THE WIGEON. 295 



Measurements and structure. — $ wing 254-270 mm., tail 95- 

 108, tarsus 35-40, bill from feathers 33-36 (12 measured). $ wing 

 236-255, bill 31-34. Primaries : 1st narrow, pointed and about 

 half longest primary-covert, 3rd longest, 2nd equal or 2-4 mm. 

 shorter, 4th 11-14 shorter, 5th 25-29 shorter, 6th 40-45 shorter ; 

 2nd emarginated inner and 3rd outer webs. Innermost secondaries 

 moderately long and pointed and between 6th and 7th or 7th and 

 8th primaries ; in eclipse less pointed at tip. Scapulars elongated 

 and tapering to an obtuse point ; in eclipse with rounded, almost 

 square, tips. Tail short, rounded, 14 feathers, central pair tapering 

 sharply to a point and projecting beyond rest ; in eclipse less 

 pointed and only slightly projecting. Bill smaD, rather narrow, 

 shorter than head, edges parallel nearly to tip where they gradually 

 converge to form a rounded tip, lamellae of upper mandible almost 

 concealed. 



Characters and allied species. — No subspecies. For differences 

 of A. americana see under that species. From other British ducks 

 adult male distinguished by dark mouse -grey and white vermicu- 

 lated upper-parts, black and green speculum and white wing- coverts, 

 adult and juvenile females have speculum blackish or partly 

 metallic -green, only one inner secondary with outer web white and 

 greater coverts with hardly any black (distinction from Gadwall). 

 Juvenile male' has speculum blackish usually with a little green, 

 median coverts with no chestnut, greater coverts with hardly any 

 black (distinction from juvenile Gadwall). 



Field -characters. — At close quarters male is unmistakable, 

 whilst golden fore -head and crown — creamy- white in a strong light 

 — identifies him at a distance too great for chestnut head and neck, 

 vermiculated grey back and flanks, and black under tail-coverts 

 with pure white area in front of them to be seen plainly. Female, 

 intermediate in size between Mallard and Teal is of slighter build 

 than either, and differs further in short bill, pointed tail, general 

 rufous tints and grey under tail -coverts. On the wing white 

 abdomen of both sexes, large white shoulder-patch of male, and 

 conspicuous double white wing-bar of female, coupled with slender 

 build are good characters. Out of breeding-season is usually seen on 

 coast, congregating, sometimes in thousands, on muddy shores and 

 estuaries, especially where Zostera abounds, but a good many winter 

 on inland waters. Call of male a loud and sudden " whee-ou," of 

 female a purring growl. 



Breeding-habits. — Nests on moorlands and rough pastures. 

 Nest. — Often in heather quite close to streamlet, or in wiry grass 

 close to water, lined with some grass or heather stalks and down 

 (feathers from nest, see Brit. B.,II, PL 1.). Eggs. — Usually 7-8, 

 but 9 and 10 on record, creamy and fine grained. Average of 

 117 eggs, 54.7x38.7. Max.: 59.5x38.5 and 58x41. Min. : 

 49.9x35.2 mm. Breeding -season. — During second half May in 



