A.
319. How many individual parts does a featherhave?
The parts of a single featheradd up to more than a million individual units, many of them so small they canonly be seen with the help of a microscope. These parts interlock to form an extremely strong, light plane of greatflexibility.
The parts of a single featheradd up to more than a million individual units, many of them so small they canonly be seen with the help of a microscope. These parts interlock to form an extremely strong, light plane of greatflexibility.
B.
321. Are the feathers of a bird alive?
As long as the feather is growing, its softcentral is fed with blood vessels which supply pigments and food. Once the feather is fully mature, that is,has lost all of its sheath and is fully expanded, it hardens, the food supplyis cut off, and the whole structure is made up of dead epidermis. The feather may then be considered dead,though it continues to be firmly clasped by the feather follilcle until thenext
E.
As long as the feather is growing, its softcentral is fed with blood vessels which supply pigments and food. Once the feather is fully mature, that is,has lost all of its sheath and is fully expanded, it hardens, the food supplyis cut off, and the whole structure is made up of dead epidermis. The feather may then be considered dead,though it continues to be firmly clasped by the feather follilcle until thenext
molt.
D.
E.
326. What are down feathers?
Theseare soft feathers without a shaft and having barbs that are but soft fluffytufts. They are extremely strong andresilient. They provide the covering ofmany newly-hatched birds , particularly those of the precocial group. Some species of birds as adults have a downundercoating beneath their contour feathers. Ducks and geese have such an undercoating.
Theseare soft feathers without a shaft and having barbs that are but soft fluffytufts. They are extremely strong andresilient. They provide the covering ofmany newly-hatched birds , particularly those of the precocial group. Some species of birds as adults have a downundercoating beneath their contour feathers. Ducks and geese have such an undercoating.
F.
G.
327. What are powder-down feathers?
H.
I.
Thesescarcely seem like feathers at all. Theyform a powdery substance on some areas of the skin of such birds as herons andbitterns. These birds rub their bills inthe powder-down feathers and spread the resulting powder over their plumage,giving it a “bloom” which rubs off when the bird is handled.
H.
I.
Key to Illustrations:
A. Indian peacock photographed by Jebulon.
B. Feather structure diagram.
C. Parts of the feather: (1) Vane; (2) Rachis; (3) Barb; (4) After-Feather; (5) Hollow shaft (calamus)
D. Feather structure of a blue-and-yellow Macaw.
E. Common female eider duck with down photographed by Frederic Levier.
F. Plumes. Illustré par AdolpheMillot dans Larousse pour tous [1907-1910]. Aigle, Hibou, Goura,Argus, Paon, Autruche, Canard, Dindon, Pintade, Aigrette, Faisan etc.
G. Mealy parrot showing powder down, photographed in Florida by Don Kasak.
H. Archaeopteryx sometimesreferred to by its German name Urvogel ("originalbird" or "first bird"), is a genus of theropod dinosaur. Late Jurassic Period (150 million years ago).
I. Shaft of male Indian Peafowl tail feather (Pavocristatus); Feather microstructure showing interlockingbarbules. Photographed by Michael Maggs.
From: 1001 Questions Answered About Birds by Allan D. Cruickshank and Helen G. Cruickshank (Toronto, General Publishing Company, 1958)
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