The cause of squamous blepharitis, though uncertain at present, is concerned with the functional hypersecretion of the tarsal glands, for, in the affected part of the lid-margins, oval furfuraceous bacillus can be often found, which may decompose the lipid substances into an irritable fatty acid. Ametropia, anthenopia, malnutrition, and a long-time use of unqualified cosmetics may be the predisposing cause of the disease. Ulcerative blepharitis, an acute or subacute suppurative inflammation of the ciliary follicles and their accessory glands, is usually caused by the infection of the golden staphylococci or transformed from squamous blepharitis having been infected.  Angulary blepharitis is a chronic inflammation mainly occurring in the canthi, and it is usually caused by the inflection of Morax-Axenfeld bacillus or is associated with the deficiency of riboflavin.