Arcana Coelestia #118
118. Verse 14 And the name of the third river is the Hiddekel. This eastwards towards Asshur. And the fourth river is the Phrath.
'The river Hiddekel' is reason or the sharp-sightedness of reason. 'Asshur' is the rational mind. The river's 'going eastwards towards Asshur' means that the sharp-sightedness of reason comes from the Lord by way of the internal man into the rational mind, which belongs to the external man. 'The Phrath' or the Euphrates is knowledge, which is the extremity or boundary.
Fowl
Fowl signify spiritual truth; a bird, natural truth; and a winged thing, sensual truth. Fowl of heaven, as in Hosea 2:18, signify the affections of truth; and reptiles of the earth, the affection of the knowledges of truth and good. Fowl signify thoughts, and all that creeps on the ground, the sensual principle. Fowl signify intellectual things.
(Referencat: Arcana Coelestia 777; Hosea 2)