(From joyful; because it exhilarates the spirits,) ocularia, eye bright; euphrasia officinalis Lin. Sp. Pi. 841. It is a herb with small, oval, serrated leaves, set in pairs without pedicles: the flowers appear on the top of the stalks; are white outwardly, but inwardly streaked with purple and yellow. It is annual, grows wild in uncultivated grounds, and flowers from July to September.

It is a very mild astringent, and hath been much extolled in disorders of the eyes. Both spirit and water extract its virtues. An infusion, and sometimes the powder in the manner of snuff, are taken in cases of weak sight. The following preparation, called helidaei, hath been held in great repute. euphrasia ij. macis 3ss. m. f. pulv. cap. 3i. ad 3 iij. Euphrasia is an ingredient in the British herb tobacco.