THE MUTE SWAN. 231 



In Ireland regular visitor to parts of Ulster, Connaught and co. 

 Kerry, and in severe winters more numerous and more general. 



Distribution. — Abroad. — North Russia (Petchora), Kolguev, 

 Novaya Zemlia and arctic Asia, but replaced by slightly larger race 

 in east Siberia. In winter south to British Isles, Norway, Finland, 

 Germany, sometimes to Caspian and Mediterranean, central Asia, 

 casually to Sind. 



CYGNUS OLOR 



287. Cygnus olor (Gin.)— THE MUTE SWAN. 



Anas Olor Gmelin, Syst. Nat., 1, ii, p. 501 (1789 — Russia). 

 Cygnus olor (Gmelin), Yarrell, iv, p. 324 ; Saunders, p. 417. 



Description. — Adult male and female. Winter and summer. — 

 Entire plumage white. This plumage is acquired by a complete 

 moult in autumn ; remiges of both wings are shed together appar- 

 ently before moult of body and tail commences. 



Nestling. — Down on crown, nape, upper-parts and sides of 

 body and uropygial tuft pale greyish-brown, under-parts white. 

 Frontal down in two specimens examined extends slightly further 

 forward than loral down ; down on intercrural space rounded in 

 shape at tip and not extending so far on to bill as in C. cygnus. 



Juvenile. — Crown hair-brown, feathers tipped white ; nape, 

 sides of face and neck whitish intermixed with pale drab-brown 

 feathers, in some nape and sides of neck more or less pale drab ; 

 mantle, scapulars and upper tail-coverts when fresh hair-brown 

 fading to drab, lower scapulars white, more or less suffused pale 

 drab towards tip ; on centre of mantle, back and rump some feathers 

 white more or less suffused pale drab at tip ; chin, throat and fore- 

 neck more or less white, in some suffused palest drab ; sides of body 

 and flanks pale drab ; rest of under-parts white, in some suffused 

 pale drab ; tail-feathers drab shading to whitish at base ; primaries 

 and all secondaries more or less suffused pale drab ; primary-coverts, 

 all wing-coverts and bastard-wing whitish more or less suffused and 

 tipped pale drab, greater coverts with inner webs paler. 



First winter and summer. — Apparently moults in a dark ash- 

 brown head like that of juvenile and acquires a certain amount of 

 new white body -feathers, but very little material examined. 



Second winter and summer. — Probably as adult but not 

 examined. 



Measurements and structure. — £ wing 560-622 mm. (measured 

 with tape, see vol. i, p. *xin), tail 189-198, tarsus 98-120, bill from 

 knob 70-85, middle toe with claw 142-163 (10 measured). $ wing 

 535-570, bill from feathers 73-90 (9 measured) (Schioler). Tail 

 wedge-shaped, 22-24 stiff feathers. Bill as in C. cygnus but upper 

 mandible with a knob at base which becomes much enlarged in 

 spring, is merely a slight protuberance in female and perceptible in 

 juvenile ; culmen without concave depression, nail oblong, small 

 and not nearty occupying whole culmen. Nostrils rather nearer 



