MONOGYNIA.

ONE FEMALE.

THIS first order is by far the most extensive of the whole. The following are a few of the genera which it contains: Sophora, Podalyria, Anagyris, Cercis, Bauhinia, Poinciana, Myroxylon, Parkinsonia, Cæsalpinia, Toluifera, Cassia, Guilandina, Dictamnus, Adenanthera, Hæmatoxylum, Melia, Swietenia, Guajacum, Ruta, Zygophyllum, Quassia, Limonia, Monotropa, Clethra, Pyrola, Ledum, Dionæa, Melastoma, Andromeda, Rhododendron, Kalmia, Rhodora, Epigæa, Gaultheria, Arbutus, Styrax, Inocarpus, Cassuvium, Samyda, Copaifera, and others*.

DIGYNIA.

TWO FEMALES.

THE second order contains the following genera: viz. Scleranthus, Trianthema, Chrysosplenium, Hydrangea, Saxifraga, Tiarella, Mitella, Cunonia, Saponaria, Dianthus, &c.

* The genera Rhododendron, Kalmia, Rhodora, and Ledum are the Decandrous plants of Jussieu's order Rhododendra. Azalea and Itea (Pentandrous plants), Menziesia (of the class Octandria), and Befaria (of the class Dodecandria) belong to the same fine order.

TRIGYNIA.

THREE FEMALES.

CUCUBALUS, Silene, Stellaria, Arenaria, Malpighia, Banisteria, and others, belong to this order.

PENTAGYNIA.

FIVE FEMALES.

AVERRHOA, Spondias, Cotyledon, Sedum, Penthorum, Bergia, Oxalis, Agrostemma, Lychnis, Cerastium, and Spergula, belong to this order. Some species of Oxalis belong to the xvith class. One species of Lychnis (Lychnis dioica) belongs to the xx11d class. Lychnis alpina and L. quadridentata have often only four styles.

DECAGYNIA.

TEN FEMALES.

THIS is the most inconsiderable order of the whole. It contains the genera Neurada and Phytolacca. The latter is a very irregular genus. The species which

causes the genus to be arranged in the present order is the P. decandra, or Common Poke. A second species belongs to the VIIIth class; a third to the x11th, and a fourth to the xxiid class.

CHARACTER.

Ar the very head of this great class, we find So. phora, Anagyris, and some other genera, which belong to Linnæus's thirty-second order, Papilionacea, of which I shall make more particular mention, when treating of the plants of the xvi1th class. Cercis, Bauhinia, Hymenæa, Poinciana, Myroxylon, Parkinsonia, Casalpinia, Cassia, Guilandina, Adenanthera, Hæmatoxylum, and some others, belong to the thirty-third order, Lomentacea*, so called because several of the genera which it embraces furnish fine tinctures that are used in dying. Such are different species of Casalpinia, or Brasiletto; the Guilandina Moringa, the wood of which dies a fine blue colour; Hæmatoxylum Campechianum, called Logwood, or Campeachy-wood, &c. Melia, Swietenia, Malpighia, Banisteria, together with Esculus, and Tropæolum, and some other genera, which have already been mentioned in treating of preceding classes, belong to the twenty-third of Linnæus's natural orders, the order Tribilatat. Guajacum, Tribulus, Fagonia, Zy. gophyllum, Quassia, Dionæa, Oxalis, Averrhoa, and others, belong to the order Gruinales, which will be

*Lomentacea, from lomentum, a colour used by painters.

+ Tribilatæ, from tres, three, and hilum, the eye, or external scar of the seed already mentioned. Several of the vegetables of this order have three seeds, which are distinctly marked with an external cicatrix, or scar, where they are fastened within the fruit.

more particularly noticed when treating of the xvith class. Clethra, Pyrola, Ledum, Andromeda, Rhododendron, Kalmia, Epigæa, Gaultheria, Arbutus, Styrax, together with Azalea, Vaccinium, Erica, and others, which are afterwards to be mentioned, constitute the order Bicornes. I have already made some mention of this order*.

LINNEUS asserts, that there is no poisonous plant in the order Bicornes, unless, perhaps, the genus, Ledumt. ALIQUANDO BONUS DORMITAT HOMERUS. Some of the Bicornes are very poisonous vegetables, such are Kalmia latifolia and angustifolia, some species of Azalea, Andromeda, &c. Epigæa repens is said to be poisonous to sheep. Gaultheria is not an inert plant. I can say nothing certain concerning Clethra and Rhodora. I shall have occasion to speak of the properties of other Bicornes, when treating of the sexual classes to which they belong. From several of the plants of this order, bees obtain an abundance of honey, which, in some species, is endued with a noxious quality‡. Linnæus is, certainly, incorrect, when he asserts, that Kalmia is the only genus among the Bicornes, that is furnished with nectaries. Gaultheria procumbens, not to mention others, has these parts.

Hydrangea, Chrysospleniun, Saxifraga, Tiarella, Mitella, Cotyledon, Sedum, Penthorum, Bergia, together with Heuchera, formerly mentioned, and several

* See page 36.

"Vix quicquam Olidi continet ulla totius ordinis, excepto Ledo, nec ulla vene"nata est, nisi idem forte Ledum, quod tamen incertum adhuc est." Prælectiones, &c. p. 343.

See Part I. p. 152, 153.

others, which will be noticed in their proper places, be long to Linnæus's thirteenth natural order, Succulenta*, or Succulent Plants. It must not, however, be sup posed, that all the plants of this order are succulent, or especially juicy. Heuchera is far from being succulent. The same remark may be extended to Nymphæa, Sarracenia, and others. Several of Linnæus's Succulenta, belong to Mr. De Jussieu's order Saxifragæ.

THE class Decandria contains a beautiful tribe of vegetables, which constitute Linnæus's twenty-second natural order, Caryophyllei, formerly mentionedt. This is a pretty extensive tribe of plants. Beside the Triandrous and Tetrandrous genera which it contains, the following Decandrous genera belong to its viz. Gypsophila, Saponaria, Dianthus, Arenaria, Stellaria, Cucubalus, Silene, Spergula, Cerastium, Agrostemma, Lychnis, and others. Most of these genera belong to Jussieu's order Caryophyllea.

In a medical point of view, the class Decandria is by no means unimportant. That valuable medicine, the gum-resin Guaiacum, is the produce of the Guajacum officinale. The Toluifera Balsamum furnishes us with the Balsam of Tolu, the Copaifera officinalis with the Balsam of Capaevi, and the Myroxylon peruiferum with the balsam of Peru. These four vegetables are natives of America, but are not known to be indigenous within the limits of the United-States. The Senna of the shops is the produce of the Cassia Senna. The leaves of some of the American species may be substituted for this. The bark of Swietenia febrifuga, of Roxburgh, has been found an excellent substitute for the * Succulenta from succus, juice.

+ See page 12.