Cirrus castellanus (Ci cas) - CCH 1953

Fairly dense Cirrus in the form of small rounded and fibrous turrets or masses rising from a common base, and sometimes having a crenellated (castle battlement) appearance. The apparent width of the turret like protuberances may be smaller or greater than 1° when observed at an angle of more than 30° above the horizon; distinct to Cirrocumulus castellanus where the width is less than 1°.