Book 2

λέγει δὲ Ἀριστοτέλης τῶν ζῴων τὰ μὲν ζῳοτόκα εἶναι, τὰ δὲ ᾠὰ τίκτειν, τὰ δὲ σκώληκας· καὶ ζῷα μὲν ἀνθρώπους γεννᾶν καὶ τὰ λοιπὰ ὅσα τριχῶν ἐστιν ἐπήβολα, καὶ τὰ κητώδη τῶν ἐνύδρων· τούτων δὲ τὰ μὲν αὐλόν, βράγχια δὲ οὐκ ἔχειν, οἷον δελφῖνα καὶ φάλαιναν.