188 REPTILES AND BIRDS. 
a fact truly inexplicable, in spite of every hypothesis more or less 
reasonable which has been advanced by naturalists. 
Men have no control over birds, and therefore opportunities of 
studying their habits in a state of nature are few. Some species 
may be retained in captivity, and observers have been able to gain 
a knowledge of them while in that condition ; but, except two of 
three species, it has been impossible to reduce them to a state ot 
domestication. ‘The habits and manners of the feathered race are, 
therefore, entirely dependent on chance observation. 
The Humming-bird we know is confined to certain portions of 
America. The Nightingale, if a visitor to Scotland, is only found 
in Berwick and Dumfriesshire in fine seasons, while it is constantly 
seen in Sweden, a country much colder and much more northerly. 
The Toucans, so brilliant in plumage, are only found in tropical 
South America. The Swallow, so rapid on the wing, clearing its 
twenty leagues an hour when it leaves us for its southern winter 
quarters, never deviates from the route which seems to have been 
traced for it by a sovereign master, but the reasons we cannot 
define. 
It may, then, be stated that the great zones of the earth differ 
as much in Birds as in the Mammifers found in them. We find in 
climatic regions birds, or groups of birds, of perfectly distinct species, 
and which are rarely found beyond that particular zone. Glancing 
at the various countries forming a region, particular types of birds 
are easily recognised. Africa, for instance, alone possesses the Great 
Ostrich, while only a small species exists in America, the Rhea ; 
the Emu represents the genus in Australia, and the Cassowary in 
the Malaccas. Africa has species of birds brilliant as the most 
precious stones. To America belong exclusively the Humming- 
birds, so remarkable for the brilliancy of their plumage. Again, 
if Africa is the country of the Vulture, to America belongs the 
Condor. 
Nevertheless, the acclimatisation of birds is by no means beyond 
our power. Experience proves that by carrying a bird far from its 
native country, and placing it in conditions approaching those to 
which it has been accustomed, it will live and multiply—acclimate 
itself, in short, to its new home. 
Europe possesses no ornithological type peculiar to it. It is 
only in Africa and America that we find those rich varieties of form 
and colour which characterise the feathered race. The Island of 
Madagascar is the land which possesses the greatest number of orni- 
thological types—simply, perhaps, because that island abounds in 
