KEEL-BREASTED BIRDS. 291 
moss ever kept green from the spray of the falls. The 
entrance is a doorway formed in the moss, leading to the 
interior, which is 
lined with soft 
grasses, and con- 
tains four or five 
pure white eggs. 
The large fam- 
ily of thrushes 
(Zurdid@) is rep- 
resented by the 
robin, mocking- 
bird, cat-bird, 
and others. The 
wood thrush is 
the highest of the 
ciass of birds. 
The pervading 
color is  cinna- 
mon-brown, grad- 
ing into olive on 
the rump, the 
breast blocked or 
marked with dis- 
tinct spots. They attain a length of eight inches, and are 
noted for their glorious powers of song, resembling the 
tinkling of a bell or the soft notes of a flute. The nest is 
found in low hollows, and contains four or five blue eggs. 
Specimens for Study.—For purposes of study, the skele- 
ton of a common fowl or other bird offers good material. 
The flesh can be boiled away, and the bones arranged as 
in Fig. 268; the limbs and skull should be compared with 
the corresponding parts of reptiles and mammals, and the 
difference noted. If the skeleton is to be mounted, the 
bird should be skinned and macerated. The tools neces- 
sary for work are a hook for suspending large specimens, 
Fic. 320.—Bird architecture: Hanging tit and 
nest. 
