viper's bugloss; a genus of the monogynia order, belonging to the pentandria clas of plants. There are seven species, three of which are natives of Britain. None of them have any remarkable property, except that the flowers of one species (the vulgare) are very grateful to bees. It is a native of many parts of Britain. The stem is rough with hairs and tubercles. The leaves are spear-shaped, and rough with hair. The flowers come out in lateral spikes. They are first red, afterwards blue; sometimes purple or white.—Cows and sheep are not fond of the plant; horses and goats refuse it.