A cloud variety, the elements of which are arranged in straight parallel bands. Owing to the effect of perspective, these bands seem to converge toward a point on the horizon, or, when the bands cross the entire sky, toward two opposite points (radiation points, V points, vanishing points, radiant points). This variety occurs in the genera cirrus, altocumulus, altostratus, and stratocumulus, and may modify many of the species, but principally stratiformis. See cloud classification, cloud streets.