This bird differs from the above in the red of the bill being more blackish at the tip, and the under parts being a pearly gray in place of white, tail not quite as much forked, and shorter; edge of outer primaries and outer tail-feathers blackish.
Nest.—These breed much more abundantly on the Atlantic coast. Their eggs are more rounded (1.75 × 1.40).
ARCTIC TERN.
71. Sterna paradisæ. 15 inches.
A similar bird to the last; more northern in its distribution; and the pearly gray mantle somewhat darker both above and below. Bill quite red and feet much smaller and bright red. When their nesting colonies are approached they will rise in clouds, circling about high in the air, uttering at times their peculiar cry.
Nest.—Similar to the others, with very little if any attempt at nest building. Usually placing the two or three eggs on the bare sand or gravel just above the water line. There is no difference in the color or markings of the eggs from the others (1.75 × 1.40).
Range.—More northerly than the preceding, to the Arctic Regions and wintering from California to the Gulf States.
ALEUTIAN TERN.
73. Sterna aleutica. 15 inches.