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BIRDS 
SUMMARY 
Because of their feathers birds can easily be recognized. 
The fore-limbs are adapted for flying, and as such vary in 
size. The feet are modified for swimming, running, perch¬ 
ing, or tearing; while the jaws are large and powerful, or 
small and weak, depending on the habits of the bird. The 
classification of birds according to their habits makes it 
easy to learn about them. Birds are of great economic 
importance in destroying many kinds of insects that are 
detrimental to man. This explains why they must be pro¬ 
tected by law. 
TABLE —SIZE OF NESTING BOXES 
Bird 
Diameter of 
Opening 
Size of 
Cavity 
Location 
Chickadee. 
11 n 
1 8 
4X4 
In protected spots 
House wren. 
11 " 
X 8 
4X4 
Trees and arbors 
Nuthatch. 
11 " 
1 4 
5X6 
On buildings or trees 
Bluebird. 
11 " 
1 4 
5X6 
On buildings or trees 
Tree-swallows .... 
11 // 
J-4 
5X6 
In trees near ponds 
Red-headed woodpecker 
2i" 
6X7 
On posts or trees 
Flicker. 
3" 
6X8 
On posts or trees 
Wood-duck. 
6" 
10 X 18 
Trees or stumps 
QUESTIONS 
How many birds do you know? What do they eat? Do they 
remain all winter ? Which ones migrate ? Where do they nest ? What 
time of year do the young leave the nest? Why are the birds bene¬ 
ficial ? 
REFERENCES 
W. L. McAter, How to Attract Birds in Northeastern United States. 
Farmers’ Bulletin 621. 
Chapman, Bird Life. 
