DrCKS, GEESE AND SWANS OF NORTH AMEKlflA. 



91 



Subfamily CYGNIN^E. Swans. 



Genus OLOR Wagler. 



OLOR COLUflBlANUS (On/.). 



Whistling Swan. 



Adult: (JiMioral i>lviiiianp, wliilc; bill and feet, lilaek ; a small yellow spot on bare loral 

 skin at the base of the bill in front of the eye, which is not always present ; iJie di.itifm-r /mm 

 tJif'.froiil nnijlc of Uic ojc lo Ihc hack edije of thr iioalril is more Ihoii Ihi' distiince from the huck rdijr 

 of the no.itril to the and of thi- hill ; this is one of the characters hy whieli it may he always ilis- 

 tiiiouislied from the Trumpeter Swan; bill and feet, black. 



Olor Ctiluinbianus. 



The immature birds are usually pale, plumlieous g'ray, with a brownish wash ou the head 

 and ujiper neck; feet, pale yellowish, sometimes pale flesh color or o'l'ayish. 



I.(Uigth, 58; wing, 21.50; liill, 4; tarsus, 4.20. 



Ilnhitat : " The whole of Xorth America, breeding- tar north, < oiiiniander Islands, Kam- 

 chatka, accidental in Scotland."" (A. (). V .) 



