PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 187 



J"ig. 12. 



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Cygnus gihbus. 



Fig. 13. _,./' 



of the middle part of the Beck are conspicuously lighter brown, be- 

 coming almost white above towards the limit of the white part of the 

 neck. Besides, the middle tail feathers are brownish gray on the inner 

 web tOAvards the tip; this color on the outer ones also extending into 

 the outer web, which, however, is edged with white to the very tip; the 

 shafts are brown. 



In specimen No. 6GG05, U. 8. Wat. Mus., which has the knob still very 

 small, viz, only 3™"% the plumage has already 

 become pure white, without any trace of brown 

 shadings or spots, the same being the case in 

 iV^o. 2, Mus. Leid., in which the height of the 

 tubercle only amounts to S'"'". 



The doicny xilumage is white. The following ' 

 dimensions and descriptions are from two 

 cygnets hatched in the Zoological Garden in 

 Eotterdam: ' '^- ^",...../ O 



Mus. Leiden. (9 FuUus, 34 days old.) 



Length of bill along gape oG«>™, from tip to 

 fore border of the nostrils 20"^™, to tbe eye 

 55"'™, lireadth 12'""\ Length of toes with 

 claw: outer toe 43, middle toe 44, inner toe 

 34, and hind toe 10'"™. Tarsus, oo""'"'. 



Pure white; the down of the upper parts is 

 gray at the base, giving the upi)er surface a 

 faint grayish tinge. Bill lead-black, with the nail light. Legs yellow- 

 ish gray, with the webs grayish yellow. 



Mus. Leiden. ( i Pullus, 1 day old.) 



Length of commissure 21""^^ bill from tip to the nostrils 12, to the 

 eye 30""", breadth of bill 8"^"^. Length of toes with claw: outer toe 29, 

 middle toe 31, inner toe 24, hind toe C, and tarsus 23"^"*. 



Pure white; the grayish tinge on the upper surface almost impercep- 

 tible. 



As may be seen by reference to fig. 13, ahnost the whole of the base 

 of the bill in this species is covered with down, which reaches much 

 more than half way to the nostrils, both above and below, and having 

 a very diflerent anterior outline from the same stage of species of Cyg- 

 nus and Olor, as shown in figs. 12 and 14. 



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Olor Columbia nils. 



