BIRDS IN THE CALENDAR 



breeding places of the eider duck, commer- 

 cially the most valuable of all ducks. The 

 nest is robbed of this down once before the 

 eggs hatch out, with the result that the 

 female plucks another store from her own 

 breast, supplemented if necessary from the 

 body of the drake. The sitting bird is then 

 left in peace till the nest has fulfilled its 

 purpose, when the remaining down is likewise 

 removed. This down, which combines 

 warmth and lightness, gives a high market 

 value to the eider, which, throughout Scan- 

 dinavian countries is strictly protected by 

 law and even more effectually by public 

 opinion. 



The majority of ornamental ducks inter- 

 breed freely in captivity. Those who, ap- 

 parently on reliable evidence, distinguish 

 between the polygamous habit in tame ducks 

 and the constancy of the mallard and other 

 wild kinds to a single mate have hastily 

 assumed that such hybrids are unknown in 

 the natural state. This, however, is incorrect, 

 as there have been authentic cases of crosses 

 between mallard and teal, pochard and scaup 

 and other species, such hybrids having at 

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