30 
ROUTES OF MIGKATIOK. 
birds is one of the welcome signs of the maturing year. Tlie swallow, 
more particularly, is the herald of sunshine and bright days. So one 
of our Scottish poets hastens to greet him with a song : — 
" The little comer's coming, 
The comer o'er the sea., 
The comer of the summer, all 
The sunny days to be. 
How pleasant through the pleasant sleep 
Thy early twitter heard, 
O swallow by ' the lattice I " 
Glad days be thy reward I " 
More than half the birds of Europe, of Northern Asia, and North 
America, are migratory birds. Most steer their course towards the 
KLIGHT OF WILD SWANS. 
genial bowers of the South ; those of the eastern hemisphere towards 
the south-west, and those of the western towards the south-east, 
according to the configuration of the countries where they winter. 
Their routes are the rivers and valleys which extend in the direction 
of their migrations; and the deep valley-basins, enclosed by mountains, 
are their places of reunion. Some travel in pairs ; othei-s in more or 
less numerous bands. The weaker species pui-sue their way under the 
protecting cover of night; the majority migi-ate during the daytime. 
They set out before famine comes upon them, advancing with great 
