84 



KEY TO TFIE HIRDS OF KASTEKN iNOHTH AMEUICA. 



SUBFAMILY CYQNIN/E. 

 Swans. 



Bare skin, between the bill and eye ; tarsus, reticulate ; neck, very long ; 

 wing, over 19 inches long. 



General plumage, white ; bill, l)bick willi j-ellow spot (adult) ; distauce from tip of bill 

 to nostril, less tliuii distuiiCK from uostril to eye (immature birdi are gray or brownish !;''iiy)- 

 Common on some parts of the coast. Olar Columbian us. Whistling Swan. 



See No. 13G. 



General plumage, white; lull, black, showing no yellow; distauce from tip of bill to 

 nostril, more than distance from uostril to eye. Chiefly found iu the interior of North America ; 

 not coumion on the coast. Ohiv hucciniitor. Trumpeter Swan. 



See No. 137. 



Olor columbianu 



General plumage, gray, or brownish gray ; birds of this description Tnay be the 

 youiiKof either of the above species, the difference in the distauce from the bill to the eye 

 beiug- ehiiracteristic as in the old birds. 



