網頁圖片
PDF
ePub 版

Fig. 132.

LECTURE XXVIII.

CLASSES OCTANDRIA AND ENNEANDRIA.

CLASS VIII.-OCTANDRIA.

Order Monogynia.

THE eighth class, although not large, contains some beautiful and useful plants. One of the first which we shall notice is the scabish, (Enothera,) sometimes called evening primrose. Many species of this are common to our country; some grow to the height of five feet. The flowers are generally of a pale yellow, and in some species they remain closed during the greater part of the day, and open as the sun is near setting. This process of their opening is very curious, the calyx suddenly springs out and turns itself back quite to the stem, and the petals being thus released from the confinement in which they had been held, immediately expand. There are few flowers which thus hail the setting sun, though many salute it at its rising. The flowers of the Enothera are thickly clustered on a spike, and it is said that "each one, after expanding once, fades, and never again blossoms."* This singular flower has been observed in dark nights to throw out a light resembling that of phosphorus. The regularity of its parts render it a good example of the eighth class; the different parts of its corolla preserve in their divisions the number four, or half the number of stamens. It has 4 large, yellow petals, the stigma is 4-cleft, capsule 4-celled, 4-valved, the seeds are affixed to a 4sided receptacle.

The evening primrose belongs to an order of dicotyledonous plants called Onagræ;† the characters of which, are four petals above the calyx; stamens inserted in the same manner, and equal or double the number of petals; the fruit a capsule or berry. To this natural order belongs the willow herb, (Epilobium,) a very branching plant with red flowers and feathery seeds. The cranberry (Oxycoccus) also belongs to the same family, but having ten stamens, is placed in the class Decandria; a natural affinity being made to yield to the artificial system. The fruit of the cranberry consists of large scarlet berries, which contain tartaric acid. The flowers are white, they have a four-toothed calyx, and corolla fourparted. It is found in swamps in various parts of North America. The ladies' ear-drop, Fuschsia, (see fig. 131,) is a beautiful exotic. It has a funnel-form calyx, of a brilliant red colour; the petals are almost concealed by the calyx, they are purple, and rolled round the stamens, which are long, extending themselves beyond the coloured calyx. This plant is a native of Mexico and South America, except one species, from the Island of New Zealand. Ten species are said, by horticulturists, to be cultivated; but some of them are; probably, rather varieties, than distinct species.

The heath‡ (Erica) is not known to be indigenous to this country; many species have been introduced. The common heath

* W. Barton.

+ The common French name for the evening primrose, is Onagré. The term heath is said to have originated from an old Saxon word, alluding to the heat which the plant affords as fuel; it is used in England for heating ovens.

Evening Primrose-What are the characteristics of the natural order Onagræ, and what plants belong to it ?-Ladies' ear-drop-Heath.

(Erica cinerea) has bell-form flowers, small and delicate, with the colour pink, or varying into other colours; the flowers intermixed with the delicate green leaves produce a fine effect. The kind of soil necessary to the growth of the heath, is the peat earth, so common in England and Scotland, in which countries this plant abounds; thus Scott says of his Lady of the Lake,

"A foot more light, a step more true,

Ne'er from the heath-flower brush'd the dew."

In the Highlands of Scotland, the poor make use of the heath to thatch the roofs of their cottages; their beds are also made of it The field in which this plant grows is termed a heath or heather. "The Erica here,

That o'er the Caledonian hills sublime,

Spreads its dark mantle, where the bees delight
To seek their purest honey, flourishes;
Sometimes with bells like amethysts, and then
Paler, and shaded, like the maiden's cheek,
With gradual blushes; other while, as white
As frost that hangs upon the wintry spray.'

[ocr errors]

The Daphne is a rare plant; one species is called the Lace-bark tree, from the resemblance of its inner bark or liber to net-work or lace. This bark is very beautiful, consisting of layers which may be pulled out into a fine white web, three or four feet wide; this is sometimes used for ladies' dresses, and may even be washed without injury. Charles I. of England, was presented by the governor of Jamaica with a cravat made of this web. The plant is a native of the West Indies.

The Nasturtion (Tropæolum) is a very commonly cultivated exotic. It has not a regularity of parts; the divisions are not four or eight, which we might expect from its eight stamens, but the calyx is either four or five-parted, and the corolla is five-petalled. The fruit consists of three seeds; these are used for pickles. "The generic

name (Tropaeolum) signifies a trophy-plant"; "this alludes to its use for decorating triumphal arches, or to the resemblance of its peltate leaves to shields as well as its flowers to golden helmets pierced through and stained with blood."*

Order Trigynia.

This order contains the Buckwheat, (Polygonum,) which was classed by Linnæus in the same natural order as the dock, pigweed, &c., "having flowers destitute of beauty and gay colouring." The genus is extensive, containing many plants which are considered as common weeds. The fagopyrum is the true buckwheat; the meal obtained by grinding its seed, is much esteemed for cakes; these are called slap-jacks in New-England, in England, crumpits. The Polygonum is variable in its number of stamens; the seed is a triangular nut.

Order Tetragynia.

We here find the beautiful plant, Paris, which is said to have been named after a prince of ancient Troy, remarkable for his beauty. In every part of the flower there is the most perfect regularity; the numbers four and eight prevailing in the divisions. It has 8 stamens, 4 pistils, 4 petals, 4 sepals, a 4-sided and 4-celled pericarp, which contains 8 seeds, and 4 large spreading leaves, at a little distance below the flower. The colour of the whole is green. The plant is said to be narcotic. It is a native of England.

*Sir J. E. Smith.

Lace-bark tree-Nasturtion-Second order-Third order-Fourth order.

Fig. 133.

CLASS IX.-ENNEANDRIA.

Order Monogynia.

This is also a very small class. In the first Order we find the genus Laurus, which includes the cinnamon, bay, sassafras, camphor, spice-bush, &c. The bay (Laurus nobilis) is a native of Italy; the Romans considered it a favourite of the Muses. The emperor Tiberius wore it not only as a triumphal crown, but as a protection against thunder; it being thought that Jupiter had a particular regard for the plant. The laurel, as well as the olive, was considered as an emblem of peace; it was sometimes called laurus pacifera, the peace-bearing laurel. Branches of laurel carried among contending armies, were considered as a signal for the cessation of arms. Poets crowned with laurel, were called laureates. Camphor is the produce of the LAURUS camphora, a large tree which grows in Japan. "The LAURUS cinnamomum is a tree which grows to the height of twenty feet; it sends out numerous branches crowned with a smooth bark. The leaves are of a bright green, standing in opposite pairs. The petals are six, of a greenish white colour. The fruit is a pulpy pericarp enclosing a nut. This tree is a native of Ceylon, where it grows very common in woods and hedges. The imported cinnamon is the inner bark (liber) of the tree; it is remarkable that the leaves, fruit, and root, all yield oil of very different qualities. That produced from the leaves is called the oil of cloves; that obtained from the fruit is of a thick consistence, very fragrant, and is made into candles for the use of the king; the bark of the roots affords an aromatic oil, called the oil of camphor. The Sassafras-tree (LAURUS sassafras) is a native American plant; when first introduced into Europe, it sold for a great price, the oil being highly valued for medicinal uses. It grows on the borders of streams and in woods; it is often no larger than a shrub; its flowers are yellow; its fruit, blue-berries. The LAURUS benzoin, called Spice-bush, has scarlet berries, and is an aromatic plant."

[graphic]
[ocr errors]

Fig. 133, a, represents a flower of the Butomas, (flowering rush ;) the petals are six; they are ovate. The umbellatus is the only species known; the flowers grow in rose-coloured umbels. It is found in wet grounds, and near the margin of lakes and ponds.

Order Trigynia.

The third Order presents us with but one genus; but this renders the order important; it is the Rhubarb, (Rheum.) In one species, the RHEUM tartaricum, the leaves are acid, and on this account, when young, they are used for making pies. This plant is a native of Tartary, but now common in our gardens. The RHEUM palmatum is the plant which produces the medicinal rhubarb; this is obtained from the roots, which are thick, fleshy, and yellow. This plant is cultivated in England, and is remarkable for the rapidity of its growth. An English writer, asserts that its stem has been known to grow more than eleven feet in three months; its leaves are five feet in circum* Woodville. † See also Appendix, Plate viii. Fig. 4. + Woodville. Class Enneandria-Different species of the genus Laurus-Describe the different species of Laurus-Butomas-What genus is found in the order Trigynia?

ference; the root grows to a great size; some roots have been imported from Turkey which weighed more than seventy pounds. At Fig. 133, b, is a flower of the genus Rheum.

[ocr errors]

We have dwelt somewhat at length upon exotics, because they are seldom described in botanical works in common use. If you become interested in the study of plants, you will naturally wish to know something about those which you are in the habit of using for food, or medicine, or to which, as in the laurel of the ancients, allusions are often made in the books which you read. But you cannot become practical botanists without much observation of our native plants. You must seek them in their own homes, in the clefts of rocks, by the side of brooks, and in the shady woods; it is there you will find nature in her unvitiated simplicity. We do not go to the crowded city to find men exhibiting, undisguisedly, the feelings of the heart. The flower transplanted from its rural abodes, exhibits in the splendid green-house, a physical metamorphosis, not less remarkable than the moral change which luxury too often produces upon the character of man.

LECTURE XXIX..

CLASS X.-DECANDRIA.

PLANTS of this class have ten stamens, but this circumstance alone would not distinguish them from some of the other classes; the number of stamens must not only be ten, but these must be distinct from each other; that is, neither united by their filaments below, nor by their anthers above. Other classes, Monadelphia, Diadelphia, Gynandria, and the two classes with the stamens and pistils on separate flowers, may also have ten stamens; but circumstances respecting the situation of these organs distinguish these classes from each other.

α

Order Monogynia.

In the first Order of the tenth class, we find some plants with papilionaceous corollas; these, because their filaments are not united, are separated from the natural family to which they belong, and which are mostly in the class Diadelphia. Among those which are thus removed from the class where from their general appearance they might have been looked for, is the wild indigo, (Baptisia,) a handsome plant with yellow flowers, two or three feet in height, and very branching; the stem and leaves are of a bluish green. This is found in dry sandy woods; it was used as a substitute for indigo during the time of the American revolution.

[graphic]

The Cassia fistula, a native of the Indies contains in its legume a pulp which is much valued in medicine, and known by the name of Cassia. The CASSIA Senna furnishes the senna used in medicine; this species grows in Egypt and Arabia. One species, the CASSIA marylandica is called American senna, on account of its medicinal

Concluding remarks-Are there any classes except the tenth, in which the flowers have ten stamens ?-Order Monogynia-Wild Indigo-Cassia.

qualities. Another species, nictitans, has small yellow flowers, and beautiful pinnate leaves, which remain folded at night; it shrinks back from the touch, for which reason it is called the American sensitive plant.

A plant, called by the Indians, Red-bud, (CERCIS canadensis,) belongs to this class. It is a large tree, appearing as early as April, loaded with clusters of fine crimson flowers; the leaves, which are large and heart-shaped, do not appear as early as the blossoms. The beautiful aspect of the tree attracts to it many insects, particularly humblebees. A botanist says, (6 I have often observed hundreds of the common humblebees lying dead under these trees while in flower." This is not the only example of fatal consequences which result from trusting too much to external appearances! tree is not improperly called Judas' tree.

This

The three genera of plants which we have now noticed, bear fruit in that kind of pod called a legume; this is the case in general with the papilionaceous flowers.

The rue (Ruta) is an exotic, which gives name to one of Jussieu's natural orders called Rutacea; these plants have a monosepalous calyx; five petals, alternating with the lobes of the calyx; the germ is large and superior, (See Fig. 134, a.)

At b, Fig. 134, is a representation of a flower of the Saxifraga, a very extensive genus; one species of which, an exotic, sometimes called beefsteak geranium, is much cultivated as a green-house plant; it is very hardy; its leaves are roundish and hairy; it sends forth creeping shoots.

This class and order presents us with the Wintergreen tribe; plants which are more or less shrubby, with monopetalous, bell-form corollas and evergreen leaves. In shady woods, where the soil is loose and rich, we find, in June and July, the spicy wintergreen, (Gaultheria,) a perennial plant which grows to the height of eight or ten inches; the pleasant taste of the leaves and fruit of this plant, is well known to the children of this country; the drooping blossom is very delicate and beautiful, consisting of a bell-form corolla, (not unlike the lily of the valley,) the colour of which is tinged with pink. Though you may have often enjoyed eating the fruit and leaves of the wintergreen, you will experience a delight which this mere pleasure of sense could not have afforded, when in your botanical rambles in the woods you chance to meet with this plant in blossom, with its little flowers just peeping out from a bed of dry leaves; you may then have the pleasure of a beautiful object of sight, with the intellectual gratification of tracing those characters which give it a definite place in scientific arrangement. Among the wintergreen tribe are two genera, Pyrola and Chimaphila, which by some botanists have been included under one; but they appear to be sufficiently distinct from each other to constitute a separate genus. These plants were classed by Linnæus in the natural order Bicornes, or two horns, alluding to the two protuberances, like straight horns, which appear on their anthers.

A great proportion of the plants in the first order of the tenth class are to be found in shady woods in June and July. We can here enumerate but few of them. We will, however, mention the Monotropa, a most curious little plant;-several stems of a few inches in height, form a cluster; each stem supports a single flower,

* W. P. C. Barton.

Cercis-Natural order Rutacea-Saxifraga-Wintergreen tribe-Monotropa, or Indian-pipe.

« 上一頁繼續 »