Bicornes*, so called because in many of the plants of this order, the anthers have the appearance of two hornst. Mr. De Jussieu's order Erica comprehends the genera Erica, Vaccinium, and several of Linnæus's Decandrous vegetables, which are afterwards to be mentioned; and some genera belonging to neither Octandria nor Decandria. Gnidia, Dirca, Daphne, Passerina, and some others, form Linnæus's thirty-first order, Vepreculat. Paris belongs to the order Sarmentaceæ. Elatine, together with Hippuris, Proserpinaca, and several others, constitute Linnæus's fifteenth order, Inundatæ. These plants grow naturally in the water.

We know but little of the medical properties of the plants of this class. Their other properties are better investigated. The fruits of various species of Vaccinium, comprehending the Whortle-berries and Cranberries, are esculent and wholesome. To some constitutions, however, some of the Whortle-berries are disagreeable. The common American Cranberry (Vaccinium macrocarpon of Aiton) is an important vegetable, on account of its fine acid fruit. The buds of Tropæolum make a good pickle. Different species of Polygonum, particularly the Polygonum Fagopyrum (Buckwheat), and the Polygonum tataricum, furnish us with a very nutritious and agreeable article of diet. The first of these vegetables is much cultivated, and the last should be cultivated, in the United-States. The pulverized leaves of the Lawsonia inermis (which the Arabs call Henna, or Alhenna) are much used by the Egyptians, Persians, and other people of Africa and

* Bicornes, from bis, twice, and cornu, a horn.

+ Of this order, I shall tale further notice, in treating of the class Decandria. Vepreculæ, from vepres, a brier.

Asia, to die the nails of their hands and feet of a yellow colour. In Egypt, this practice appears to have been of a very ancient date. The flowers of the Lawsonia have that peculiar animal smell which I formerly hinted at*. The The gum Elemi of the shops is supposed to be the produce of the Amyris Elemifera, a native of Carolina. The Opobalsamum, or Balsam of Mecca, is ob tained from another species, the Amyris Opobalsamum. Different species of Daphne, particularly Daphne Mezereum and D. Gnidium, are important articles in the materia medica, and perhaps, too much neglected. Dirca is said to be used as a cathartict. The root of Paris quadrifolia is emetic, and it is thought may be substituted for ipecacuanha. Useful medical qualities are ascribed to Oenothera biennis: but of these qualities I can say nothing, from my own experience.

Of the genera which I have mentioned, the following are known to be natives of the United-States: viz. Epilobium, Gaura, Oenothera, Rhexia, Chlora, Vaccinium, Menziesia, Dirca, and Polygonum. Not a single species of Erica is to be met with in this great tract of country! But in place of "the blooming Hather," nature has liberally supplied our country with various species of Andromeda, Vaccinium, not to mention other genera, which are nearly allied to Erica. The Hudsonia ericoides (one of Jussieu's Erica) is extremely common in many parts of the United-States, and has greatly the facies, or aspect, of an Heath.

FOR an illustration of this class, see Plate xvI.

See Part I. p. 165.

+ See Collections for a Materia Medica, &. p. 31. See, also, p. 22.

CLASS IX.

ENNEANDRIA.

NINE MALES.

ENNEANDRIA* is the name of the ninth class. This class contains those hermaphrodite flowers which are furnished with nine stamens, or male organs, and is subdivided into three orders, viz. MONOGYNIA, TRIGYNIA, and HEXAGYNIA.

MONOGYNIA.

ONE FEMALE.

TINUS, Laurus, Anacardium, Panke, Volutella, Ginannia, and Cassyta belong to this order.

TRIGYNIA.

THREE FEMALES.

THIS order contains the important genus, Rheum, or Rhubarb, of which several species are now known to the botanists.

Enneandria, from evvex, nine.

HEXAGYNIA.

SIX FEMALES.

THE genus Butomus, or Flowering Rush, belongs to this order.

CHARACTER.

WITH respect to the genera which belong to the class Enneandria, they constitute different assemblages of vegetables, more or less natural. Laurus, Anacardium, Rheum, together with Callitriche, Blitum, Corispermum, Rumex, Polygonum, and several others, which have already been mentioned, as belonging to preceding classes; and, also, certain genera which are arranged in the succeeding classes, constitute Linnæus's twelfth order, Holoracea*, which I do not think entitled to the name of a natural order. The The genus Laurus gives name to an order in the system of Mr. De Jussieu. It is the fourth order of his sixth class. In the system of the same learned naturalist, there is an order entitled Polygonea, which embraces one of the genera of the class Enneandria; the genus Rheum. Butomus, together with Calamus, Juncus, Triglochin, and some others, belong to Linnæus's fifth order, Tripetaloidea↑.

* Holoracea, or Holeracea, more commonly written Oleraceæ, from olus, or bolus, a pot-herb. Several of the genera of this order are arranged by Jussieu in his order Atriplices.

+ From tres, three, and petalum, a petal; because several of the genera have three petals. See MONOECIA.

THE class Enneandria, though a very small class, contains a number of important vegetables. Different species of Laurus are highly important for medical or domestic purposes. Camphor is the produce of the Laurus Camphora, Cinnamon of the Laurus Cinnamomum, and Cassia of the Laurus Cassia. To the Laurus Benzoin, the people of the United-States have ascribed useful medical powers. The Laurus Sassafras, or Sassafras, it entitled to the attention of physicians. The leaves of the Laurus Borbonia are used as a spice, in some parts of the United-States. The Laurus nobilis, which the Greeks called Aaç, is the species which was dedicated to Apollo, and employed as a crown or garland for the heads of the Roman emperors, pontifs, and poets.

THE different species of Rhubarb are valuable cathartics, particularly the Rheum palmatum, or Palmated Rhubarb. I think it not improbable, that North-America possesses some native species of this genus. Be this as it may, the cultivation of Rhubarb ought to be attended to in the United-States.

THE United-States possess few plants of the class Enneandria. It is true, that several species of Laurus are natives of this great tract of country: but our species are by no means constantly furnished with nine stamens. Thus, Laurus Sassafras is sometimes found dioicous, and Laurus Borbonia belongs to Decandria.

FOR an illustration of the class Enneandria, see Plate XVI.