THE HARLEQUIN-DUCK. 351 



Soft parts. — Bill (<$ ad.) bluish lead-grey, nail paler, ($ ad.) 

 duller ; legs and feet (^ ad.) pale bluish, webs dusky, claws whitish, 

 ($ ad.) dull bluish-grey ; iris (ad. <$) reddish-brown, (ad. $) brown. 



Characters and allied forms. — H. h. pacificus (N.E. Siberia to 

 western N. America) has stronger bill, higher at base and usually 

 broader, but females cannot always be distinguished with certainty. 

 Dark plumbeous upper-parts, head and body with numerous white 

 patches and steel-blue speculum distinguish adult males, brown of 

 adult female and juveniles with white marks on head and small 

 size distinguish them from other British ducks. 



Field -characters. — Drake easily identified ; vivid white streaks 

 on neck and breast, and chestnut flanks, showing conspicuously 

 even in poor light. Duck easily confused with females of Long- 

 tailed and BufTel-headed Ducks. From these it may be distin- 

 guished by having two distinct white patches between eyes and 

 base of bill. Apart from plumage, following points are aids : short- 

 ness of bill (equally noticeable, however, in Long-tailed Duck), 

 extreme buoyancy, habit of keeping apart from other species, and 

 — most characteristic — manner of swimming, either so closely 

 abreast that flank of each individual touches that of its neighbour, 

 or in step-like formation, manoeuvre executed with wonderful pre- 

 cision and at once distinguishes species. Always in small parties, 

 seldom exceeding eight individuals. Frequently utters low piping 

 whistle when feeding or about to take wing. Dives in about two 

 fathoms and has its favourite feeding-grounds, usually off end of 

 particular ledge of rock. Duration of dive seldom exceeds 28 

 seconds. (C. E. Alford.) 



Breeding -ha bits. — Somewhat sociable, several pairs nesting to- 

 gether. Nest. — Usually on island in stream, in hollow, sheltered 

 under brushwood, rocks, etc., and lined with greyish down. Eggs. — 

 5 to 10, smooth, creamy or cinnamon-buff. Average of 60 eggs. 

 57.6x41.7. Max.: 61 x 42.5 and 59 X 44. In. : 52x39 and 54x 

 38.7 mm. Breeding-season. — Rather late, from mid-June to mid- 

 July in Iceland. Incubation. — By female only. Period stated as 

 3J weeks. Single brooded. 



Food. — In Iceland mainly larvae of Ephemeridse and Phryganeidse 

 during summer ; also mollusca (Littorina), Crustacea and spawn. 

 Millais also records worms, small fish, insects. Faber mentions 

 Nerita and Cancer pulex. In Alaska mussels (Mytilus edulis). 



Distribution. — Great Britain. — Very rare vagrant. Male found 

 dead Filey (Yorks.) autumn 1862. Two young males obtained, out 

 of three seen, Fame Isles (Northumberland) Dec. 2, 1886 (J. G. 

 Tuck, Zool, 1887, p. 70, H. Saunders, P.Z.S., 1887, p. 319), a third 

 obtained (G. Bolam, Birds Northumberland, etc., p. 401) is an adult 

 male and date of its capture is rather uncertain (W. Percy in litt.). 

 Has possibly occurred Scotland, while others recorded are doubt- 

 fully authentic (Saunders, p. 457). 



