feathers for nearly ¡111 inch above the knee joint, are as the toes,
black; claws, strong and curved, black; webs, black.
The female is not quite so large as the male.
The young arc at first covered with white down. Before their first
autumnal moidt they have the bill dull red, the tip black; forehead
and crown, white; chin, throat, and breast, white; back', greyish
brown, with some bars and patches of a darker brown or blackish;
greater and lesser wing coverts, also greyish brown, with marks of a
darker colour; primaries, dark blackish brown. Greater and lesser
under wing coverts, white. The tail is dark blackish brown at the end.
Besides the autumnal moult, the Terns change part of their plumage
in the spring.
