570 
BIRDS OF NEW MEXICO 
ALASKA HERMIT THRUSH: Hylocichla guttata guttAta (Pallas) 
Description. —Adult male: Length (skins) 5.5-G.5 inches, wing 3.4-3.5, tail 
2.4-2.7; bill .4-.5, tarsus 1.1-1.2. Female slightly smaller. Adults: Upperparts 
dark grayish-brown, more olive-brown in winter, tail cinnamon-brown , more reddish- 
brown in winter; eye-ring white, conspicuous; underparts white, lower throat with 
I-'rora Biological Survey 
Fig. 99. Russet-backed Thrush 
narrow wedge-shaped streaks, chest thickly marked with large spots; sides brownish 
gray; bill dusky, flesh-colored at base. Young: Upper parts streaked with buffy; 
breast, upper belly, and sides barred with black or dusky. 
Comparisons. —The Alaska Hermit Thrush can be distinguished from the Audu¬ 
bon by its smaller size and darker coloration. But the identification of the various 
hermit thrushes is a matter of comparative measurements and shades of color, so 
that, before collectors make definite records of specimens, they should send them to 
a museum or to the Biological Survey for comparison with series of skins. 
Range. —Breeds mainly in Hudsonian Zone from Mount McKinley, Alaska, 
south to Kadiak Island, Cross Sound, and northern British Columbia (east of coast 
ranges); winters in southern Arizona and south to Tamaulipas, Nuevo Leon, Chihua- 
