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THE ZOOLOGIST. 



descriptions without its being blown away. The best method to 

 hold the down is against a very dark background two or three 

 feet away, when with a three-power pocket-lens the colour and 

 construction can be carefully observed and noted. The pbcket- 

 lens suits much better than a microscope, which I found too 

 powerful, giving too small a field ; besides, putting the down 

 between glass slips takes away from the natural shape and 

 colour. 



I find in Sharpe's ' Handbook of British Birds ' a fair de- 

 scription of each down — probably in bulk — given after his note 

 about the nest and eggs. The same is also given in Seebohm's 

 ' Eggs of British Birds,' but not so good. I hope Mr. Dresser, 

 in his new book, ' The Eggs of the Birds of Europe ' — a work in 

 which the three-colour process of photography has been so suc- 

 cessfully applied to eggs — will make some attempt to adopt this 

 beautiful printing to the Duck's down when he comes to describe 

 their eggs. 



I have included below downs of Mute Swan and Canada 

 Goose, both found wild about here. I believe — at a lake in 

 this neighbourhood — the keepers have tried without success to 

 frighten away and shoot this latter species ; it was, of course, 

 originally introduced. 



Descriptions of Downs. 



Sommerfeldt's Method. 



Tadorna cornuta. — A large white 

 down loosely put together, with a 

 very white centrum. Rami long and 

 thin, with radii medium length, 

 getting shorter as they approach 

 the tip, where they lie much closer, 

 and form into a hair-like ending ; 

 through the glass this appears to 

 be made up of gradually shorten- 

 ing fine radii. (See Class A, No. 1.) 



Cygnus mutus. — Down very large, 

 all pure white ; rami long ; radii 

 fairly short, lying close, and not 

 getting much shorter towards the 

 tip, as in Sheld-drake. (See Class 

 A, No. 2.) 



In Bulk. 



A. White Down. 



1. Sheld-drake. — Down large and 

 loose, of a dull grey white, im- 

 possible to pick out centres, which 

 only seem a little whiter. 



2. Mute Swan. — Down very large, 

 not unlike No. 1, but tips not so 

 fine ; it is whiter. 



B. White-tipped Downs. 



1. Mallard. — Down dark brown, 

 with fairly large white centres ; 

 the tips quite distinct, whitish 

 brown ; the down generally not 

 compact, but feathery. 



2. Bed-breasted Merganser. — This 

 down is light greyish brown, with 



