Arrangement of the Fossil Kangaroos. 205 
Thylacoleo was the last representative of this early progenitor 
of our marsupials; and in this form only occur carnivorous 
grinders with an otherwise herbivorous dentition. There 
must have been numerous intermediate forms totally lost, or 
not yet discovered, which would clear up our doubts upon the 
subject ; so much is certain, however, that with the T’hylacoleo 
disappeared the nearest relation of the most ancient form of 
marsupial life in this country. 
Supposing, then, this hypothesis to be correct, we can well 
account for the development of the rest of the pouched tribe, 
and simply divide them into two groups,—No. 1 embracing 
all the members with a pair of small conjointed inner toes— 
that is, kangaroos, rat-kangaroos, wombats, phalangers (opos- 
sums, flying squirrels, native bears, &c.), and bandicoots ; 
whilst No. 2, on the other hand, comprises the true flesh-eaters, 
without the conjoined inner pair of toes, such as the Tasmanian 
tiger and devil, the dasyures or native cats, and the small fry 
of pouched mice. 
All our marsupials can be received into one or the other of 
these groups; so that, after all, the classification of them is 
easy enough. It may be argued that the dentition varies 
much ; but when we study embryonic life and the development 
of the teeth, we soon find the missing links; and if a person 
will only take the trouble to look for himself before implicitly 
believing what is published, he will soon change his opinion. 
Let us take a wombat, an opossum, and a bandicoot for a com- 
parison : and certainly there are not three animals in the group 
more different from each other than these ; but all three possess 
the conjoined toes to the hind feet. When the teeth of a very 
young wombat are examined, it becomes also clear that they 
are furnished with crowns or working-surfaces which very 
much resemble those of our common phalanger or opossum ; 
and when we take the trouble to disengage the grinders of 
certain bandicoots, such as the Peragalea or rabbit-rat, we 
behold a “small edition” of a true wombat’s grinders. Of 
course it is necessary to find out such things by actual ex- 
amination ; and it must be admitted that few persons have the 
opportunity, or, if so, make use of it. 
The native bear is the diminutive representative of the 
gigantic extinct Phalangers, the Diprotodons, and Nototheres ; 
and he is also the most ancient living form of marsupial life, 
probably connected by innumerable unknown species with the 
lower section to which the platypus belongs. At any rate, 
there is no other animal known to me which, at an early 
period of its existence, has grinders resembling the horny 
‘apologies for teeth’ wherewith our “ duckbill” is supplied 
