rrow. He is also greedy of tortoises, and uses the
same method to break their carapaces, eating the soft parts. These
facts have been many times observed by Brehm and other trustworthy
naturalists. It is even said that in Greece every Lammergeyer chooses
a rock on which he always comes to execute the tortoises he has
captured. It was no doubt beneath one of these birds so occupied that,
according to the story, mischance conducted AEschylus.

Neither the beak nor the claws of the Shrike or Butcher-bird (_Lanius
excubitor_) are strong enough to enable him to tear his prey easily.
When he is not too driven by hunger he installs himself in a
comfortable fashion for this carving process, places on a thorn or on
a pointed branch the victim he has made, and when it is thus fixed
easily devours it in threads.

The _Lanius collurio_, an allied bird, uses this method still more
frequently. He even prepares a small larder before feasting. One may
thus see on a thorny branch spitted side by side Coleoptera, crickets,
grasshoppers, frogs, and even young birds, which he has seized when
they were in flight.[28] (Fig. 6.)

[28] Naumann, _Naturgeschichte der Voegel Deutschlands,
etc._, Stuttgart, 1846-53.

[Illustration: FIG. 6.]

Of all these well-attested facts that which perhaps best shows how
animals in certain circumstances may take advantage of a foreign body
to utilise the product of the chase, is the following, the observation
of which is due to Parseval-Deschenes.[29] He followed during several
hours an ant bearing a heavy burden. On arriving at the foot of a
little hillock the animal was unable to mount with his load, and
abandoned it--a very extraordinary fact for one who knows the
inconceivable tenacity of insects. The abandonment therefore left hope
of return. The ant at last met one of his companions, who was also
carrying a burden. They stopped, took counsel for an instant, bringing
their antennae together, and started for the hillock. The second ant
then left his burden, and both together then seized a twig and
introduced its end beneath the first load which had been abandoned
because of its weight. By acting on the free extremity of the twig
they were able to use it exactly as a lever, and succeeded almost
without trouble in passing their booty on to the other side of the
little hillock. It seems to me that these ants who invented the lever
are worthy of admiration, and that their ingenuity does not yie