Stroma of iris
The stroma of the iris consists of fibers and cells.
The former are made up of delicate bundles of fibrous tissue; a few fibers at the circumference of the iris have a circular direction; but the majority radiate toward the pupil, forming by their interlacement, delicate meshes, in which the vessels and nerves are contained.
Interspersed between the bundles of connective tissue are numerous branched cells with fine processes.
In dark eyes many of them contain pigment granules, but in blue eyes and the eyes of albinos they are unpigmented.