EYES AND NO EYES 41 
try again, but all to no purpose ; then, just as we are 
leaving, the birds flit up on one side of us, and we are 
baffled. 
If any one of our readers will visit the New 
Natural History Museum at South Kensington, in 
the fine room filled with splendid cases of British 
birds he will find a case of dotterels and their young 
on some beach shingle. They are perfect in their 
setting up, even in the most minute details. When 
looking at these he will see at the first glance what I 
have endeavoured to explain here ; and that is why 
dotterels and their young are invisible on shingle. 
