According to a fragment of Artemidorus, cited by Stephanus (s. v. Ὠστίωνες
), the Ostiones were a people on the Western Ocean, who were also called Cossini by Artemidorus, but Ostiaei by Pytheas.
It seems probable, that these Ostiones or Ostiaei are the Osismii of Caesar. (B. G.
2.34.) Walckenaer, who is ingenious on such obscure names, does not admit that these Cossini are the same as the Ostiaei, but he assumes them to be a neighbouring tribe at the western extremity of Bretagne.
There is a place Coesnou