Centaurea Americana. - American Centaurea. - A hand-some hardy annual, discovered by Nuttall, on the alluvial soil of the Arkansas and Red rivers, two or three feet high, with large purplish-pink flowers in August. It is of easy culture, and should be sown early in April.

Centaurea cyanus, - Blue Bottle, - is a common weed, in cornfields, on gravelly soils, throughout Europe, and also a popular border annual. The flower, originally blue, in gardens present varieties with white, pink, purple and parti-colored rays. The time of sowing early in April.

Centaurea moschata purpurea - var. alba. - Purple Sweet Sultan, White do. - Handsome border annuals, of easy culture, natives of Persia, two feet high, with fragrant flowers from July to September. Sow in April.

Centaurea suaveolens. - Yellow Sweet Sultan. - A hand-some annual from the Levant, one and a half foot high, with lively, rich yellow flowers from July to September. Sow first of May.

Centaurea benedicta. - Blessed Thistle. - A hardy annual from Spain, two feet high, with yellow flowers from July to September. Sow last of April.