758c. Alma's thrush. Hylocichla ustulata alamæ. Rare summer resident; in migration common.
759. Dwarf hermit thrush. Hylocichla aonalaschkæ. Rare migrant.
759a. Audubon's hermit thrush. Hylocichla aonalaschkæ auduboni. Common summer resident; breeds from 8,000 feet to timber-line.
759b. Hermit thrush. Hylocichla aonalaschkæ pallasii. Rare migrant; comes to the eastern edge of Colorado, just touching range of auduboni.
761. American robin. Merula migratoria. Summer resident, but not common; some interesting questions arise in connection with intermediate forms.
761a. Western robin. Merula migratoria propinqua. Abundant summer resident; breeds from plains to timber-line.
765a. Greenland wheatear. Saxicola œnanthe leucorhoa. European species; a straggler taken at Boulder by Minot.
766. Bluebird. Sialia sialis. Rare summer resident; west to base of Rockies.
767a. Chestnut-backed bluebird. Sialia mexicana bairdi. Summer resident; not common; western form, coming east as far as Pueblo.
768. Mountain bluebird. Sialia arctica. Abundant summer resident; breeds from plains to timber-line; in autumn roams up to at least 13,000 feet.