Professor Huxley’s measurements, 
exhibits the proportionate length of pm. 4 to m. 1 (=1-0) in three species of 
microdonts, and three of macrodonts, viz . : — 
Canis zerda 
— littoralis 
— azarse 
— argentatus 
— lupus 
— vulpes 
1-19 \ 
1*23 | microdonts. 
1-26 ) 
1-39 \ 
1-4 > macrodonts. 
1-4 ) 
As this relationship is more available for palaeontological purposes than the 
relations of the teeth to the basicranial axis, it is proposed (as has been done with 
the mustelines and the bears) to term the forms with small carnassials meionocreodonts , 
and those with large carnassials megalocreodonts : it may be convenient to class with 
the latter all those forms in which the proportionate length of pm. 4 exceeds 1*34. 
The accompanying woodcut 
(fig. 8) exhibits the megalo- 
creodont character of C. 
argentatus , and the accom- 
panying diminution in size 
of m. 2 ; and m. 3. 
Regarding the structure 
of the carnassials, in the 
genus ( anis , in which the 
number of the cheek-teeth 
is normally pm. f- , m. f , 2 and 
Gy on ( Guon), in which the 
true molars are §, the upper 
carnassial ( pm. 4 ) consists of 
a distinct bilobed blade, with 
a relatively small tubercle 
(inner cusp) at its antero- 
internal angle. In Otocyon 3 
in which the number of the 
fit’ larger 
Fig. 8. The cheek-teeth of the recent Canis arg>ntatus (A, A'), 
and C. littoralis (B, B') : the former 'p> the latter f this 
arrangement makes the length of m - 1 the same in hoth, and 
consequently exhibits well the megalocreodont character of the 
former and the meionocreodont character of the latter, a b, 
a' b' cusp-lines: ^7§ in BA was absent, and is figured from 
another specimen. 
clieek-t,eeth is pm. f , m. [H], the dentition is microdont and meionocreodont, and the 
1 Quoted with some alterations from Prof. Huxley’ s memoir. 
2 In C. canerivorus the number is pm. §, m. und M. Filhol [op. cit .) has shown that in the long-jawed domestic 
races like the greyhound m.3 is occasionally present, while in the short.jawed races like the bull-dog is sometimes absent. 
3 Huxley, op. cit., fig. .13. 
