96 VERTEBRATES: BIRDS. 



the North. Eider-down is obtained from the nests of 



Fig. 159. Canvas-Back. 



Eider Ducks, the birds having plucked it from their 

 breasts to place around their eggs. 



ALBATROSSES AND PETRELS. 



The Albatrosses are the largest of web-footed birds ; 



Fig. 160. Sooty Albatross. 



