The genus Malope closely resembles the Mallow; except that the petals are not wedge-shaped, and that it has a still larger calyx, the long sepals of which shroud the capsule as the involucre of the filbert does the nut. The involucrum is composed of three broad, heart-shaped leaflets, which remain on till the seed is ripe. The petals are also not so even along the margin; and the carpels are so disposed as to form a cone-shaped capsule, instead of a flat one.
The genus Lavatera has the leaflets of the involucre joined to the middle, so as to form a kind of three-cornered saucer below the capsule; and the capsule itself is completely covered with a part of the receptacle, which is dilated, and curved down over it. Lastly, the genus Althæa, the Marsh Mallow, has the involucrum cleft into six or nine divisions, and the carpels united into a globular capsule. The Hollyhock (_A. rosea_) belongs to this genus. Many other genera might be mentioned, but these will suffice to give my readers a general idea of the order, and of the points of difference which distinguish one genus from another. Among the exotic plants belonging to the order is the cotton tree (_Gossypium herbaceum_), the cotton being the woolly matter which envelops the seeds in the capsule. All the Malvaceæ abound in mucilage, and they all have woody fibre in their stems.
ORDER XXIX.--BOMBACEÆ.--THE SILK COTTON TREE TRIBE.
This order is closely allied to Malvaceæ, and it differs principally in the tube formed by the stamens being divided into five bundles near the top. It includes the Baobab, or Monkey-bread (_Adansonia digitata_), said to be the largest tree in the world; the Screw tree (_Helicteres Isora_), so named from its curiously-twisted fruit; _Carolinia princeps_; the Silk Cotton tree (_Bombax Ceiba_); and the Hand-plant (_Cheirostemon platanoides_),--this is the Hand-plant so named from the lobes of its leaves resembling fingers,--all stove plants in Britain.
ORDER XXX.--BYTTNERIACEÆ.--THE BYTTNERIA TRIBE.
This order is divided into five sections, which some botanists make distinct orders. It is very nearly allied to Malvaceæ, but the anthers are two-celled. The principal genus in the first section (_Sterculieæ_) is Sterculia, which has several carpels distinct and arranged like a star: the species are trees with large handsome leaves which are articulated at the base, and axillary panicles or racemes of flowers. The second section (_Byttnerieæ_) contains among other plants _Theobroma Cacao_, from the fruit and seeds of which Cocoa and Chocolate are prepared. The third section (_Lasiopetaleæ_) is well known in England, by the pretty Australian shrubs included in the genera Thomasia and Lasiopetalum, the leaves of which have their under surface downy, and generally brown. The fourth section (_Hermannieæ_), and the sixth (_Wallichieæ_), contain no plant common in English gardens; and the fifth (_Dombeyaceæ_) is best known by _Astrapæa Wallichii_. The qualities of all the plants in this order are mucilaginous.