also given these beasts appetite and
sense; in order that by the one they may be excited to procure
sufficient sustenance, and by the other they may distinguish what is
noxious from what is salutary. Some animals seek their food walking,
some creeping, some flying, and some swimming; some take it with their
mouth and teeth; some seize it with their claws, and some with their
beaks; some suck, some graze, some bolt it whole, and some chew it.
Some are so low that they can with ease take such food as is to be
found on the ground; but the taller, as geese, swans, cranes, and
camels, are assisted by a length of neck. To the elephant is given a
hand,[223] without which, from his unwieldiness of body, he would
scarce have any means of attaining food.

XLVIII. But to those beasts which live by preying on others, nature has
given either strength or swiftness. On some animals she has even
bestowed artifice and cunning; as on spiders, some of which weave a
sort of net to entrap and destroy whatever falls into it, others sit on
the watch unobserved to fall on their prey and devour it. The naker--by
the Greeks called _Pinna_--has a kind of confederacy with the prawn for
procuring food. It has two large shells open, into which when the
little fishes swim, the naker, having notice given by the bite of the
prawn, closes them immediately. Thus, these little animals, though of
different kinds, seek their food in common; in which it is matter of
wonder whether they associate by any agreement, or are naturally joined
together from their beginning.

There is some cause to admire also the provision of nature in the case
of those aquatic animals which are generated on land, such as
crocodiles, river-tortoises, and a certain kind of serpents, which seek
the water as soon as they are able to drag themselves along. We
frequently put duck-eggs under hens, by which, as by their true
mothers, the ducklings are at first hatched and nourished; but when
they see the water, they forsake them and run to it, as to their
natural abode: so strong is the impression of nature in animals for
their own preservation.

XLIX. I have read that there is a bird called Platalea (the shoveller),
that lives by watching those fowls which dive into the sea for their
prey, and when they return with it, he squeezes their heads with his
beak till they drop it, and then seizes on it himself. It is said
likewise that he is in the habit of filling his stomach with
shell-f