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BOTANICAL EXPLANATIONS.

FLOWERS.

There are seven elementary parts in a flower-or, properly speaking, flower and fruit.

1. Calyx. The outer or lower part of the flower, generally not colored.

2. Corol. The colored blossom of the flower, within or above

the calyx.

3. Stamens. The mealy or glutinous knobs, generally on the ends of slender filaments.

4. Pistil. The central organ of a flower; the base of this becomes the pericarp or seed.

5. Pericarp. The covering of the seed, whether pod, shell, bag, or pulpy substance.

6. Seed. The essential part, containing the rudiments of a new plant.

7. Receptacle. The base which sustains the other six parts,

being at the end of the stem.

Any accidental appendage is a nectary. The form and positions of these organs, and of no other part, are employed in distinguishing the Classes, Orders, and Genera.

Double flowers are formed by changing the stamens into petals. Botanists term these vegetable monsters.

INFLORESCENCE;

OR, MANNER OF FLOWERING.

1. Whorl. An assemblage of flowers surrounding the stem or its branches, constitute a whorl or ring: this is seen in the Mint and many of the labiate plants.

2. Raceme, or cluster, consists of numerous flowers each on its own stalk or pedicle, and all arranged on one common peduncle; as, a bunch of Currants.

3. Panicle bears the flowers in a kind of loose subdivided bunch or cluster, without any regular order; as in the Oat. A panicle contracted into a compact, somewhat ovate form, as in the Lilac, is called a Thyrse, or bunch; a bunch of Grapes is a good example.

4. Spike. This is an assemblage of flowers arising from the sides of a common stem: the flowers are sessile, or with very short peduncies; as, the Wheat and the Mullein.

5. Umbel-several flower-stalks, of nearly equal length, spreading out from a common centre, like the rays of an umbrella, bearing flowers on their summits; as, Fennel and Carrot.

6. Cyme resembles an umbel in having its common stalks all spring from one centre, but differs in having those stalks irregularly subdivided; as, the Snow-ball and Elder.

7. Corymb, or false umbel-when the peduncles rise from different heights above the main stem; but the lower ones being longer, they form nearly a level, or convex top; as, the Yarrow.

8. Fascicle-flowers on little stalks variously inserted and subdivided, collected into a close bundle, level at the top; as, the Sweet William.

9. Head, or tuft, has sessile flowers heaped together in a globular form; as in the Clover.

10. Ament, or catkin, is an assemblage of flowers composed of scales and stamens, arranged along a common thread-like receptacle; as in the Chestnut and Willow.

11. Spadix is an assemblage of flowers, growing upon a common receptacle, and surrounded by a spatha, or sheath; as in the Egyptian Lily.

CLASSES AND ORDERS.

THE explanations of these must necessarily be very brief; my aim being rather to stimulate curiosity respecting the subject of Botany, than to impart instruction in the science. A few general facts, and a few of the first terms, are all that can be given.

Flowers in the Linnæan system are divided into twenty-four Classes. These Classes are divided into Orders; Orders into Genera; Genera into Species; Species are frequently changed into Varieties.

The first ten classes are distinguished by the number of their stamens; thus,

1. Monandria,-1 stamen,-Flowering Reed is the only one of this class given.

2. Diandria,-2 stamens,-Lilac, Sage, Jasmine, etc 3. Triandria,-3 stamens,-Crocus, Iris, Oat, etc.

4. Tetrandria,-4 stamens,-Witch-Hazel, Holly, etc. 5. Pentandria,-5 stamens,-Violet, flax, Woodbine, etc. 6. Hexandria,-6 stamens,-Lily, Sorrel, Aloe, etc. 7. Heptandria,-7 stamens,-Horse-chestnut, etc. None of this class given.

8. Octandria,-8 stamens,-Nasturtion, etc.

9. Eneandria,-9 stamens,-Laurel, etc.

10. Decandria,-10 stamens,-Rue, Pink, Hydrangea. 11. Dodecandria,-12 to 19 stamens,-Mignonette, etc. 12. Icosandria,-20 or more, standing on the calyx. Rose, etc. 13. Polyandria,-always 20 or more, on the receptacle,Butter-cup, Larkspur, Peony, etc.

14. Didynamia,-4 stamens, 2 of them uniformly the longest, -Fox-glove, Balm, Thyme, etc.

15. Tetradynamia,-6 stamens, 4 of them uniformly the longest,-Gilly-Flower, Honesty, Queen's Rocket, etc. 16. Monodelphia,- -stamens united by their filaments in one set, anthers being separated,-Geraniums, Hibiscus, etc. 17. Diadelphia,-stamens united by their filaments in two sets, -flowers papilionaceous, or butterfly-shaped. 18. Polydelphia,-stamens in two sets, united at the bottom by the filaments, Orange, St. John's Wort, etc.

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