360 
INSECTIVOROUS BIRDS. 
( Asperula odorata), neatly arched over, perhaps, by a 
withered fern leaf, surmounted by a coating of green 
moss, and a few additional pieces of other slender ma- 
terials. The lining is similar, but finer and smoothly 
arranged. Sometimes, under a bridge, the same pair 
have been known to renew their labors in the same place 
for three successive times. The young, from their situa- 
tion, are readily supplied with fish, their appropriate food. 
The eggs are 4 to 6, and white. Such are the habits 
of the common Dipper, which, in great part, also prob- 
ably apply to the American bird. 
The length of Pallas’s Dipper or Ousel is about 8^ inches. The 
whole bird is of a dark grayish slate color ; at the upper orbit of the 
eye there is a slight indication of whitish. The general color some- 
what deeper on the head, and a shade lighter beneath. The prima-* 
fries incline somewhat to brown. Tail even. Feet flesh-color, 
THE WARBLERS. (Sylvia, Lath.) 
In these the bill is slender, straight, awl-shaped, higher than 
it is wide at the base, and furnished with scattered bristles ; the lower 
mandible straight. Nostrils basal, lateral, oval, half closed by a 
membrane. Tongue lacerated at tip. Tarsus longer than the mid- 
dle toe ; inner toe free ; posterior nail shorter than the toe. — 
Wings moderate or short ; spurious feather generally short ; 1st and 
2d primaries, 2d and 3d, or 3d and 4th longest; scapulars considera- 
bly shorter than the quill feathers. 
The female generally distinguished by a less vivid plumage. The 
young usually resume the adult livery after the first moult. They 
moult once, though in some species twice in the year. 
Of this numerous genus there are species spread over the whole 
globe. They are generally small, sprightly, and endowed with an 
incessant activity, in accordance with the subtleness of their flying 
insect prey ; they therefore approach both in habit and character the 
Flycatchers, Vireos, Thrushes, Saxicolas, and Wrens so nearly, that 
