VOL. XV.] SURFACE-FEEDING DUCKS. 137 



Male. — Down. First juvenile plumage. This in the 

 Wigeon is more variable than in other surface-feeding ducks, 

 some specimens showing some barring on the back between 

 the shoulders, others none, some having a glossy green, 

 others a blackish speculum, some showing a uniform greyish- 

 brown fore-wing, others having the lesser and median coverts 

 broadly edged with white, and others again even showing 

 a tendency towards a white fore-wing with darker edges to 

 the feathers. 



From the first juvenile plumage the bird passes by a 

 slowly progressing moult, into its first nuptial plumage. 



During this moult there is a growth of feathers which are 

 mostly shed again and which are evidently representatives 

 of a lost second juvenile plumage. 



The first nuptial plumage is like the corresponding plumage 

 of the old male, except that the yellowish feathers of the 

 fore-head are as a rule paler, the vermiculation of the back 

 and flank feathers seems slightly coarser and the juvenile 

 fore-wing with the above named variations is retained. As 

 it is uncertain whether males always pair in this plumage 

 — those dissected have shown swelling of the sexual organs, 

 although apparently not to the extent shown in old males — 

 this plumage might even be called third (or existing second) 

 juvenile plumage. It is followed in summer by a first post- 

 nuptial eclipse or reversion plumage showing for the first 

 time the white fore-wing, and this again is replaced by the 

 nuptial plumage of the fulty adult male, the white fore-wing 

 being retained. 



(Number of specimens examined : Coll. E.L.S., 373. 

 Univ. Zool. Mus., Copenhagen, 85.) 



It will be noticed that the females of all the above-named 

 species have a post-nuptial or eclipse plumage as well as the 

 males, but as it has only been my intention to give an account 

 of the sequence of plumages no detailed description of these 

 or other plumages has been attempted nor have such well- 

 known changes as that of the colour of the feet, due to age, 

 or the seasonal colour changes in the bills been mentioned. 

 Besides, a full description of all these plumages with the 

 necessary illustrations is under preparation and will appear 

 in a not remote future. 



Finally it may be mentioned that a few females in male-like 

 plumage have been seen. 



On the 13th and 20th of March, 1911, two ten-months-old 

 Mallard females were killed. With a lot of others they had 

 been reared by a hen, the eggs having been taken from the 



