48 THE BOOK OF A NATURALIST 
inches of my face, to remain there suspended 
motionless like a hover-fly on misty wings that 
produced a loud humming sound; and when thus 
suspended, it has turned its body to the right, then 
to the left, then completely round as if to exhibit 
its beauty—its brilliant scale-like feathers changing 
their colours in the sunlight as it turned. Then, 
in a few seconds, its curiosity gratified, it has 
darted away, barely visible as a faint dark line in 
the air, and vanished perhaps into the intricate 
branches of some tree, a black acacia perhaps, 
bristling with long needle-sharp thorns. 
The humming-bird is able to perform this feat a 
hundred times every day with impunity by means 
of its brilliant vision and the exquisitely perfect 
judgement of the brilliant little brain behind the 
sight. But I take it that if the bird had attempted 
the feat of the bat it would have killed itself. 
It is a rule in wild life that nothing is attempted 
which is not perfectly safe, though to us the action 
may appear dangerous in the extreme, or even 
impossible. At all events, I can say that these 
bats in a Selborne Jane taught me more than all 
the books—they made me see and understand the 
perfection of that extra sense. 
But it is just that same sense which Spallanzani 
and Cuvier wrote about, and we cannot but think 
that the bat has something more than this. That 
peculiar disposition of glands and nerves on the 
wings, the enormous size of the ear in the great- 
eared bat, the ear-leaf, and leaf-nose, and the other 
