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 How long is taken to lay a sitting of eggs? How long before the birds are hatched? When hatched are they helpless? Blind? Feathered? (Figs. 301, 302.) Do the nestlings require much food? How many times is food brought in an hour? How distributed? Even if the old birds sometimes eat fruit do they take fruit to the young? What do they feed to the young? How long before they leave the nest? Do the parents try to teach them to fly? Do the parents care for them after the nest is left? What songs or calls has the bird?

What are the advantages of its shape?

(India).

Instinct for nest building highly perfected.

General Field Study.—(For written report.) Name the best and poorest flyers you know; birds that fly most of the time; birds that seldom fly. Observe birds that pair; live in flocks. Does their sociability vary with the season? Do you ever see birds quarreling?