Leaf anatomy. The leaf lamina dorsiventral. Hydathodes present (sometimes), or absent. Stomata paracytic. Lamina with secretory cavities (commonly), or without secretory cavities. Secretory cavities variously with brown, red, or sometimes transparent and crystalline contents; variously interpreted as schizogenous, or lysigenous. The mesophyll containing crystals. The crystals mostly solitary-prismatic. Minor leaf veins without phloem transfer cells (Oxalis).