24 



rated by black throat stripe or mottling Cackling Goose. 



9. Lower parts light brownish gray, fading gradually into white on anal 



region; white cheek patches usually confluent on. throat (10) 



10. Larger, 35 to 43 inches long Canada Goose. 



10. Smaller, 25 to 34 inches long Hutchins Goose. 



11. Bill nearly cylindrical, about as wide as high throughout; head always 



more or less crested (12) 



11. Bill always wider than high near the tip; head rarely crested (14) 



12. Smaller; wing 7 to SJ inches long; crest high and flattened 

 sidewise Hooded Merganser. 



12. Larger; 8£ to 11% inches long; crest inconspicuous (13) 



13. Wing about 10J inches long; frontal feathers extending beyond those 



on side of bill American Merganser. 



13. Wing about 9 inches long; frontal feathers not extending beyond those 



on side of bill Red-breasted Merganser. 



14. Hind toe with a rounded membranous lobe (15) 



14. Hind toe without a lobe-like border (27) 



15. Wing 7 inches or less in length (16) 



15. Wing over 7 inches long , (17) 



16. Upper tail-coverts very short ; bill broad; tail flat. Ruddy Duck. 



16. . Upper tail-coverts about half as long as tail; head fluffy. . . 



-. Buffle-head. 



17. Bill appendaged with a lobe at base formed of skin of cheeks; culmen 



about one inch long Harlequin Duck. 



17. Bill bulging at base; nail large and so united with the bill as to give 



the nail a very indistinct outline . (18) 



17. Bill of the usual duck form (20) 



18. Wing 10J inches long or more; a white wing patch in both 

 sexes White-winged Scoter. 



18. Wing, less than 10J inches long (19) 



19. Feathers on the culmen reaching forward as far as those on sides of 



upper mandible American Scoter. 



19. Feathers on the culmen reaching about an inch farther forward than 



those on side of upper mandible Surf Scoter. 



20. Tail pointed (over 6 inches long, male; about 3 inches long, 

 female ;) bill black and orange, nostril within less than \ inch 

 of frontal feathers '. Old-squaw Duck. 



20. Tail not pointed ; nostril about J inch from frontal feathers . . (21) 

 21. Bill high at base (over half as high as long) ; under tail-coverts white(22) 

 21. Bill lower at base; under tail-coverts dark (23) 



22. Male with the gloss of the dark head and throat green; head of 

 female brown Golden-eye. 



22. Male with the gloss of the dark head and throat purple; head 



of female brown Barrow Golden-eye. 



23. . Bill decidedly wider near tip than at base (24) 



23. Bill but little if any wider at tip than at base (26) 



