Sserrinae

Body

Black above and hard yellow below, with the two short arms high on the body that let a Sserrin work a rope and a knife, and the flank pits that read a hull's tonnage from a mile off in the dark. They can go a month without touching anything solid, taking their water from the fish they eat and sleeping adrift on the surface with a third of the lung inflated.

The hard yellow belly is the one colour in the species meant to be seen from above by something with better eyes than theirs, and a Bright Belly turning its underside up in the water is a signal that predates the cord and still means the same thing, which is that a bargain is open.

Society

Everything the lines do above water is done by this strain. They carry the cord in and out, they announce each alteration of the knot by swimming into a harbour and shouting it at the wall, and they take payment in metal, salt, glass and news. In air they are close to deaf like all their people, which is why the shouting is shouting, and why ports think of them as rude.

They keep the taboo of the cut cord, which is the one crime the lines execute for, and the oath on breath, sworn from under water and affirmed on surfacing.

Faith

Orruthaan in his surface face, the Weight Below as felt from above, whom they name Orru'nae and to whom they give the first fish of every crossing.