Crow's eye plant

A model of perfect plant symmetry, the four-leaved true lover's knot, in Slovak and Czech known under a popular name crow's eye, inhabits moist shady places, especially in deciduous forests. The plant catches the eye with its delicate, unusually symmetrical yellow-green flowers, which reign over a quartet of broad leaves placed at the top of the stem.

Paris quadrifolia, the herb-paris or true lover's knot, is a species of flowering plant in the family Melanthiaceae. It occurs in temperate and cool areas throughout Eurasia, from Spain to Yakutia, and from Iceland to Mongolia. The plant flowers during the months of June and July. It has a solitary flower with four narrow greenish filiform (threadlike) petals, four green petaloid sepals, eight golden yellow stamens, and a round purple to red ovary. The flower is borne above a single whorl of four leaves. Each plant produces at most one blueberry-like berry, which is poisonous, as are other plant tissues.

Poisonings are rare because the plant's solitary berry has a repulsive taste that makes it difficult to mistake for a bilberry. In such cases, narrow pupils, diarrhea, irritation of the kidneys are typical. The main poisonous substances of the plant are the saponins paridin and paristyphnine - violent poisons that are poorly absorbed in the digestive system.

The medical uses of true lover's knot are already mentioned by the Italian botanist Matthioli in his commentaries on De Materia Medica, a 5-volume work on Dioscorides, a treatise on plants and the medicines that can be obtained from them. The plant is also mentioned in the work of the English botanist and healer John Gerard as an antidote for arsenic and mercury poisoning. This plant has also been used in the past as an anti-inflammatory (e.g. for inflamed wounds) and for headaches. It is now part of many homeopathic remedies.