KEEL-BREASTED BIRDS. 263 
typical form, found east of the central plains of North 
America, They migrate in communities of millions, cov- 
ering every limb and branch of forests twenty or thirty 
miles in extent, breaking down great trees and limbs, 
rising in the air like clouds, darkening the sun, and creat- 
ing a sound with their wings like the roaring of a hurri- 
cane, or of distant thunder; and so rapid is their flight 
that they attain a speed of more than a mile a minute. 
The nests are of twigs rudely placed together, often one 
hundred in a single tree, in which two eggs are laid, pro- 
ducing generally a male and female. They are fed with 
a milky fluid from the stomach of the parents. 
Of all the 
pigeons of the 
Old World, the 
crowned pigeon 
(Goura victore) 
of New Guinea 
and the toothed 
pigeon (Didun- 
culus  strigtros- 
tris), of the Nav- 
igator Islands, 
are most re- 
markable. 
The famous é 
dodo ( Didus in- FIG. 297.—Dodo, an extinct giant pigeon. 
eptus) (Fig. 297) 
lived upon the Island of Mauritius in 1598, but so com- 
plete is its extinction by man that it is now only known by 
a few pictures, bones, feathers, and other parts, in a few 
museums, It was a pigeon-like bird as large as a swan, 
with an enormous hooked bill and rudimentary feathers. 
The solitaire (D. solitarius) and Nazarene (D. nazare- 
nus) are other allies that have disappeared within com- 
paratively a few years. 
