24. Buckwheat is sometimes included among cereals because it is cultivated for its grain. As will be seen, however, from Fig. 22 this plant differs very much from the other cereals. It is a native of northern Asia where doubtless it has been cultivated for a long time; yet its introduction into other regions was comparatively recent. Like rye its chief merit is that it will yield a profitable crop on very poor soil. The flour made from it, however, is correspondingly poor in nutritive value. It is usually mixed with other sorts of flour to which it imparts an, agreeable flavor.

Fig. 22. Buckwheat (Fagopyruni esculentum, Buckwheat Family, Polygonaceoe).

Fig. 22.-Buckwheat (Fagopyruni esculentum, Buckwheat Family, Polygonaceoe). A, upper part of plant, showing leaves and flower-clusters; natural size. B, a flower enlarged, showing the following parts:-in the center a single pistil on the ovary of which are borne three styles ending in rounded stigmas; around the pistil eight stamens in two rows, the inner row of three; between the rows of stamens at their bases, eight small protuberances (nectar-glands) which secrete a sweet liquid (nectar) from which bees make honey; outside of the other parts of the flower come a circle of five more or less leaf-like organs-the sepals- together constituting the "flower-cup" or calyx which in this case is white or whitish. C, the same showing the arrangement of its parts as they appear when the flower is halved vertically. D, stamens. E, the pistil enlarged. H, fruit, enlarged. E, the same cut lengthwise. J, the same, cut across, showing the flat curved embryo or rudimentary plantlet surrounded by seed food. G, embryo removed from the seed and viewed from the side. (Baillon.)-The plant grows luxuriantly in fields to a height of 0.5-1. m. It is smooth throughout. Bees which come for nectar transfer the pollen from flower to flower and so enable the plant to set good seed.