Flowers: terminal; solitary. Calyx: large, with five linear lobes alternating with and exceeding the corolla. Corolla: of five rounded petals. Stamens: ten. Pistil: one; styles, five. Leaves: opposite; linear-lanceolate; pale green; hairy. Stem: stout, erect; much branched; four-angled.
The generic name lychnis, which was formerly applied to this plant and which means a lamp or light, expressed well the effect of the corn-cockle in our grain fields. It illuminates them with a blaze of crimson light and causes the traveller to exclaim, the fields here are as beautiful as they are in England.
But the farmer and the artistic eye seem to be always at variance. He understands the seriousness of things and regards the plant as an impudent foreigner that has secured first a footing, then a home, and finally a kingdom in his corn fields. The cockle is also alarmingly clever. It mixes its black seeds with those of the grain and so increases its dominion every year. They draw tears of lamentation from the sturdy miller who prides himself on his flour's purity and whiteness.
The plant also contains a poisonous ingredient called saponin which is freely soluble in water and when inhaled produces violent sneezing. It is known that a small quantity of bread that contains these seeds if eaten regularly will produce a peculiar chronic disease.