From a crustose lichen belonging to the genus Caloplaca, a new trichloro-depsidone named caloploicin (Ia) has been isolated in addition to a dichloro-depsidone : vicanicin (IIa) and four known anthraquinone derivatives : parietin (III), fallacinol (IV), fallacinal (V), and emodin (VI), and the structures Ia and IIa have been elucidated on the bases of chemical and physicochemical evidences. It has been suggested that caloploicin would be a common constituent of some species of the genus Caloplaca. As for vicanicin, it has been demonstrated that the accumulated evidences are in good accord with the revised structure (IIa) rather than the previously proposed one [E].