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(eyebright), a genus of plants of the family Scrophulariaceae. The plants are annual and, less commonly, perennial hemiparasitic grasses. The leaves are opposite, sessile, and serrate or toothed. The small flowers have two-lipped corollas and are white, lilac, or purple. They are borne singly in the axils of the bracts, forming long spicate inflorescences. The fruit is a capsule.
There are approximately 200 species of eyebright. They are commonly polymorphic. The plants are distributed throughout the northern hemisphere, as well as in the mountains of the Malay Archipelago, in Australia, and in the temperate zone of South America. About 60 species are found throughout the USSR, growing in meadows, pastures, open fields, and thickets. The most common species is E. stricta, which, like many other species of Euphrasia, parasitizes grains. It sometimes reduces meadow harvests significantly.