It is lined by an epithelium which here consists of a single layer of columnar 17 or cuboidal cells with large nuclei.
Granite having a cuboidal and rude columnar structure, Land's End, Cornwall.
cuboid cu·boid (kyōō'boid')
Having the approximate shape of a cube. n.
A tarsal bone on the outer side of the foot, articulating in front with the calcaneus and lateral cuneiform, and behind with the fourth and fifth metatarsal bones.