In the long stretch of Aerial coastline bounding the Mare Icarium, which sweeps with the curve of a foretime beach from the Hammonis Cornu to the tip of the Edom Promontory, there stand halfway down its far-away seeming sea-front two little nicks or indentations. Even in poor seeing they serve to darken this part of the coast while in good definition they come out as miniature caret-like bays. They are the Portus Sigaei, and mark the spots where the Phison and the Euphrates respectively leave the coast. About four degrees apart, the eastern makes embouchure to the original Phison, the western to the original Euphrates, and each in some mysterious manner is associated not only in position but in action with the canal itself. In the single state each canal leaves the Mare from this its own caret, the Phison proceeding thence northeast down the disk, the Euphrates nearly due north, so that starting four degrees apart at the south they are forty degrees asunder at their northern termini. Clearly at these latter points they are not even neighbors, and except for the accident of close approach at their other ends have nothing in common anywhere. And yet when gemination takes place a curious thing occurs: each borrows its neighbor’s terminal as departure-point for its own duplicate canal. Having thus got its base the replica proceeds to parallel its own original canal without the least reference to the other canal whose own caret it has so cuckoo-wise appropriated. What the Phison thus does to the Euphrates, the Euphrates returns the compliment by doing to the Phison. In this manner is produced an interrelation which suggests, without necessarily being, an original community of interest; suggests it on its face and yet appears to be rather of the nature of an adaptation to subsequent purposes of a something aboriginally there. [Illustration: _Mouths of Euphrates and Phison._ _June. 1903._]