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First of all, feathers are different in kind and have different uses. 

 The most characteristic, or special use is for flight. For the water birds 

 the feathers are arranged as a boat in which they can float. The bird 

 would sink without its feathers. For all birds, feathers keep warm in 

 in cool weather, protect from the rays of the sun in hot weather, pro- 

 tect from rain, from scratches and other mechanical injury in flying, or 

 in running through brush, etc. They serve as ornamentation to dis- 

 tingnish each other and to attract mates. 



Examination of feathers. To have a basis for comparison examine 

 the parts of a single feather, e. g. a wing feather. It consists of an axis 

 running its length called the sft'/n. The hollow part of this is the quill. 

 The whole of the broad portion is the vatte. The axis of the vane is 

 the rachis. The branches of the rachis are the barbs, and the minute 

 branches of the barbs are the barbules. 



The wing feathers and often the tail feathers are large and strong. 

 The barbs and barbules of each feather adhere quite firmly, and the 

 feathers overlap so that when the wing is extended it presents a broad 

 firm surface with which to strike the air. Have the pupils separate the 

 barbs and barbules, smooth them till they again adhere and examine 

 them with a microscope or hand lens to determine how they adhere. 



The contour feathers are those all over the body whose ends come out 

 on the surface and overlap one another like shingles on a house. The 

 barbules on the outer ends adhere as in the wing feathers. These thus 

 fitting over each other make the outline of the body, and when well 

 oiled as in many birds, they make a good waterproof coat. The inner 

 ends have barbs and barbules, very fine and not united, being downy. 



The down feathers have all their barbs very fine and diffuse. These 

 feathers have minute quills, and being next the body are for warmth. 

 They make a soft backing for the contour feathers and thus also give 

 protection against injury, and help make the "float" for the swimming 

 bird's body to rest in. 



Many birds have oil glands at the root of the tail from which they get 

 oil to rub on the feathers. 



Ornamental feathers of many forms are interesting — such as in the 

 tails of roosters, peacocks, etc. 



The color markings on the feathers of birds may form a series of good 

 lessons. How they are arranged; how they sometimes extend from 

 feather to feather to make definite figures, etc.; how in some the mark- 

 ings are stripes so arranged that the birds can hardly be seen in the dry 

 grass; in others, brilliant to attract the attention of mates, etc. Always, 

 if possible, procure the bird for the lesson. 



The moulting, or shedding of feathers is an interesting subject. Why 

 do they moult? How often? In what manner? are some of the ques- 

 tions to be put. Most birds moult annually. Some, twice a year (Ptar- 

 migans in fall get a white plumage so they may not be easily seen on the 



