BIRDS OF THE UNITED STATES. 
67 
follows : External diameter, three inches ; internal, two and a quarter 
inches; depth inside, three-fourths, and outside, one and an eighth inches. 
The nest being finished, oviposition commences on the ensuing day, 
and proceeds at the rate of one egg daily, until the entire number is laid. 
This varies from three to five, even in the same locality. Incubation 
commences on the day after the last deposit has been made, and continues 
for a period of ten days. It is chiefly the duty of the female, although 
the male occasionally lends his assistance by taking the nest. When not 
thus occupied, he either polices the premises to guard against intrusion, or 
is away in search of food. When with young both birds become devoted 
parents, and evince the greatest anxiety and consternation when their nest 
is disturbed. 
Their actions at such times bespeak fear rather than courage. We 
have never known them to assume the threatening attitude which charac- 
terizes so many of our small sj^ecies, nor seek to drive intruders away by 
sharp scoldings and angry gesticulations. But knowing that resistance 
would be useless, they quietly submit to circumstances, and repair to other 
scenes where they think to he secure from molestation and harm in carry- 
ing out the chief object of their being. 
The young are fed at first on various larvae, esj>ecially those of a lepi- 
dopterous character. To these, earth-worms, aphides, beetles and flies are 
added as condition and age require. When twelve days old they are per- 
suaded to leave the nest, and, under the direction of the paternal sire, 
receive instruction in bird-lore. A period of eight or nine days more, and 
they earn their own living. They do not forsake their parents, however, 
but follow them into their old hunting-grounds, and thus help to consti- 
tute the small flocks which are generally observed in the fall of the year 
in our Eastern and Middle States, previous to migration. 
The eggs are ohlong-oval in shape, and vary considerably in size. 
They are of a bluish-green color, and are sparingly spotted with umber 
and dark brown markings about the larger extremity. In some specimens. 
