chap, xi.] THE ETHIOPIAN REGION. 287 
and helped to form a great southern continent which must at one 
time have extended eastward as far as Southern India and 
Ceylon ; and over the whole of this the lemurine type no doubt 
prevailed. 
During some portion of this period, South Temperate Africa 
must have had a much greater extension, perhaps indicated by 
the numerous shoals and rocks to the south and east of the 
Cape of Good Hope, and by the Crozets and Kerguelen Islands 
further to the south-east. This would have afforded means for 
that intercommunion with Western Australia which is so clearly 
marked in the flora, and to some extent also in the insects of the 
two countries ; and some such extension is absolutely required 
for the development of that wonderfully rich and peculiar 
temperate flora and fauna, which, now crowded into a narrow 
territory, is one of the greatest marvels of the organic world. 
During this early period, when the great southern continents 
— South America, Africa, and Australia — were equally free from 
the incursions of the destructive felines of the north, the 
Struthious or ostrich type of birds was probably developed into 
its existing forms. It is not at all necessary to suppose that 
these three continents were at any time united, in order to 
account for the distribution of these great terrestrial birds ; as 
this may have arisen by at least two other easily conceiv- 
able modes. The ancestral Struthious type may, like the 
Marsupial, have once spread over the larger portion of the globe ; 
but as higher forms, especially of Carnivora, became developed, 
it would be exterminated everywhere but in those regions 
where it was free from their attacks. In each of these it would 
deveiope into special forms adapted to surrounding conditions; and 
the large size, great strength, and excessive speed of the ostrich, 
may have been a comparatively late development caused by its 
exposure to the attacks of enemies which rendered such modi- 
fication necessary. This seems the most probable explanation 
of the distribution of Struthious birds, and it is rendered almost 
certain by the discovery of remains of this order in Europe in 
Eocene deposits, and by the occurrence of an ostrich among the 
fossils of the Shvalik hills; but it is just possible, also, that the 
