XII. Icosandria. Stamens twenty, or more, inserted into, or growing out of the calyx. This mode of insertion al ways indicates an eatable and wholesome fruit.
1. Monogynia. Myrtus, Amygdalus, Prunus 2. Pentagynia. According toDr Smith, should comprise also the Digynia and Trigynia of Linnzeus, as they all vary one into the other. Pyrus, Mespilus, Spinzea, and Mesambrianthemum.
3. Polygynia. Rosa, and its beautiful natural order, including Rubus, Fragaria, &c.
XIII. Polyandria. Stamens numerous, Xiii. Polyandria. Stamens numerous, inserted into the receptacle. This class is very distinct in character and qualities from the last. Its plants are often poi sonous.
1. Monogynia. A fine order. Cappa ris, Papaver,Nymphxa, Cistus.
2: Pentagynia. Dr. Smith recommends, in his " Introduction to Botany," the same plan in this class as in the preceding, of uniting Digynia,Trigynia,Tetragynia, and Hexagynia of Linnzeus, under Pentagy nia, because, as they stand now in his works, natural genera, as well as the spe cies of one genus, are often separated, and several plants vary from one Linraean order to another. Examples are, Pxonia, Delphinium, Aquilegia, Nigella, Stratio tes. Some Nigell2e have ten styles.
3. Polygynia. Dillenia, Magnolia, Ane mone. Clematis, Ranunculus, &c.
XIV. Didynanda. Stamens two long' and two shor .
This class therefore is distinithished from the 4th by the proportion of its fila !Dents, a circumstance which is only an index to other characters in the flower, for there is a correspondent irregularity in the form of the corolla. The class in question is almost perfectly a natural one, containing the Labiate, Ringens, or Per sonate flowers in general. The orders are as natural as the class, being only two, and founded on the structure of the fruit.
1. Gymnospermia. Seeds naked in the bottom of the calyx, almost always four. The plants are aromatic and wholesome. Some of the principal genera are, Teucri um, Mentha, Lavandula, Lamium, Thy mus, and Melitis.
2. Angiospermia. Seeds inclosed in a seed-vessel, and generally very numerous. The plants of this order are handsome, but foetid and poisonous, quite distinct in nature from those of the former, and more akin to the Pentandria Monogynia. The genera Bignonia and Antirrhinum sometimes vary, with five stamens and re gular flowers. Interesting genera of this order are, Pedicularis, Chelone, Antirrhi num, Linnaa, Orobanche, and Acanthus.
XV. Tetradynamia. Stamens four long and two short. A natural class, compris ing the cruciform flowers, except Cleome, which is thought to have been erroneous ly placed here. The orders are two, per fectly natural.
1. Siliculosa. Fruit a roundish pod or pouch, Myagrum, Draba, Lunaria, Aly sum, Coch]earia, Tblaspi.
2. Siliquosa. Fruit a very long pod, Dentaria, Cardamine, Cheiranthus, Bras sica, Sinapis.
XVI. Monadelphia. Stamens united by their filaments into one tube. This is the first class in which the connection of those parts is taken into consideration. Num ber therefore being here of secondary importance, serves to discriminate the orders.
1. Triandria. Sisyrinchium, Ferraria, Tamarindus, Aphyteia.
2. Pentandria. Erodium, Hermannia.
3. Heptandria. Pelargonium only, se parated from Geranium by L'Herritier, an eminent French botanist.
4. Octandria. Aitonia, named by the younger Linnaeus after the late Mr. Aiton ,of Kew garden.
5. Decandria. Geranium.
6. Endecandria. Brownea only.
7. Dodecandria. Stamens generally fif teen. Pterospermum, Pentapetes, &c.
8. Polyandria. The finest order of the whole, contains Malva, Sida, Althxa, La .vatera, Gossypium, Hibiscus, Camellia, and others ; most mucilaginous emollient plants.
XVII. Diadelphia. Stamens united by Xvii. Diadelphia. Stamens united by their filaments into two parcels, both sometimes cohering at the base. Flowers almost universally papilionaceous.
1. Pentandria. Monnieria only.
2. Hexandria. Snraca, Fumaria.
3. Octandria. Polygala.
4. Decandria. The largest and most natural order, the sections of which re. quire to be studied with care.
* Stamens all united. These plants are strictly monadelphous, and it is only on account of their close affinity to the rest of the order, that Linnaeus took the liber ty of placing them here. Some of them, indeed, as Lupinus and Ulex, have the tenth stamen unlike the rest, though unit ed with them below. No confusion arises in practice from this seeming tion of the character of the class, because the habit of these flowers is so clear and distinct from all others. If; however, a papilionaceous plant has its ten stamens all separate and unconnected, it is neces sarily to be referred to the tenth class.