Cynoglossum officinale
Cynoglossum officinale (houndstongue, houndstooth, dog's tongue, gypsy flower, and rats and mice due to its smell) is a herbaceous plant of the family Boraginaceae, found in most parts of Europe, and also North America where it was accidentally introduced.
Growth
It can be either annual or biennial, with reddish-purple flowers blooming between May and September. It lives in wet places, waste land and hedges.
Folklore
The name houndstongue comes from the belief that it could ward off dog attacks if a leaf was worn in the shoe.
Herbalism
Herbalists use the plant as a treatment for piles, lung diseases and persistent coughs. Houndstongue ointment is said to cure baldness and be used for sores and ulcers. These uses are not supported by scientific evidence.
In 1725, houndstooth was presented in the family dictionary, Dictionaire oeconomique, as part of a cure for madness. In that book, madness was viewed as "a distemper, not only of the understanding, but also of the reason and memory, proceeding from a cold, which drys up everything it meets with that is humid in the brain." To cure madness, Dictionaire oeconomique noted: