lugo, Minuartia, Queria, Koenigia, Triplaris, and Proserpinaca

CHARACTER.

THIS is, in various respects, a natural class. The first order is less natural than the second. The genus Valeriana, or Valerian, is an irregular one, some of the species having only one, while others have three, and some four stamens. Iris, Crocus, Moræa, Antholyza, Gladiolus, Ixia, and some others, have considerable affinities to each other. They, together with Commelina, Tradescantia, Pontederia, &c. constitute Linnæus's sixth order, called Ensata; a name given to them, by the Swedish naturalist, on account of the form of their leaves, which is thought to resemble that of a sword*. This order likewise contains some grasses, such as Schoenus, Cyperus, &c. But the second order is almost entirely made up of plants of this family, many of which are highly important to mankind. The Sugar-cane is the Saccharum officinarum. The Avena, or Oat, the Secale, or Rye, the Triticum, or Wheat, the Hordeum, or Barley, not to mention others, are among the number of the most important vegetables with which we are acquainted. I have taken notice of some of the most essential characters of the grasses, in former parts this workt.

SEVERAL of the plants of the third order of this class, are arranged by Linnæus in his twenty-second natural order, the order Caryophyllei.

See Part 1. p. 34. n. 80.

+ See Part I. p. 24-26. and p. 118122.

In a medical point of view, the class Triandria is much less important to mankind than several of the other classes of the system. Nevertheless, this class contains some useful articles of the materia medica (properly so called), such as the Valeriana officinalis, or Valeri an; the Crocus sativus, or Saffron; different species of Iris, or Flag; the "fever-cooling" Tamarind*, &c.

MANY of the genera of this class are natives of the United-States.

FOR an illustration of the class Triandria, see Plate X.

CLASS IV.

TETRANDRIA.

FOUR MALES.

THE fourth class is denominated TETRANDRIAT. This class contains hermaphrodite flowers, which are furnished with four stamens, or male organs, which are all of an uniform length. By this latter circumstance, the plants of the class Tetrandria are distinguished from those of the XIVth class, or Didynamia: for this last class comprehends plants that have also four stamens,

• Thomson.

+ From Toσages, four.

two of which are long, and two short. See DIDYNA

MIA.

THE class Tetrandria is subdivided into three or ders, viz. MONOGYNIA, DIGYNIA, and TETRAGYNIA.

MONOGYNIA.

ONE FEMALE.

THIS order contains the following genera, viz. Protea, Globularia, Hydrophylax, Cephalanthus, Dipsacus, Scabiosa, Knautia, Allionia, Aquartia, Callicarpa, Scoparia, Bartonia*, Centunculus, Plantago, Polypremum, Buddleia, Exacum, Penaea, Blaeria, Pavetta, Ixora, Petesia, Catesbaea, Mitchella, Hedyotis, Oldenlandia, Mannettia, Sanguisorba, Houstonia, Scabrita, Rubia, Galium, Asperula, Sherardia, Spermacoce, Knoxia, Diodia, Crucianella, Siphonanthus, Epimedium, Rhacoma, Ptelea, Samara, Fagara, Ammannia, Banksia, Hartogia, Trapa, Cissus, Cornus, Ludvigia, Santalum, Rivina, Camphorosma, Alchemilla, Dorstenia, Cometes, Sirium, Isnardia, and Elæagnus.

***
**

To this order belong various species of plants, the genera of which are placed by Linnæus, in other classes

• Bartonia of Professor Willdenow.

of his system. I shall mention the following, viz. Valeriana sibirica, Swertia corniculata, S. dichotoma, some species of Gentian and Euonymus, Coffea occi. dentalis, Peplis tetrandra, Cardamine hirsuta, Corchorus Coreta, Convallaria bifolia, Thesium alpinum, Melastoma tetrandrum, Hillia tetrandra, &c. &c.

DIGYNIA.

TWO FEMALES.

THIS order contains the following genera, viz. Buffonia, Hypecoum, Hamamelis, Cuscuta, Aphanes, Cruzita, and Gomozia.

TETRAGYNIA.

FOUR FEMALES.

THIS order contains the following genera, viz. Ilex, Coldenia, Sagina, Tillæa, Myginda, Potamogeton, and Ruppia.

CHARACTER.

THE class Tetrandria has some claim to the cha. racter of a natural class of plants. Several of the genera of the first order, such as Protea, Banksia, Globularia, Cephalanthus, Dipsacus, Scabiosa, &c. &c. form a part of Linnæus's forty-eighth order, the order Aggregate.

Protea, Banksia, Roupala, Brabeium, and Embothrium, constitute the order Protea in the learned system of Mr. De Jussieu. This is a very magnificent order of vege tables. Ixora, Hedyotis, Houstonia, Rubia, Galium, Asperula, Sherardia, Spermacoce, Knoxia, Diodia, Crucianella, Cornus, &c, from a part of Linnæus's forty-seventh natural order, Stellata. All these genera, together with many others which Linnæus has introduced as well into the fourth as into other classes of his sexual system, constitute an extensive order of vegetables, to which Mr. De Jussieu has given the name of Rubiacea.

THE class Tetrandria contains several plants that are entitled to the attention of physicians. The Rubia tinctorum, or common Madder, has been recommended in different diseases, particularly as an emmenagogue. Several species of Cornus, especially the Cornus florida, or Dogwood, and the Cornus sericea, called Redwillow, and Red-rod, have been found useful substitutes to the Peruvian bark, in the treatment of intermittent and other fevers. The bark is used. These are NorthAmerican plants. The Dorstenia Contrayerva is the Contrayerva of the shops; an article, I think, of no great value: Some species of Ilex, or Holly, deserve to be farther investigated, particularly the Ilex vomitoria of Aiton. This, which is the Yaupon, Yopon, Cusseena, or Cassena, of our Southern Indians, is a very powerful diuretic. It is also one of the most interesting vegetable articles in the history of the American Indians. If there were no other reasons to believe, that the Americans, and certain Asiatics, particularly the Japanese and Chinese, were the children of a common stock, or family, we should almost be led to adopt this opinion from an attention to the tradition of the Carolina-Indi

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