The eggs of this bird, which is said to be smaller and duller colored than the northern variety, show no differences in any respect.

762. SAN LUCAS ROBIN. _Planesticus confinis._

Range.--Southern Lower California.

This is a very much paler form of the American Robin; its eggs probably will not differ from those of the others.

[Ill.u.s.tration 449: J. B. Pardoe. NEST AND EGGS OF ROBIN.]

[Ill.u.s.tration: right hand margin.]

Page 448

763. VARIED THRUSH. _Ixoreus naevius naevius._

Range.--Pacific coast from northern California to Alaska; south to Mexico in winter.

These handsome birds breed abundantly in Alaska and locally in mountain ranges south to northern California. They nest at low elevations in trees, making them of moss, twigs, weeds and gra.s.ses, forming a flat shallow structure. Their eggs are greenish blue sharply but sparingly spotted with dark brown; size 1.12 .80. Data.--Delta of Kowak River, Alaska, June 11, 1899. Four eggs. Nest 12 feet from the ground, against the trunk of a slender spruce and supported by a clump of stiff twigs.

763a. NORTHERN VARIED THRUSH. _Ixoreus naevius meruloides._

Range.--Interior of western North America, breeding from British Columbia to Alaska. Its habits and eggs do not differ from those of the last.

764. SIBERIAN RED-SPOTTED BLUETHROAT. _Cyanosylvia suecica robusta._

Range.--Northern Asia; casually to Alaska.

This beautiful foreigner nests on the ground and lays four to six greenish blue eggs, spotted with reddish brown; size .75 .50.

765. WHEATEAR. _Saxicola nanthe nanthe._

Range.--Asia; casual in Alaska in summer; nesting habits and eggs like the next.

765a. GREENLAND WHEATEAR. _Saxicola nanthe leucorhoa._

Range.--Europe and Greenland; casual on the Atlantic coast of North America.

This very abundant Old World species is a common breeding bird in Greenland and probably also in Labrador. They nest in crevices of quarries, holes in the ground, or stone walls, making a rude nest of weeds, moss or gra.s.ses, lined with hair or feathers, and during May lay from four to six pale greenish blue eggs; size .90 .60.

[Ill.u.s.tration 450: Greenish blue.]

[Ill.u.s.tration: Wheatear.]

[Ill.u.s.tration: Pale greenish blue.]

[Ill.u.s.tration: left hand margin.]

Page 449

[Ill.u.s.tration 451: BLUEBIRD.]

Page 450

766. BLUEBIRD. _Sialia sialis sialis._

Range.--Eastern United States, breeding from the Gulf to southern Canada. Winters in the southern half of the United States.

These familiar birds build in cavities in trees, usually below 20 feet from the ground, crevices among ledges, bird boxes and in any suitable nook they may discover about buildings, providing that English Sparrows do not molest them. They raise several broods a year, commencing in April when they lay from three to six pale bluish white eggs (rarely pure white); size .80 .60. The cavities of their nesting sites are lined with gra.s.ses and feathers usually, although I have found the eggs on the unlined bottom of cavities in trees.

766a. AZURE BLUEBIRD. _Sialia sialis fulva._

Range.--This pale variety is found in southern Arizona and southward.

Its nesting habits are the same and the eggs are indistinguishable from the last.

767. WESTERN BLUEBIRD. _Sialia mexicana occidentalis._

Range.--Pacific coast from Lower California to British Columbia.

The Western Bluebird is as common and familiar in its range as the common Bluebird is in the east. It nests in similar locations and its eggs are scarcely distinguishable, although averaging a trifle darker in shade; size .80 .60.

767a. CHESTNUT-BACKED BLUEBIRD. _Sialia mexicana bairdi._

Range.--Rocky Mountain region from Mexico to Wyoming.

The nesting habits or eggs of this brighter colored bird do not differ from those of the last species.

767b. SAN PEDRO BLUEBIRD. _Sialia mexicana anabelae._

Range.--San Pedro Martir Mountains in Lower California.

The eggs of this variety will not in all probability be any different from those of the preceding Bluebirds.

768. MOUNTAIN BLUEBIRD. _Sialia currucoides._

Range.--Rocky Mountain region, breeding from New Mexico north to Great Slave Lake; winters in southwestern United States and Mexico.

This azure blue species is common in the greater part of its range and is found west to the Sierra Nevadas in California. Like the eastern Bluebird they nest in holes in trees or anywhere that they can find a suitable cavity or crevice. Their eggs are slightly larger than those of the other Bluebirds and have a slight greenish tint; size .85 .64.

[Ill.u.s.tration 452: Bluish white.]

[Ill.u.s.tration: Bluebird.]

[Ill.u.s.tration: left hand margin.]