280 PERCHERS AND SINGERS 
This bird is a diving thrush! Nature has fitted it to dive 
boldly into the coldest and most turbulent water, or through 
a water-fall, and even to walk on the bottom of a still pool in 
search of food, without being at all disturbed. Both in form 
and size this little creature is like a large wren, but it is so 
peculiar it occupies a genus quite alone. Of course it is not 
web-footed; and in appearance it exhibits not one feature sug- 
gestive of a semi-aquatic life. Its home is along the foaming 
torrents of the Rocky Mountains, and Sierra Nevadas, from 
Alaska to Guatemala. It nests close beside swift-running 
streams, sometimes beside or even behind a cascade. It is 
known that this strange bird gives forth a song both clear and 
sweet, but I have never seen one elsewhere than near a roar- 
ing torrent, where no ordinary bird song could be heard. 
THE WARBLER FAMILY 
Mniotiltidae 
From the middle of April to the middle of September the 
woods and thickets of the northern states are inhabited by a 
very considerable number of tiny bird forms. They are trim- 
built little creatures, quiet and businesslike, and they take 
themselves very seriously. A few of them are clad in refined 
shades of yellow, but—most fortunately—the great majority 
wear dull olive, gray or brown colors, and thereby escape 
the hostile attention that bright plumage always attracts. 
These are the warblers, very useful in the destruction of 
insects, but the most elusive and difficult little creatures with 
which bird students have to deal. 
The high-water mark in insect destruction by our birds is 
