3. A physician of Alexandria, who wrote a comprehensive medical work entitled , " Man," in which he treated of diseases in a systematic order, beginning with the head, and descending to the feet, and also of pharmacy. As Photius calls him (Biblioth. § 220) by the title of "Archiater," he must have lived after the beginning of the Christian era; and as Galen does not mention him, he may be supposed to have lived later than the second century. If (as is not improbable) he is the same physician, one of whose medical formulae is quoted by Aetius (1.3. 58. p. 127), he must have lived before the sixth century. Haller places him in the reign of Theodosius, that is, in the fourth century (Bibl. Medic. Pract. vol. i. p. 287), which may be quite correct, but he does not state the reason for his assigning so precise a date.

Theon, the commentator on Nicander mentioned by Stephanus Byzantinus (s. v. Κορώπη), is reckoned as a physician by Fabricius (Bibl. Gr. vol. xiii. p. 434) and Haller (l.c. p. 138), but it is perhaps more probable that he was a grammarian by profession, as he appears to have written a commentary also on Apollonius Rhodius and on Lycophron.