EVOLUTION OR LIFE. 
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2 
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extinct Marsupials allied to the Thylacinus. This view 
has much in its favor, as the transition from the pouch- 
bearers to the ordinary mammals is very gradual, as, for 
example, the smaller Opossums lead up to the Insectivora 
(Hedgehog), the Wombat to the Beaver, etc. The fact of 
Australia, with few exceptions, containing only the reptile- 
bird-like and pouch-bearing mammals at the present day 
seems to confirm the view of the ordinary mammals com- 
ing from the pouch-bearers in some such way; for while 
we find in other parts of the world fossil remains of 
Marsupials, with the exception of the Opossums, the living 
pouch-bearers are found only in Australia and the adjacent 
islands, the fossil remains being Marsupials, but of a much 
larger size. Australia seems to offer us a living picture 
of what Europe once has been. Just as in Europe and 
other places, among the ordinary mammals, we have vari- 
ous kinds preying on each other, so we find the same thing 
among the existing pouch-bearers in Australia; and this 
relation existed also in past time. The Diprotodon (a 
gigantic Kangaroo) was warred upon by the Thylacoleo, a 
meat-eater of the size of a lion. Supposing this view of 
the origin of the ordinary Mammalia to be correct, the 
number of branches descending from the pouch-bearers 
will depend on the view taken by naturalists of the affini- 
ties of the different orders. Although there are twelve 
orders in the ordinary Mammalia, some of them seem 
directly or indirectly to be more nearly related than others. 
Thus, the order of odd-toed (Rhinoceros, Tapir, Horse) and 
that of even-toed (Pig, Hippopotamus, Sheep, Deer) are 
16y. 
مہم 
joined in one group, the Ungulata, or hoofed animals: t 
would represent one stem. The Half-Apes, the gnawing ani- 
mals, with the Hyrax and Elephant, the insect-eaters, the 
— 
1 man, would make a second stem. 
bats, and true Apes, wit 
The meat-eaters (Lion, Fig. 81, Dog, Seal, etc.) may repre- 
sent a third stem; while the Edentata, or animals without 
twenty-tWi 
and the pe 
animals art 
forming à 
Paleotherit 
even-toed ) 
the Cow, SI 
skull and te 
(nineteen). 1 
tem form t] 
exist three 
food until j 
and Llama 
