THE FERRUGINOUS DUCK. 319 



Adult female. Winter. — Crown bay ; nape, mantle and 

 scapulars black-brown or sepia tinged olive, feathers mostly edged 

 russet and slightly freckled same ; back, rump and upper tail- 

 coverts as male ; cheeks and sides of neck auburn shading to russet 

 on throat and fore -neck ; chin usually with a white spot ; upper - 

 breast drab-brown or black-brown, feathers fringed deep russet or 

 white tinged russet (in some tipped bay) ; flanks, sides of body and 

 sides of vent dusky-brown or drab-brown, feathers shaded and edged 

 russet or buff-brown ; rest of breast white, some feathers with im- 

 perfectly concealed drab bases ; remaining under-parts, tail and 

 wings as in male. Summer. — No spring material examined. Colour 

 of head and neck appears to be less rich, upper-parts with no 

 f recklings and throat more or less intermixed with white, which may 

 be due to abrasion. 



Nestling. — Crown, nape, mantle, back, uropygial tuft and 

 sides of body warm sepia, down with golden-brown tips ; wing-bar, 

 patch on either side of mantle and at base of uropygial tuft pale 

 yellow ; eye-stripe, cheeks and sides of neck, chin, throat and upper- 

 breast pale yellow ; belly pale yellow intermixed with warm sepia • 

 vent and thigh all round more or less warm sepia. 



Juvenile. Male and female. — Like adult winter female but 

 distinguished by mottled appearance of under-parts. Upper-parts 

 as in adult winter female but feathers of crown black-brown with 

 bay tips ; nape ash-brown or drab-brown ; cheeks, sides of neck, 

 chin, throat and fore-neck dusky-brown, feathers tipped auburn (in 

 some white chin-spot absent and chin and throat ashy- white, 

 feathers tipped pale auburn) ; sides of body, flanks, and vent as in 

 adult female ; under tail-coverts white irregularly barred or marked 

 brown ; rest of under-parts drab, feathers edged white or pink-buff 

 (some feathers of breast tipped russet) giving under-parts a mottled 

 appearance ; tail and wing as adult female. 



First winter and summer. Male. — As adult winter-summer 

 male but median coverts generally browner and more worn. The 

 juvenile body -feathers, tail and innermost secondaries and coverts 

 are moulted Oct. to Feb. but not rest of wings ; sometimes some 

 juvenile body-feathers are retained. Female. — Probably as adult 

 female and moult as in male but no material examined. 



Measurements and structure. — $ wing 174-192 mm., tail 48-58, 

 tarsus 29-31, bill from feathers 40-43 (12 measured). $ wing 176- 

 185, bill 36-40. Primaries : 1st narrow, pointed and about half 

 longest primary- covert, 2nd and 3rd equal and longest (3rd some- 

 times slightly shorter than 2nd), 4th 3-8 mm. shorter, 5th 14-16 

 shorter, 6th 22-28 shorter. Bill shorter than head, slightly broader 

 at tip than at base, culmen less abruptly concave. Other structure 

 as in N. f. ferina. 



Soft parts. — Bill (ad. <J) greenish-black, greyer at tip and along 

 cutting edge, under mandible horn-brown, (ad. $) blackish-lead, 

 greyer at tip and along cutting edge, under mandible as in male,, 



