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4. The Calyx, d, is said to be hemispherical, or a half sphere; it is common, that is enclosing many florets; the leafets of the calyx, sometimes called scales, are equal, or of the same size.

5. The Corolla, e, is compound, having many florets on one receptacle, radiate, having rays; the florets of the disk are Fig. 98.

tubular (Fig. 98, a,); they have both stamens and pistils; they are funnel shaped, and five tooth. ed; the florets of the ray, b, are flat, and have pistils without sta

mens.

6. The Stamens, c, are five, uni. ted at the summits by their anthers, forming a tube.

7. The pistil, in the disk florets, d passes up through the tube formed

by the anthers, d; the stigma is parted into two divisions, which

are reflexed (bent back); the pistil in the ray florets passes up through the tube of the floret.

8. The plant has no pericarp, or seed vessel, the seeds grow upon the receptacle, e, they are single and shaped some. what like an egg; they are also naked, that is, destitute of the downy plume called egret, which is seen upon the dande. lion, and many other of the syngenesious plants.

9. The receptacle is conical, or in shape resembles a sugar loaf; it is dotted with little holes: these are the places in which the seeds were fixed; the appearance of the receptacle, whether naked or chaffy, is very important to be observed in the syngenesious plants; it sometimes constitutes a distinction between genera. . The seed belongs to the genus of fruits, Cypsela."

The botanical name of the daisy is BELLIS perennis. It be. longs to the class 17th, Syngenesia, because the anthers are united; order 2d, Superflua, because the pistils in the ray are superfluous, having no stamens. The generic name Bellis, is from an ancient Latin word, belles, handsome; from which comes also the French word bel; the specific name, perennis, signifies that it is a perennial plant, or one whose roots live

several years.

The common name, daisy, is derived from a property, which many of the syngenesious plants possess, of folding up their petals at the setting of the sun, and expanding them with its rising. The poet Chaucer, who lived in the fourteenth century, is said to have first noticed this circumstance, and to have called the flower Day's-eye. The French name for the daisy is La belle Margarite.

* See Mirbel's Classification of fruits, order 1 of the class Gymnocarps.

Describe tho Calyx of the Daisy-The Corolla—The Stamens—The pistilThe Pericarp--The receptacle-Botanical name, elass and order of the daisy Derivation of the botanical name The common name.

CLASS 11. Corolla monopetalous, epigynous (above the germ). Anthers distinct.

The most important family in this class is the Rubiacea, in which we find the Peruvian bark, (Cinchona,) a native of South America; it was discovered by the Jesuits, and by them, introduced into France towards the middle of the eighteenth century. It was at first called Jesuit's bark. Some of the French chemists have recently discovered in this bark two alkaline principles, which they call quinine and cinchonine ; these alkalies united to sulphuric acid, forming sulphates, are found to be of great use in medicine.

The family Rubiaceæ contains some other valuable medi. cinal plants; and some which are of great use in dyeing, as the Rubia tinctoria, which gives to wool a fine red colour. This family contains a genus very common in our fields, the Galium, and some other important genera, not distinguished by striking peculiarities of natural character.

CLASS 12. Corolla polypetalous, stamens epigynous (above the germ).

This class presents us with one important family, the Umbel. late (Umbellifera).

The plants of this natural family are found in the artificial class Pentandria; they derive their name from the Latin word umbella, an umbrella, on account of the manner in which the peduncles or flower stalks extend from the main stem.

The umbellate plants are mostly herbaceous; those which grow on dry ground are aromatic, as dill, fennel, and caraway; those which grow in wet places, or the aquatic species, are among the most deadly poisons, as water-hemlock, &c. Plants of this family are not, in general, so beautiful to the sight, or so interesting, as objects of botanical analysis, as many others. *

*“ Botanists in general shrink from the study of the Umbelliferæ ; nor have these plants much beauty in the eyes of amateurs ; but they will repay the trouble of a careful observation. The late M. Cusson, of Montpelier, bestowed more pains upon them than any other botanist has ever done; but the world

Characters of Class 11-Rubiaceæ--Peruvian bark-What two alkaline principles obtained from it ?--What term is given to these alkalies when united with sulphuric acid ?-Other genera in the family Rubiaceæ-Charaa ters of Class 12--Umbelliferæ.

The corolla is superior, or over the germ; it consists of five petals, usually with a stamen standing between each petal. From the centre of the flower, arise two styles, which often remain permanent upon the fruit. The general figure of the fruit is oblong or oval; it separates perpendicularly into two seeds, as may be seen in the fennel or dill. The figure, margin, and angles of the seeds are considered as affording proper characters for the distinction of genera ; as in the parsnip, they are flat, in the carrot, bristly, in the hemlock, marked with ridges. Among the plants of this family which are used as articles of food, are the carrot, parsnip, celery, and parsley; the aromatics are dill, fennel, sweet cicely, caraway, and coriander; among the poisonous plants, are the conium (poison hemlock), water-parsnip, and the cicuta (water-hemlock). The seed of umbilleferous plants belong to the genus of fruits, Cremocarp.

Class 13. Corolla polypetalous, stamens hypogynous (under the germ).

In this class the principal family is the Cruciform (Crucife. ). In these plants we find such flowers as have a calyx consisting of four leaves, and a corolla composed of four petals; each petal is fastened to the receptacle or bottom of the calyx by a narrow part called a claw; the whole exhibiting the form of a cross; hence the term cruciform, from crur, a

In the centre of the flower is a single pistil, long and cylindrical; the stigma is oblong and divided into two parts, which are reflexed or bent back on each side. Each petal is placed between two leaves of the calyx; alternate position is always seen in flowers where the number of petals equals the number of leaves of the calyx.

The cruciform flowers have six stamens, two of which standing opposite to each other are shorter than the remaining four, which always stand in pairs. This inequality in their length determines them to be in the class Tetradynamia. The germ soon becomes a long pod called a silique, or a short thick one, called silicula ; this difference in the length of the two pods constitutes the distinction of the two orders of the class in which they are placed.

The plants belonging to this class are herbaceous; the leaves are alternate; the cabbage, the mustard, radish, and stock.

cross.

has, as yet been favoured with only a part of his remarks. His labours met with a most ungrateful check, in the unkindness, and still more mortifying stupidity of his wife, who, in his absence from home, is recorded to have de. stroyed his whole herbarium, scraping off the dried specimens for the sake of the paper on which they were pasted ?"--Sir James Edward Smith's Botany.

Characters of Class 13--Describe the cruciform plants.

gilly-flower belong to this family. They are found, on a chemical analysis, to contain some sulphur.

Fig. 99.

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Fig. 99, A, represents a flower of the cruciform family; at B, a, may be seen the stamens arranged in two sets, four being longer than the two at b; at c, are two glands between the short stamens and the germ; at C, is a petal, consisting of a, the border, and b, the claw; at D, is the pod or silicle; a represents the valves, b, the seeds as alternately attached to the edges of the partition or dissepiment which divides this kind of pericarp into two cells.

CLASS 14. Corolla polypetalous, stamens perigynous (around the germ).

In this class we find the family rosacee, having rosaceous corollas; a calyx mostly urn-form ; petals usually 5, inserted into the top of the calyx ; stamens indefinite, generally over 10. The structure of the fruit varies in the apple (Pyrus malus), the fruit is below the top of the calyx and contains many cells; embryo without albumen. The pericarp of the apple is classed by Mirbel in the order Bacca or berry, and the genus Pyridion. The rose belongs to the same natural family as the apple, and gives name to the whole group described under the name Rosaceous.

Examine an apple blossom and a wild rose, and you will perceive the former to be a miniature representation of the lat. ter; their fruits, too, which at first thought might seem to you

Explain Fig. 99 Characters of Class 14-Describe the rosacer-Comparison between the apple and rose.

to be very different, are yet similar; both are crowned with the adhering calyx, and contain many seeds in a pericarp formed by the swelling of the calyx. But in their real value the fruit of the rose bears but a poor comparison with that of the apple, although its blossom is far more splendid ; thus it often is, that beauty seems destined to prove less valuable than more humble qualities.

In the class of plants we are now considering, is found a very large and important family, called Leguminosa (legumi. nous), from the nature of the fruit, which is of that kind called a legume ; the flowers of this family are also called papiliona. ceous, from a Latin word papilio, a butterfly, on account of the supposed resemblance between them and that insect; they are generally flowers with brilliant colouring, and of showy appearance. The sweet pea may be given as an example; this unites to delicacy of colour and beauty of form, a highly fragrant perfume.

Fig. 100.

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Fig. 100 represents the sweet pea (Lathyrus odoratas); at a, is the five toothed calyx; at b, is the upper petal, called the banner; at c, are the wings, or two side petals; at d, is the keel, formed of two petals united by their edges; at e, are the ten stamens, nine united and one separate; at f, is the pistil, the base of which, in process of time, becomes the pod or legume.

The flowers belonging to the family Leguminosæ, are so peculiar in appearance as to make them easily recognized.

Leguminose

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