BLUETS (Houstonia caerulea), a popular North American wild flower of the madder family (Rubiaceae), known also as in nocence, eyebright and quaker-ladies. It is native to grassy places and wet rocks from Nova Scotia to Wisconsin and south to Georgia and Missouri. This early spring favourite, which grows perennially in matted tufts, with smooth stems 3 in. to 7 in. high, is aptly described by Asa Gray as "a delicate little herb producing in spring a profusion of light blue flowers fading to white, with a yellowish eye." In the southern United States there are about 20 other species of Houstonia, some of which are known as bluets, as the thyme-leaved bluets (H. serpyllifolia), the least bluets (H. minima), the small bluets (H. patens), and the purple bluets or Venus' pride (H. purpurea) which grows 18 in. high. In Great Britain the corn bluebottle (Centaurea Cyanus) is sometimes called bluet.