This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Erect annuals with alternate finely dissected compound leaves. Flowers solitary, terminal, yellow, blue, or white, surrounded by a finely divided leafy involucre in some species Sepals 5, regular, petaloid. Petals small, bifid. Carpels 3 to 10, more or less combined. Natives of the Mediterranean region. The name is said to be derived from niger, black,- in allusion to the colour of the seeds.
1. N. damascena. Devil-in-a-Bush, Love-in-a-Mist. - About 2 feet high, with finely-cut leaves and pale blue flowers encircled by a leafy involucre.
2. N. Hispanica. - With larger white, lilac, or dark purple flowers, and no involucre. Both flower in Summer.