ROCK WREN. 
715. NSalpinctes obsoletus. 5% inches. 
Upper parts stone color, specked with black; rump 
brownish; underparts whitish with indistinct streaks 
on the throat. 
A common bird on the dry, rocky foothills of the 
Rockies and westward. They are well named, for their 
favorite places are among the rocks, where they are 
always busily engaged in hunting insects or spiders in 
the crevices. Owing to their colors and their habits of 
slinking away behind the rocks they are quite difficult 
to see, but their sweet song is always heard if any of 
the birds are in the vicinity. 
Song.—Very sweet and varied, almost canary-like, 
but impossible to describe; call, a harsh grating note. 
Nest.—Of sticks, weeds, grasses, ete., concealed in 
crevices among the rocks; the five or six eggs are white, 
sparingly specked with reddish brown (.72 x .54). 
Range.—Western U. 8. from the western border of 
the Plains to the Pacific, north to Dakota and British 
Columbia; winters from southwestern U. 8. southward. 
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