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But there is a beautiful regularity in most of Nature's works that may
assist you on this occasion. If the calyx of your flower be divided into five segments, and the corolla be formed of five petals, or divided into five parts, although you find six or seven stamens, it is more than probable that, on further inspection, you will find that it belongs to the fifth class, Pentandria. It is time to conclude this digression, and proceed to the eleventh class–Dodecandria—or twelve stamens. Some flowers in this class contain fewer, and others more than the specified number. All plants are included in it that have any number of stamens from eleven to nineteen inclu.. sive, provided the stamens are disunited. Let us search then for some more invariable characteristic to distinguish this class, and we shall find that the stamens are all fixed to the base or receptacle. In the twelfth class—Icosandria—there should be twenty stamens, or about that number, standing upon the sides of the cup, and sometimes partly on the blossom; whereas the former and following classes are marked by their standing on the receptacle. Observe, as an additional distinction of this class from the next, that the cup consists of one concave leaf, and that the petals are likewise fixed by their claws to the sides of the cup.
Many stamens, from twenty to any number, are found in the thirteenth class—Polyandria—fixed on the base or receptacle. The flowers of this class have either a calyx, consisting of several folioles, or none at all.
In the preceding classes no attention has been paid to the length of the stamens, but they have been supposed to be all nearly equal in that respect. The distinctive marks of the next two classes depend chiefly on such length.
The fourteenth class-Didynamia, or two powers—will present you with flowers containing four stamens ranged in one row, the inner pair shorter than the outer one. The essential marks of this class consist in the proportionable arrangement of four stamens, as I have already expressed,
accompanied with one pointal, and invested with an irregular monopetalous corolla. Those flowers that are called labiate, or lip-shaped, as well as the personate, or masked flowers, are included in this class : those of the first kind have two lips, the one projecting over the other, forming, as it were, a shelter from rain, &c., to the parts of the fructification. The lips are generally closed in the personate corollas, and entirely conceal the stamen and pointal from sight.
Class the fifteenth-Tetradynamia. The meaning of this long word is the power of superiority of four, and accordingly its character is distinguished by six stamens, four of which are long, and the remaining two are short. It is chiefly composed of cross-shaped flowers. The five following classes are not distinguished by the number of the stamens, but by their situation. The union or adhesion of either their anthers or filaments to each other, or to the pointal, decides to which class they belong.
The sixteenth class-Monadelphia, or one brotherhood. In this class the filaments are united at the bottom, but separate at the top, as in the mallow and geranium.
The seventeenth class—Diadelphia, or two brotherhoods. The filaments of these flowers are also united at bottom, not into one bundle or brotherhood, but into two, and consists of the papilionaceous, or butterfly-shaped flowers.
The eighteenth class—Polyadelphia, or many brotherhoods. The filaments in this class are united at the bottom only, into three or more bundles or brotherhoods.
The nineteenth class-Syngenesia, is composed of flowers generally * compound, the essential character of which consists in the anthers being united, so as to form a cylinder, and a single seed being placed upon the receptacle under each floret; perhaps, an example will give you the clearest idea of a compound flower: the thistle is one ready at hand, being composed of small flowers or florets, sitting upon a common receptacle, and enclosed by one common empalement.
* If the order Monogamia of this class be incorporated with Monogynia, as is now generally done, the class is wholly composed of compound flowers,
The twentieth class-Gynandria. Many stamens attached to, and growing upon the pointal itself. Hitherto our attention has been confined to such flowers only as are termed complete, having both stamens and pointals on the same flower ; but the next three classes will furnish us with examples of those which have only the one or the other in the same flower.
The twenty-first class—Monæcia, or one house: the flowers of different kinds are produced in the same habitation, or on the same individual plant. But in the next, or twenty-second class-Diccia, or two houses, the different kinds of flowers (which are distinguished by the names stameniferous, or stamen bearing, and pistiliferous, or bearing pistils) are produced by different trees or plants of the same species.
The twenty-third class-Polygamia, provides for the only remaining case that can possibly happen, and consists of flowers with stamens and pointals in separate flowers, as well as both in the same flower.
The twenty-fourth class—Cryptogamia ; plants whose flowers are not perceptible by the naked eye, though there is good reason to believe that no plant exists without the essential parts that constitute the flower. The lowest kinds of vegetables are the members of this class, as ferns, mosses, sea-weeds or thongs, and funguses.
To these twenty-four classes, Linnæus has added palmtrees, which do not fall under the description of any of the classes. He calls them Princes of India, bearing their fructi. fication on a spadia or receptacle, within a spathe or sheath. They are remarkable for their prodigious height, distinguished by an unvaried, undivided, perennial trunk, crowned at top by an evergreen tuft of leaves, and rich in abundance of large fine fruit. But since the time of Linnæus, more certain knowledge of them has been obtained, and many of them are arranged in the sixth class.
A FEW BOTANICAL NOTES FOR BEGINNERS. The orders of the first thirteen classes are founded wholly on the number of the pointals, so that by adding gynia, instead of andria, to the Greek words signifying the numbers, you will easily obtain a knowledge of them, as Monogynia, one pointal; Digynia, two pointals; Trigynia, three pointals; Tetragynia, four pointals, and so on. In those cases where the pointals have no apparent styles, the stigmas are to be numbered, which generally adhere to the capsule like small protuberances, as may be observed in the flowers of the poppy.
There is no occasion to count the pointals in the fourteenth class, Didynamia, because all the flowers of the Ringent tribe, including both the labiate and personate flowers, have but one pointal; but there is another obvious difference that presents itself as an assistant in discriminating the orders of this class, for most of the plants that have a labiate flower, have four naked seeds at the bottom of the calyx, and the personate flowers are succeeded by a capsule, containing many small seeds. From this distinction arises an easy and natural division of the fourteenth class into two orders : Gymnospermia, comprehending such as have naked seeds ; and Angiospermia, consisting of those that have their seeds covered, or inclosed in a capsule. The fruit supplies us with marks for the subdivision of the next class, Tetradynamia, in which the flowers also have but one pointal. It is divided into two orders, called Siliculosa and Siliquosa, according as the seed-vessel is a silicle or silique. The plants
of the first order have a silicle, or short roundish seed-vessel or pericarp. Those of the second contain their seeds in a silique, or long slender pod. In the sixteenth, seventeenth, and eighteenth classes, the orders are distinguished by the number of the stamens. TABLE OF THE CLASSES.
EXAMPLES 1. Monandria. One Stamen
Marestail. 2. Diandria Two Stamens.
Speedwell 3. Triandria. Three Stamens
Grasses. 4. Tetrandria Four Stamens. (All of the Teasel.
same length) 5. Pentandria ...... Five Stamens. (Anthers not | Honeysuckle.
united) 6. Hexandria....... Six Stamens. (All of the Hyacinth.
same length) 7. Heptandria Seven Stamens
Winter Green. 8. Octandria Eight Stamens
Mezereon. 9. Enneandria Nine Stamens
Gladiole, 10. Decandria Ten Stamens. (Threads not Pink.
united) 11. Dodecandria Twelve Stamens, or more.
Houseleek. (Fixed to the Receptacle). 12. Icosandria Twenty Stamens. (Fixed Strawberry.
upon the Calyx or Corolla) 13. Polyandria ...... Many Stamens. (Fixed to Poppy.
the Receptacle) 14. Didynamia...... Four Stamens, two longer. Foxglove.
One Pointal. Flowers
ringent 15. Tetradynamia... Six Stamens, four longer. Stock Gilliflower.
One Pointal, Flowers cru.
ciform 16. Monadelphia ... Threads united at bottom, Rose Mallow.
but separate at top 17. Diadelphia .... Threads in two sets. Flowers | Everlasting Pea.
butterfly-shaped 18. Polyadelphia ... Threads in many sets; in St. John's Wort.
three or more sets 19. Syngenesia ...... Anthers united. Five Sta- Dandelion.
mens. One Pointal. Flow
ers compound. 20. Gynandria Stamens upon the Pointal Orchis. 21. Monccia
Stamens and Pointals in sepa- Cucumber.
rate Flowers, upon the
same plant. 22. Diccia
Stamens and Pointals dis- Hop.
tinct, upon different plants 23. Polygamia ...... Various situations. Stamens Ash.
Pointals only, or perfect Flowers
[worts, Mushrooms. 24. Cryptogamia ... | Flowers inconspicuous....... Ferns, Monses, Liver.