These plants are very nearly allied to the last, and they differ chiefly in having the segments of their corollas straight, in their stamens being united into a sort of crown, and in their pollen being found in masses of a waxy substance. The seeds are also each furnished with a tuft of fine long silky hair. The principal plants are _Periploca græca_, a hardy, climbing, shrub, with rich, dark, velvet-looking flowers, which are said to be poisonous to flies, and _Hoya carnosa_, a stove or greenhouse climber, with waxen-looking, clustered, odoriferous flowers, distilling honey; to these may be added Pergularia, a stove climber, remarkable for its fragrance, Physianthus, Gonolobus, Ceropegia, and Asclepias, all singular-looking climbing plants; and besides these, I may mention Stapelia, the species of which are dwarf plants, with their flowers hanging down below the pots in which they grow, and the odour of which is so like that of carrion, as to induce flesh-flies to lay their eggs upon them. ORDER CXXIX.—GENTIANEÆ.—THE GENTIAN TRIBE. The best known genera are Gentiana, (the Gentian), Lisianthus, and Menyanthes (the Buckbean). The flowers have a tubular calyx and corolla, the latter plaited in the tube, and with an equally-parted limb, which is generally five cleft; and an equal number of stamens with broad filaments, and arrow-shaped anthers. The seeds are numerous, and are usually in two follicles. The orders Spigeliaceæ, Loganiaceæ, and Menyanthaceæ, have been separated from Gentianeæ, and are adopted by some botanists. ORDER CXXX.—BIGNONIACEÆ. The most interesting genera are—Bignonia; from which Tecoma has been divided by some botanists, on account of a slight difference in the seed-pod; Jacaranda, said to produce the rosewood of commerce; Eccremocarpus, and Catalpa. All the plants included in this order have winged seeds, and generally very long horn-like seed-pods. The different species of Bignonia or Tecoma have trumpet-shaped flowers with a five-toothed calyx, and four stamens of unequal length, with the rudiments of a fifth. The capsule is very long and narrow, resembling a silique in shape, but broad on the outside, and the leaves are pinnate. _Eccremocarpus_, or _Calampelis scabra_, is a well-known climber, with orange-coloured, bag-like flowers, which are produced in secund racemes; large, roundish warted fruit, with winged seeds; and pinnate leaves, with tendrils. In Catalpa the corolla has a very short tube, and an unequal, five-lobed limb. There are five stamens (only two of which are fertile); and an exceeding long, cylindrical, silique-shaped seed-pod, which is sometimes two feet or more in length. The leaves of the Catalpa are heart-shaped. In Jacaranda, the capsule is above two feet long, and quite flat. _Crescentia cujète_, the calabash-tree, belongs to this order. ORDER CXXXI.—COBÆACEÆ.