15G 
DISTRIBUTION OF EXTINCT ANIMALS. [part ii. 
they flourished in Europe during the Miocene age — animals as 
large (in some species) as a rhinoceros, and most allied to living 
African forms. In North America no trace of Edentata has been 
found earlier than the Post-Pliocene period, or perhaps the Newer 
Pliocene on the west coast. Neither is there any trace of them 
in South America in the Eocene formations ; but this may well 
be owing to our very imperfect knowledge of the forms of 
that epoch. Their absence from North America is, however, 
probably real ; and we have to account for their presence in the 
Old World and in South America. Their antiquity is no doubt 
very great, and the point of divergence of the Old World and 
South American groups, may take us back to early Eocene, or 
even to Pre-Eocene times. The distribution of land and sea may 
then have been very different from what it is now’ ; and to those 
who would create a continent to account for the migrations of 
a beetle, nothing would seem more probable than that a South 
Atlantic continent, then united parts of w 7 hat are now Africa 
and South America. There is, however, so much evidence for 
the general permanence of what are now the great continents 
and deep oceans, that Professor Huxley’s supposition of a con- 
siderable extension of land round the borders of the North Pacific 
Ocean in Mesozoic times, best indicates the probable area in 
which the Edentate type originated, and thence spread over much 
of the Old World and South America. But wdiile in the latter 
country it flourished and increased with little check, in the 
other great continents it jvas soon overcome by the competition 
of higher forms, only leaving a few small-sized representatives 
in Africa and Asia. 
