The Graminaceæ are very numerous, but the general structure is virtually the same, whether it be a simple herbaceous grass, a sugar cane, or a bamboo. The stem of the grasses is jointed, and furnished with long lanceolate leaves, springing alternately to the right and left of each successive joint, and the parts of the stem between the joints are embraced and nearly surrounded, as by a sheath, with the expanded bases of the leaves; for, in this class of plants, one growth always springs from the interior of that which precedes it. In youth the stems of the grasses are solid, and the bundles of woody tissue which surround the pith are parallel to one another and to the axis of the stem; but, at the joints, they are turned aside and are condensed into a node or joint, where they enter into a new arrangement, and pass into the lanceolate leaf, to form its longitudinal ribs. The compression of the fibro-vascular tissue is so great as to form a septum across the interior of the stem as the node. This is the case in all the grasses; for the pith, which is of moist green cellular tissue when they are young, soon disappears, so that a full grown grass is a hollow stem articulated at intervals by solid joints, from whence the long narrow leaves spring alternately, and as the bases of the leaves are continuous with the stem, they do not fall off when they wither. In the majority of cases, the inflorescence of the Graminaceæ consists of a pistil and three anthers; but in the Anthoxanthum odoratum, or sweet-scented vernal grass, and some others, there are but two anthers, while some few species have more than three. In general, the flowers are hermaphrodite; but in certain genera they are monœcious, as in Zea and Zizania; and in others they are polygamous, as in Andropogon and Sorghum. The grasses are, for the most part, low and herbaceous; but the Arundo Donax of Southern Europe, and the sugar cane and bamboo of the tropics are lofty strong-growing plants, the latter reaching as much as 50 or 60 feet in height. The stems and leaves of the grass family are strengthened by silex; many of them are so entirely coated with it, that their leaves are as sharp as the edge of a knife. It gives hardness to the beards of wheat and barley, and is often found in concrete masses, called tabasheer, in the joints of bamboos, which in the Indian jungles have been set on fire by the friction of their silicious coats during a gale of wind. As no solid matter can enter the roots of a plant, the silex must be absorbed in a state of solution; and, as it coats the surface, which is full of pores, the liquid is removed by perspiration, and the silex is consolidated. The whole of this family abounds in sugar, and its farinaceous products are too well known to require any notice.