AN ORNITHOLOGICAL LECTURE. 103 
the far north-west. In the materials used, and the con- 
struction of the nest, birds adapt themselves largely to cir- 
cumstances. In the Northern States, for example, the Bal- 
timore oriole uses hempen fibres, cotton twine, e¢ cetera, for 
its nest; but in the heat of Louisiana the same pouch-shaped 
THE WOOD-PEWEER, 
structure is woven of Spanish moss, and is light and cool. 
The intelligence and foresight that some birds exhibit in 
their architecture prove reason rather than instinct, as we 
popularly use these words; while others are so stupid as to 
upset all our respect for their faculties of calculation. Both 
sexes usually help in building the nest, and work industri- 
