Page:1888 Cicero's Tusculan Disputations.djvu/309

 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-fish, and when they are digested by the heat which exists in the stomach, they cast them up, and then pick out what is proper nourishment. The sea-frogs, they say, are wont to cover themselves with sand, and moving near the water, the fishes strike at them, as at a bait, and are themselves taken and devoured by the frogs. Between the kite and the crow there is a kind of natural war, and wherever the one finds the eggs of the other, he breaks them. But who is there who can avoid being struck with wonder at that which has been noticed by Aristotle, who has enriched us with so many valuable remarks? When the cranes pass the sea in search of warmer climes, they fly in the form of a triangle. By the first angle they repel the resisting air; on each side, their wings serve as oars to facilitate their flight; and the basis of their triangle is assisted by the wind in their stern. Those which are behind rest their necks and heads on those which precede; and as the leader has not the same relief, because he has none to lean upon, he at length flies behind that he may also rest, while one of those which have been eased succeeds him, and through the whole flight each regularly takes his turn. I could produce many instances of this kind; but these may suffice. Let us now proceed to things more familiar to us. The care of beasts for their own preservation, their circumspection while feeding, and their manner of taking rest in their lairs, are generally known, but still they are greatly to be admired. L. Dogs cure themselves by a vomit, the Egyptian ibis by a purge; from whence physicians have lately—I mean but few ages since—greatly improved their art. It is