​PENNYWORT, the Marsh, or Hydrocotyle vulgaris, L. an indigenous perennial plant, growing in marshy or inundated grounds; and flowering in the months of May and June.—This herb is supposed to occasion the rot in sheep: it certainly contains an acrid, poisonous juice, which, according to Bechstein, produces in the animals feeding on it, inflammations, bloody urine, and other mortal symptoms. Hence, every industrious farmer will endeavour to eradicate the pennywort from his meadows.