The Crocodile was considered a sacred animal by the ancient Egyptians. In ruins of temples mummies of Crocodiles are still found in a perfect state of preservation. The Romans introduced living Crocodiles at the national games in the Colosseum. At first only five were imported under the ædileship of Scaurus. Under the Emperor Augustus thirty-six were killed in the Circus of Flaminius. Several ancient medals represent this reptile, the body of which perfectly resembles that which now lives in the waters and on the banks of the Nile. There is a truly wonderful fact in the natural history of the Crocodile. Listen to what Herodotus, the father of history, tells us with regard to it:--"When the Crocodile takes his food in the Nile, the interior of its mouth is always covered with _bdella_ (flies). All birds, with one single exception, flee from the Crocodile; but this one, the Nile Bird, _Trochylus_, far from avoiding it, flies towards the reptile with the greatest eagerness, and renders it a very essential service. Every time the Crocodile goes on shore to sleep, and at the moment when it lies extended with open jaws, the Nile Bird enters the mouth of the terrible animal and delivers it from the _bdella_ which it finds there; the Crocodile shows its recognition of the service, and never harms the bird." This fact, reported by Herodotus, was long considered to be a fable, but the naturalist, Etienne Geoffroy Saint-Hilaire, who formed part of the commission that General Bonaparte took with him in his expedition into Egypt, had on several occasions opportunities of proving the truth of the historian's narrative.