The genus Polygala is well known from the very handsome greenhouse plants which it contains. The flowers at first sight appear to resemble those of the Sweet Pea, having two wings like a standard, and a sort of keel; their construction is, however, very curious, and so complicated, as to be very difficult either to describe or to understand. The calyx is said by modern botanists to consist of five sepals, three of which are green and two lilac, these last being the part that resembles the standard of the Sweet Pea. The corolla is also said to consist of five petals, two of which stand erect, and the other three grow together to form the keel. The latter have their upper part cut into a kind of crest, like that of the Mignonette. Below the crest, the united petals form a kind of hood, under which are arranged the eight stamens, four on each side. The stamens themselves are as remarkable as the other parts of the flower; the filaments grow together into a thin kind of leaf, and each anther has but one cell, and opens by a pore at the apex. The pistil is also very curiously formed, as the style and stigma have the appearance of a gaping monopetalous corolla. The fruit is a flat two-celled capsule, which, when ripe, opens by two lips, separating from each other, and showing a seed within each cell. Even the seeds are not like other seeds, for each has a large white protuberance at one end, called a corancula. ORDER XXIII. TREMANDREÆ. Slender New Holland shrubs, with the habit of Heaths, rarely met with in British gardens. ORDER XXIV. PITTOSPOREÆ.—THE PITTOSPORUM TRIBE.