ePub 版

ral order called Multisilique, or many pods, there being many pod-form capsules to each flower.

In the same order we find the Peony (Pæonia), a showy flower which, when in its native state, has a 5 leaved calyx, a corolla with 5 petals, and 2 or 3 germs, each crowned by a stigma; the capsules the same in number as the

germs ;

each contains several seeds; this flower is particularly remarkable for its change by cultivation.

Polygynia. The Thirteenth Order is divided into two sections. 1st, flowers with no calyx or perianth. 2d, with a perianth. In the first sec. tion we find several interesting native plants. The Clematis or Virgin's bower, is a beautiful climbing plant, which supports itself by winding its petioles, or leaf-bearing stems, around other plants: the flowers are white and clustered in corymbs; the seed has a long silk-like fringe, which gives it a fine appear. ance after the blossoms have faded. This plant contains many species, and is cultivated both in this country and in Europe.

At fig. 116, a, is a flower of the Clematis; b represents its receptacle with numerous styles proceeding from it, and the petal and stamens separated, shewing that the former were in. serted upon the receptacle.

The ANEMONE is a beautiful native flower; by cultivation its petals multiply, as in the Rose.

The RANUNCULUS contains many species; it belongs to the same natural family as the Anemone ; but as you will find these plants very common, and are now able to analyze them, we will not at this time devote attention to them.

The HELLEBORE (Helleborus) is an exotic much spoken of by classical writers. Hippocrates, one of the most ancient phy. sicians, remarks upon its qualities: it grew about Mount Olym. pus, and was regarded as a very poisonous plant.

The Magnolia* and Tulip tree are among the most splendid trees of North America; they are said also to be common to China. The Magnolia grandiflora extends from South Caro. lina to the isthmus of Darien. In some cases these trees rise to the height of 90 feet before sending off any considerable branches; the spreading top is then clothed with deep green, oblong, oval leaves, like a laurel; these are at most seasons enlivened by large and fragrant white flowers.

The class Polyandria, though not important for its fruits, contains some valuable medicinal plants, besides opium and tea, which we have noticed.

* Named in honour of Magnol, a distinguished botanist.

Natural order Multisilique-Peony-Order Polygynia-Clematis-Anemone -Ranunculus-Hellebore-Magnolia.



The two classes which are to afford subjects for our present observations, are founded upon the number and relative length of the stamens.

In distinguishing their orders, the number of styles is not re. garded, but new circumstances of distinction are introduced, viz. the seeds: being enclosed in a capsule; or destitute of any such covering; and the comparative length of pods.

Class Didynamia.
Fig. 117.

This class has flowers with four sta. mens, two of which are longer than the other two; plants of this class are in general easily distinguished; the stamens stand in pairs; the outer pair being longer, the inner pair shorter, and converging

The class contains two orders, Gymd nospermia (naked seeds), and Angio

spermia (seeds covered).


Gymnospermia. In the 1st order, which contains plants with four naked seeds, the flowers grow in whorls or rings, having a square or angled stem, and leaves opposite. The corollas are labiate, having divisions resembling lips, and they are also called ringent, or gaping, because the lips appear to be open. The calyx is either

in five equal parts, or consists of two lips. At Fig. 117, a, is a flower of the genus Teucrium (german. der); the corolla is ringent; the upper lip is two-cleft; the lower lip is three-cleft; the stamens and pistils are incurved ; the stamens are exsert through the cleavage on the upper side ; b, shews the pistil with its four uncovered or gymnospermous seeds.

The plants of this order are mostly aromatic; very few are poisonous. We find here the Mint, Lavender, Penny-royal, Balm, and others of a similar nature. They are included un. der the natural family Labiata. For more particular remarks

Classes 13th and 14th, on what founded—Their orders-Class DidynamiaOrder Gymnospermia.

[ocr errors]

upon these plants, you can consult remarks on the Labiate flowers.

Angiospermia. The 2d order contains those plants which have their seed covered, or in a capsule ; the seeds are numerous. Plants of this order appear to have an affinity with some families of the class Pentandria. Many have, in addition to the four stamens, a fifth filament, which appears to be the rudiment of another stamen ; sometimes the irregular corolla varies into a regular form with five divisions. Among those which exhibit the im. perfect fifth stamen, are the Trumpet-flower, Foxglove, and Penstemon.

In this order the personate corollas are to be found, or such labiate flowers as have closed lips. Fig. 117, C, represents a flower of this kind; at d, is the pistil, shewing the capsule, or that the seeds are angiospermous. It should be observed that not all the flowers of this order are labiate; some few may

be found with bell-form, and funnel-form corollas. Plants of this order differ much in their natural characters, from those of the order Gymnospermia. None of them are used in preparations for food, as are the Thyme and Savory of the first order, but many of

them possess powerful medicinal properties, as the foxglove (Digitalis), and the cancer root (Epiphegus). They are in general a beautiful collection of plants ; few flowers are more splendid than the Gerardia and the Trumpet flower. These flowers are found in the natural order Personate, of Linnæus.

As plants of this class are numerous in every part of the United States, you will have no difficulty in procuring them for analysis; they are not usually found in blossom until the middle of summer.

[merged small][merged small][graphic][subsumed][ocr errors][subsumed][merged small][ocr errors][merged small]

Siliculosa. The First Order contains plants which produce a short and round pod called a sillicula ; a distinction in this order is made between such plants as have pods with a notch at the top, and such as have none, or are entire.

The pepper grass (Lepidium), and the shepherd's purse (Thlaspi), afford examples of this order. At Fig. 118, d, is a representation of the sillicula or pod of the Thlaspi. The plants found here, belong to the natural family Siliquosa, the properties of which are nutritious and medicinal.

Siliquosa. The Second Order contains such plants as have long and narrow pods; as the radish and mustard. The cabbage (Bras. sica), is an exotic; the turnip is a species of the same genus. These belong to the same natural family as the plants of the first order. The whole are included under the 63d order of of Jussieu, the Crucifera. This order is in Jussieu's 13th class, having seeds dicotyledonous, corollas polypetalous, and stamens hypogynous.

At Fig. 118, a, is the wall-flower (Cheiranthus); the calyx consists of four oblong leaves; the petals are obovate, spreading, with claws as long as the calyx. At b, appear the six stamens divested of the petals; the germ is cylindrical, as long as the stamens; c, shews the silique or pod; the valves are concave and a thin membranous partition divides the silique into two parts.

In this lecture we have pointed out to you the most important characters of the two classes, which depend upon considera. tions derived from the number and comparative length of the stamens; the one class having four and the other six stamens of varying lengths. Both classes we found to have two or. ders, not as in the preceding classes, depending upon the styles; but in the one class, on the situation of the seed as lying in the calyx, or enclosed in a seed vessel ; in the other class, from the comparative length of the pericarp or pod.



We are now to consider the brotherhoods, as the names of the 15th and 16th classes signify; Monadelphia meaning one,

Order Siliculosa—Order Siliquosa-Recapitulation—The Brotherhoods.


and Diadelphia two brotherhoods, in allusion to the manner in which the filaments are connected in one or two sets. The orders in these classes are arranged according to the number of stamens ; a character which distinguishes the first ten classes : but no confusion arises from taking the same character in these classes to distinguish the orders, since in the classes themselves the number of stamens is not reckoned as a mark of distinction. Fig. 119.

In the class Monadelphia we include all such plants as have their filaments united in one set, forming a tube at the bottom of the corolla. - In this union of stamens, this class differs from all the preceding ones; for in those we

found the stamens entirely separate; b

in this, you will observe that the anthers are separate, although the filaments are joined. We cannot in this class, as in the two preceding ones, point out any prevailing form of the

corolla; the mark of distinction here is in some cases rather doubtful, the filaments being sometimes broad at their base, and yet, not entirely connected.

You will recollect that the orders here, depend upon the number of stamens. We have no first order here, for the character of the class is united filaments, and one filament or stamen could not possess this requisite of union.

The Third Order is the first which occurs; this is called Triandria, which you know is the name of the third class, and signifies three stamens. But here are three stamens united by their filaments into a tube. We find in this order a handsome plant, called blue-eyed grass (Sisyrinchium); the three filaments have the appearance of being but one; the corolla is tubular and 6 cleft, style 1, capsule 3 celled; it belongs to the family of sword-leaved plants, Ensatæ. This order contains the tamarind.

Pentandria. The Fifth Order, or five stamens, next occurs; this presents us with the passion-flower (Passiflora), a climbing plant, peculiar to the warm countries of America. “Its immensely long, and often woody branches, attain the summits of the loftiest trees, or trail upon the ground adorned with perennially green, or falling leaves, sometimes palmate, or lobed like fingers, at

Monadelphia-Orders Order Triandria-Passion flower.

« 上一頁繼續 »