oxalic

Euphrasia, or eyebright, is a genus of about 450 species of herbaceous flowering plants in the family Orobanchaceae (formerly included in the Scrophulariaceae), with a cosmopolitan distribution. They are semi-parasitic on grasses and other plants. The common name refers to the plant's use in treating eye infections.

Many species are found in alpine or sub-alpine meadows where snow is common. Flowers usually are borne terminally, are zygomorphic, and have a lower petal shaped like a lip. The most ...