BRITISH BIRDS OF FASTEST FLIGHT 31 
Colonel Meinertzhagen, whilst agreeing that 
the heavier bird of similar type is the faster flier 
once it gets going, has kindly sent me the follow- 
ing observations on the foregoing statements as 
to the pochard and mallard. " The common 
pochard is not a bird of ' similar type ' to a 
mallard, the one being a diving duck and the 
other surface-feeding. They differ in the propor- 
tion of wing area to body weight, also in bone 
structure. The pochard and all diving duck, 
probably fly faster than surface - feeding duck 
under similar conditions, having heavier bodies in 
proportion to the wing area than is ever found 
among surface-feeding duck. The eider duck, 
which is even heavier than the ordinary diving 
duck {Nyroca), probably flies faster than them all 
when once started." 
4. There must he a standard length oj flight to 
which the test is to he ajyplied. 
If the question were asked, " Who is the 
faster runner, A or B ? " the reply would surely 
be " To what distance are you referring? " A 
short or a long distance ? Applying the analogy, 
it is obvious that a bird might be much faster 
than another for a short distance, but if the 
