42 BRITISH BIRDS. [vol. ix. 



First eclipse. — Probably as adult eclipse, but the details 

 of moult, which from absence of material I am unable to 

 furnish, are possibly different. 



Second winter. Male awl fetnale. — Not distinguishable 

 from the adults and the moult is probably the same. 



The Genus NY BOCA. 



The sequence of plumages and moults in the genus 

 Nyroca appears to be very similar to that of the surface- 

 feeding ducks, but I do not propose to deal in full A\ith 

 it at present, beyond stating that female Pochard, Tufted 

 Duck, and apparently Scaup, have as complete a spring- 

 moult as do the female surface-feeding ducks, and also 

 acquire just before breeding commences a special " nest " 

 doMn in addition to the ordinary do^\n, A\hich is also 

 rene\Aed at this time. In the Pochard the ordinary' down 

 is ashy-giey or light ashy-brown, the " nest '" down is 

 black ; in the White-eyed Pochard the ordinaiy down is 

 pale a-hy, the " nest '" down black-brown, buffy- white 

 towards the tip ; in the Tufted Duck the ordinary down 

 is ashy-lirown, the " nest " down black, broAAnish-black 

 tow aids the tip ; in the Scaup the ordinary do\\ n is 

 ashy-brown, the "nest" down black. 



In conclusion I wish to thank Lord Rothschild, the 

 authorities of the Natural History Museum, South 

 Kensington, and Mr. H. F. Witherby, for kindly 

 permitting me the use of their collections. 



