[13] See a valuable note by D’Arcy W. Thompson prefixed to his translation of the Historia Animalium, Oxford, 1910.
[14] Pliny, Naturalis historia, viii. 17.
[15] Athenaeus, Deipnosophistae, ix. 58.
[16] Aelian, Variae historiae, iv. 19.
[17] The statement of the relation of Callisthenes to Aristotle rests on the somewhat unsatisfactory evidence of Simplicius (sixth century) who states that Callisthenes sent Aristotle certain astronomical observations from Babylon. Simplicius, Commentarii (Karsten), p. 226.
[18] Plutarch, Alexander, lv.
[19] The subject is well discussed by W. Ogle in the introduction to his Aristotle on the Parts of Animals, London, 1882.
[20] The problem of genuineness is discussed in detail by R. Shute, On the history of the process by which the Aristotelian writings arrived at their present form, Oxford, 1888.
[21] I have somewhat abbreviated this and the previous sentence.
[22] De partibus animalium, i. 5; 644ᵇ 21.