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 KEY, OR TABLE, FOR CLASSIFYING BIRDS (Class Aves) INTO ORDERS                                                                 A_{1} Wings not suited for flight, 2 or 3 toes                A_{2} Wings suited for flight (except the penguin)    B_{1} Toes united by a web for swimming, legs short

C_{1} Feet placed far back; wings short, tip not reaching to base of tail (Fig. 300)

C_{2} Bill flattened, horny plates under margin of upper bill (Fig. 323)

C_{3} Wings long and pointed, bill slender

C_{4} All four toes webbed, bare sac under throat

B_{2} Toes not united by web for swimming

C_{1} Three front toes, neck and legs long, tibia (shin, or "drumstick") partly bare

C_{2} Three front toes, neck and legs not long

D_{1} Claws short and blunt (e, Fig. 300)

E_{1} Feet and beak stout, young feathered, base of hind toe elevated

E_{2} Feet and beak weak, young naked

D_{2} Claws long, curved and sharp, bill hooked and sharp

D_{3} Claws long, slightly curved, bill nearly straight

C_{3} Two front and two hind toes (Fig. 300)

D_{1} Bill straight, feet used for climbing

D^1 Bill hooked, both bill and feet used for climbing

The Food of Birds.—Extracts from Bulletin No. 54 (United States Dept. of Agriculture), by F. E. L. Beal.

The practical value of birds in controlling insect pests should be more generally recognized. It may be an easy matter to exterminate the birds in an orchard or grain field, but it is an extremely difficult one to control the insect pests. It is certain, too, that the value of our native sparrows as weed destroyers is not appreciated. Weed seed forms an important item of the winter food of many of these birds, and it is impossible to estimate the immense numbers of noxious weeds which are thus annually