​ADYRMA'CHIDAE (Άδυρμαχίδαι), a people of N. Africa, mentioned by Herodotus as the first Libyan people W. of Egypt. (Herod, iv. 168.) Their extent was from the frontier of Egypt (that is, according to Herodotus, from the Sinus Plinthinetes (ii. 6), but according to Scylax (p. 44, Hudson), from the Canopic mouth of the Nile), to the harbour of Plynos, near the Catabathmus Major. Herodotus distinguishes them from the other Libyan tribes in the E. of N. Africa, who were chiefly nomade (iv. 191), by saying that their manners and customs resembled those of the Egyptians (iv. 168). He also mentions some remarkable usages which prevailed amongst them (l. c.). At a later period they are found further to the S., in the interior of Marmarica. (Ptol.; Plin. v. 6; Sil. Ital. iii. 278, foll., ix. 223, foll.) [ P. S. ]