this division proper. In this tribe, the most important genus is Pyrus, which contains the apple and pear. The varieties of these fruits are the effects of cultivation, not the produce of different species. By means of grafting, or inoculation, good fruit may be produced upon a tree which before produced a poorer kind.

Jussieu divided his natural order Rosaceæ into the following sections; the Pomacea, with fruit fleshy, like the apple and pear; the Rosa, having urn-form calyxes; Amygdala, having drupe-like fruits. Order Polygynia.

The rose tribe (Rosaceae) resemble the apple tribe, in the appearance of the blossom, but the fruit, instead of being a Pome, consists, either of nuts containing one-seeded acines, as the rose, or of berries, as the strawberry. The leaves have two stipules at their base. The rose unchanged by cultivation has but five petals. We have few indigenous species of this genus; among these, are the small wild rose, the sweet brier, and swamp rose. Red and white roses are remarkable in English history as emblems of the houses of York and Lancaster; when those families contended for the crown, in the reign of Henry the Sixth, the white rose distinguished the partisans of the house of York, and the red those of Lancaster. Among the nations of the East, particularly in Persia, the rose flourishes in great beauty and is highly valued. The Persians poetically imagine a peculiar sympathy between the rose and the nightingale. The Blackberry (Rubus) has a flower resembling the rose in general aspect; there are several species of the Rubus, one which produces the common blackberry, another the red raspberry, another the black raspberry, and another the dewberry. One species, the odoratus, produces large and beautiful red flowers, the fruit of which is dry and not eatable.

The Strawberry belongs to the same natural and artificial order as the Rose. The gathering of strawberries in the fields, is among the rural enjoyments of children, which in after life are recollected with pleasure, not unfrequently mingled with melancholy reflections, upon the contrast of that happy season, with the sorrows with which maturer years are often shaded. The fruit of the strawberry, as was remarked in the classification of fruits, is not properly a berry, but a collection of seeds, imbedded in a fleshy receptacle.

Icosandria furnishes us with a great variety of fine fruits, more perhaps than any other of the artificial classes. A great proportion of the genera to be found in this class, are natives of the United States.

LECTURE XXXI.

CLASS XII.-POLYANDRIA.

In this class we find the stamens separate from the calyx, and attached to the receptacle or top of the flower-stem. The number of stamens varies from twenty to some hundreds. This class does not, like the one we have last examined, contain many_delicious fruits, but abounds in poisonous and active vegetables. The mode of insertion of the stamens is to be regarded in considering the wholesome

Order Pomaceæ-Pyrus, varieties by grafting-Order Rosaceæ divided into sections -Rose tribe-Blackberry-Strawberry-Class Polyandria.

Fig. 136.

a

qualities of plants; it is asserted that no plant with the stamens on the calyx is poisonous; we know that many with the stamens upon the receptacle are so.

Order Monogynia.

We find in the first order some flowers of a curious appearance, as the Mandrake, or Mayapple, (Podophyllum ;) the distinction between this and the mandrake of the ancients, was remarked under the class Pentandria. This plant is very common in moist, shady places, where you may often see great numbers growing together; each stem supports a large white flower, and two large, peltate, palmate leaves; its yellow fruit is eaten by many as a delicacy; the root is medicinal.

The Side-saddle flower (Sarracenia) is a curious and elegant plant; it has large leaves proceeding directly from the root. These leaves form a kind of cup, capable of containing a gill or more of water, with which liquid they are usually filled. The stem is of that kind called a scape, growing to the height of one or two feet, bearing one large purple flower. This plant is found in swamps; its common name, Side-saddle flower, is given in reference to the form of its leaf. It is sometimes called Adam's cup, in reference also to the shape of the leaf. No foreign plant, as an object of curiosity, can exceed this native of our own swamps; it is well worth the trouble of cultivation by those who are fond of collecting rare plants.*

The white Pond lily (Nymphea)† is a splendid American plant, very fragrant, and with a larger leaf than almost any other northern plant. This flower closes at evening and sinks under the water; at the return of day, its blossoms rise above the surface and expand. The yellow Pond lily, (Nuphar,) though less showy, is equally curious in its structure.

In this artificial class and order is the Tea-tree, (THEA ;) of this plant there are two species, the bohea tea, (bohea,) and the green tea, (viridis.) It is a small evergreen-tree or shrub, much branched, and covered with a rough, ark-coloured bark. The flowers are white; the leaves are lanceolate and veined; the capsule or seed vessel is three-celled, opening; the seeds are three, oblong and brown. This shrub is a native of China and Japan. Some suppose that all the teas are taken from the same species, and that the different flavour and appearance of them depend upon the nature of the soil and culture, and the method of preparing the leaves. On account of the secret and jealous policy of the Chinese, the natural history of the Tea plant is less known than might be expected from its very general use. The Chinese begin in February to gather the tea leaves, when they are young and yet unexpanded. The second collection is made in April, and the third in June. The first gathering, which consists only of the young and tender leaves, is the Imperiai Tea; the other two kinds are less odorous: the last collected is the coarsest and cheapest kind. Tea was introduced into Europe by the Dutch East India Company, in the year 1666, when it sold for

*See Plate iii. Fig. 5.

† An extensive locality of this plant exists upon the Saratoga lake. I have seen its surface for a quarter of a mile whitened by these lilies, occasionally intermixed with the yellow lilies, and the rich blue of the Pontederia, another beautiful aquatic plant.

Order Monogynia-Podophyllum--Sarracenia-Pond lilies-Tea-tree.

sixty shillings a pound, and for many years its great price limited its use to the most wealthy.

The poppy (Papaver) is a fine example of this class and order. Its numerous stamens standing upon the receptacle around the base of the germ, and its large stigma, with the two sepals of a caducous calyx, are conspicuous characters. Single poppies have but four petals; but the change of stamens to petals is very common in this flower, and most of the cultivated poppies are double. From the papaver somniferum is obtained the opium of commerce. The juice which issues from incisions in the green capsules, is dried in the sun, and usually made into cakes. Six hundred thousand pounds of this drug are said to be annually exported from the banks of the Ganges. The narcotic property of opium renders it highly valuable as a medicine. Why it is that certain substances, acting upon the human system, have power to affect the mind, no physiologist has yet been able to explain. But in the power of fermented liquors to produce changes in the mind, or of opium to lull its faculties into temporary oblivion, there is nothing more wonderful, than that the presence of light should produce vision, or the vibrations of the air, sound. All are equally beyond our knowledge; we may trace a series of organic changes, but the last link of the chain, that which connects body and soul, is concealed from our observation. Though narcotics can for a time,

"Rase out the written troubles of the brain,
And, with a sweet oblivious antidote,
Cleanse the full bosom of that perilous stuff
Which weighs upon the heart,"

yet, they who attempt to drown sorrow by artificial means, whether of the intoxicating bowl or the stupifying opium, find their sensibilities return with aggravated terrors. When properly used to allay bodily anguish, the product of the poppy may be considered one of our greatest blessings but like all our blessings, it may, by its abuse, be made a curse.

The genus Citrus, which contains the orange and lemon, is found here. Jussieu places this in his order Aurantia, or golden fruits. The fruit is a berry with a thick coat. It furnishes citric acid.

Few valuable fruits, with the exception of this genus, are found in the class Polyandria.

Order Di-pentagynia.

The four orders following Monogynia, are, as in the preceding class, united into one, called as before, Di-pentagynia, having from two to five styles.

We find here some plants of a poisonous nature, as the Larkspur, Monk's-hood, and the Columbine; these belong to the natural order Ranunculacea, which contains also the Ranunculus or crow-foot, the anemone and gold-thread, (Coptis.)

In the same natural and artificial order we find the Peony, (Paonia,) a large and showy flower, which, in its native state, has a calyx with 5 sepals, a corolla with 5 petals; 2 or three germs, each crowned by a stigma; the capsules or carpels are the same in number as the germs; each contains several seeds; this flower is remarkable for becoming double by cultivation.

Order Polygynia.

This order is divided into two sections: 1st, flowers with no ca

Poppy-Opium-Power of opium and fermented liquors to affect the mind-Genus Citrus-Order Di-pentagynia-Natural order Ranunculaceae-Peony-Order Polygynia.

lyx or perianth; 2d, with a perianth. In the first section we find several interesting native plants. The Clematis or Virgin's bower is a beautiful climbing plant, which supports itself by winding its petiole 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 appearance after the blossoms have faded. This plant contains many species, and is cultivated both in this country and in Europe. At fig. 136, a, is a flower of the Clematis; b, represents its receptacle with numerous styles proceeding from it, and the petal and stamens separated, showing them to be inserted upon the receptacle.

The HELLEBORE (Helleborus) is an exotic much spoken of by classical writers. Hippocrates, one of the most ancient physicians, remarked upon its qualities; it grew about Mount Olympus, and was early known 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 region of the Magnolia grandiflora extends from South Carolina 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 those which we have noticed.

LECTURE XXXII.

CLASS DIDYNAMIA AND TETRADYNAMIA.

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 regarded, but new circumstances of distinction are introduced, viz. the seeds being enclosed in a pericarp, or destitute of this covering, and the comparative length of pods.

α

Fig. 137.

CLASS XIII.-DIDYNAMIA.

This class has flowers with 4 stamens, two of which are longer than the other two; the stamens stand in pairs; the outer pair being longer, the inner pair shorter and converging.

The class contains two orders, Gymnospermia, (seeds naked or without a pericarp,) and Angiospermia, (seeds enclosed in a perricarp.)

The labiate flowers are found in this class; these are monopetalous, and irregular in their outline. The term labiate is derived from the Latin labia, signifying lips; the flowers being divided at the top into two parts, resembling the lips of an animal. This tribe

Clematis--Hellebore-Magnolia-What classes are now considered?-How are their orders distinguished ?-Labiate flowers.

is divided into ringent, or gaping, and personate, or closed. These terms have been used in an indefinite manner. Linnæus called the whole tribe ringent; these he subdivided into labiate and personate. This division is illogical, since the specific term labiate, having lips, has a more general signification than the generic term ringent, lips gaping.

A few of the labiate flowers having but two stamens, are placed in the class Diandria, as the sage and mountain-mint. Yet they have, besides their two perfect stamens, the rudiments of two others, as if nature had designed them for didynamous plants. Linnæus remarks, that the insects most fond of frequenting these plants have but two perfect wings; while the rudiments of two other wings may be found concealed under a little membrane;-How wonderful are the sympathies of nature!

When you examine a labiate flower, as balm or catmint, you will observe that the arched upper lip of the petals covers the stamens, and that the lower lip hangs down, so that you can see the inside of the corolla. If you pull out the corolla, you will find the stamens attached to it, as they usually are to monopetalous corollas. The corolla shows an aperture at the base through which the pistil ascended.

The labiate plants inhabit hills and plains exposed to the sun. The aroma which escapes from their flowers, denotes their stimulating medicinal properties. Their action upon the animal economy differs according to the quantity of essential oil and of bitter principle which they contain; when the former prevails, as in mint, they are aromatic and stimulating; when the bitter principle is in excess, as in germander, they act as tonics, and strengthen the digestive organs. The pericarp of the labiate flowers belongs to Mirbel's class of fruits, called cenobion.

Order Gymnospermia.

The plants in this order have labiate corollas of the ringent kind; the seeds are four, lying uncovered in the calyx; the flowers grow in whorls; the stem is four-angled, and the leaves opposite. The calyx is either five-parted, or the upper part consists of two divisions, called lips.

At Fig. 137 is a flower of the genus Tencrium, (germander;) the corolla is ringent, the upper lip two-cleft, the lower lip three-cleft; the stamens and pistils are incurved; the stamens are exsert through the cleavage on the upper side;--b, shows the pistil with its four uncovered, or gymnospermous seeds.

The ringent flowers generally grow in whorls at the upper part of an angular stem, the leaves standing opposite. These plants are never poisonous. Among them we find many aromatic plants, the peppermint, lavender, savory, marjorum, thyme, &c.; also many medicinal herbs, as pennyroyal, catmint, horehound, &c.; the scullcap, (Scutellaria,) which has been said to be a remedy for the hydrophobia, the modest Isanthus, (blue gentian,) and a little flower of a most beautiful blue colour, called blue curls, (Trichostema.)

Order Angiospermia.

The second order contains those plants which have many seeds, contained in a capsule. Plants of this order appear to have an affinity with some families of the class Pentandria. Many in addition

How divided?--Are all labiate flowers in the class Didynamia ?-What is said of the properties of these plants ?-What kind of pericarps have the labiate flowers?What plants in the order Gymnospermia ?-Describe Fig. 137-What is said of the ringent flowers ?-How is the order Angiospermia distinguished?