the English Leptus autumnalis. It is so small that, notwithstanding its
bright scarlet colour, it can only be discerned by bringing the eye
close to it; and being, moreover, exceedingly active and abundant in all
shady places in summer--making life a misery to careless human
beings--it must be very much more dangerous to birds than the larger
sedentary Ixodes. The bete-rouge invariably lodges beneath the wings of
birds, where the loose scanty plumage affords easy access to the skin.
Domestic birds suffer a great deal from its persecutions, and their.
young, if allowed to run about in shady places, die of the irritation.
Wild birds, however, seem to be very little troubled, and most of those
I have examined have been almost entirely free from parasites. Probably
they are much more sensitive than the domestic birds, and able to feel
and pick off the insects with their beaks before they have penetrated
into the skin. I believe they are also able to protect themselves in
another way, namely, by preventing the parasites from reaching their
bodies at all. I was out under the trees one day with a pet oven-bird
(Furnarius rufus), which had full liberty to range about at will, and
noticed that at short intervals it went through the motions of picking
something from its toes or legs, though I could see nothing on them. At
length I approached my eyes to within a few inches of the bird's feet,
and discovered that the large dry branch on which it stood was covered
with a multitude of parasites, all running rapidly about like foraging
ants, and whenever one came to the bird's feet it at once ran up the
leg. Every time this happened, so far as I could see, the bird felt it.
and quickly and deftly picked it off with the point of its bill. It
seemed very astonishing that the horny covering of the toes and legs
should be so exquisitely sensitive, for the insects are so small and
light that they cannot be felt on the hand, even when a score of them
are running over it; but the fact is as I have stated, and it is highly
probable, I think, that most wild birds keep themselves free from these