The Olive-sided Flycatcher 
Mountains seemed to say; and if they warned us once, they did a thousand 
times. “Well, what of it?” we were minded to retort. But miners, 
toiling in the depths of the Sierras, come to regard the brisk evening 
greeting of this flycatcher as one of the compensations of solitude. “Hip! 
Three cheers!” says the bird as he sees his friends emerging from the 
tunnel’s mouth; and the miners shout, “Hooray!” 
Borealis is a bird of the treetops, and nearer you cannot come, 
save in nesting time, when caution is thrown to the winds, and studies 
in morbid psychology are all too easy. The birds place a rustic saucer 
of interwoven twigs and mosses, lined with rootlets, upon the upper side 
of a horizontal branch, whether of yellow pine, tamarack pine, or fir 
tree; and as often as otherwise at moderate heights. The small bird 
usually maintains a prudent aloofness in the early days; but as incubation 
advances, his solicitude breaks bounds. Then both birds betray uneasi¬ 
ness at the approach of strangers and begin to flit about, with restless, 
tittering cries, tew-tew, tew-tew, or tew-tew-tew, sounds which strangely 
excite the blood of the oologist. Once the nesting tree is made out 
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