The balæna penetrates even to our seas. It is said that they are not to be seen in the ocean of Gades before the winter solstice, and that at periodical seasons they retire and conceal themselves in some calm capacious bay. This fact, however, is known to the orca, an animal which is peculiarly hostile to the balæna, and the form of which cannot be in any way adequately described, but as an enormous mass of flesh armed with teeth. This animal attacks the balæna with its young, in its places of retirement, and as they turn to defend themselves, it pierces them just as though they had been attacked by the beak of a Liburnian galley. The balænæ, devoid of all flexibility, without energy to defend themselves, are well aware that their only resource is to take to flight in the open sea and to range over the whole face of the ocean; while the orcæ, on the other hand, do all in their power to meet them in their flight, throw themselves in their way, and either kill them cooped up in a narrow passage, or else drive them on a shoal, or dash them to pieces against the rocks. When these battles are witnessed, it appears just as though the sea were infuriated against itself; not a breath of wind may be felt in the bay, and yet the waves by their pantings and their repeated blows will be heaved aloft in a way which no whirlwind could effect. [Illustration: RORQUAL.—_Physalus Böops._] [Illustration: SPERMACETI WHALE.—_Cátodon Macrocéphalus._] An orca has been seen even in the port of Ostia, where it was attacked by the Emperor Claudius. While he was constructing the harbor there, an orca came, attracted by some hides brought from Gaul, which had happened to fall overboard there. Feeding upon these for several days it had quite glutted itself, and hollowed out a channel in the shoal water. Here, the sand was thrown up by the action of the wind to such an extent, that the creature found it quite impossible to turn round; and while in the act of pursuing its prey, it was propelled by the waves towards the shore, so that its back came to be perceived above the level of the water, very much resembling in appearance the keel of a vessel turned bottom upwards. Upon this, Cæsar ordered a great number of nets to be extended across the mouth of the harbor, from shore to shore, while he himself went there with the prætorian cohorts, affording a spectacle to the Roman people; for boats assailed the monster, while the soldiers on board showered lances upon it. I myself saw one of the boats sunk by the water which the animal, as it respired, showered down upon it. CHAPTER IV. DOLPHINS.