Centaurea calcitrapa, Centaurea chamaerhaponticum, Centaurea pygmaea.

Centaurea calcitrapa Linn. Compositae. Caltrops. Star Thistle.

Europe, north Africa and temperate Asia. The young stems and leaves, according to Forskal, are eaten raw in Egypt.

Centaurea chamaerhaponticum Ball.

Mediterranean coasts. In Algeria, according to Desfontaenes, the root is edible and not unpleasant to the taste.

Centaurea pygmaea Benth. & Hook. f.

Mediterranean countries. The roots have an agreeable flavor and are eaten by the Arabs in some parts of Africa.

Sturtevant's Edible Plants of the World, 1919, was edited by U. P. Hedrick.