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ved from the Greek polus, many, added to gonu, knot, signifying many knots, in allusion to its knotted stems.
The most important characters of this class are a calyx inferior; scarcely any corolla, though some have scales resem. bling petals, which bear the stamens and are alternate with them. In this class we find the family Amaranthi, deriving its name from the genus amaranthus, which has its flowers growing in a spike.
The calyx is monophyllous ; corolla regular or irregular, bearing the stamens, which generally alternate with its segments, when of equal number: germ superior.
The labiate flowers (Labiata), are found here; they are monopetalous, consisting of one piece; they are irregular in their outline and appearance. The term Labiate is derived from the Latin word labia, lips ; the flower appearing to be divided at the top into two parts, resembling the lips of an animal. This natural family is subdivided into ringent or gaping, where the entrance into the corolla is open ; and personate or masked, where the corolla seems closed by a prominent throat or palate.
Botanists have made some confusion in the use of these terms. Linnæus called them all ringent, and then subdivided them into labiate, having lips; and personate, closed lips : most other botanists, following him, have made the same division. You can easily see, that to take for a general term, a word which signifies having a gaping mouth or lips, and then to separate the class thus formed into those which have lips, and those which have lips closed, is inconsistent. Thus instead of following a rule with regard to definitions, that as we proceed in more minute divisions, each branch is to contain all the qualities of the whole, or of the generic term, and some property added to mark a specific difference; in this case, the specific term labiate has a more general signification than the generic term ringent.
We shall consider Labiate as the general term, and divide this tribe of plants into ringent, those that have lips gaping ; and personate, such as have the lips closed or muffled. *
* See Eaton's Botanical Grammar, for the same distinction; also Thornton's Botany.
Characters of class 7th-Amaranthi-Of class 8th-Family Labitə--Two divisions, ringent and personate.
The labiate flowers have mostly four stamens of unequal length, standing in pairs, beneath an arch in the upper lip of the corolla. On account of this circumstance, they are ranked in the class Didynamia.
A few of the labiate plants have but two stamens, and on that account, are placed in the class Diandria, as the sage and mountain mint (Monarda). Here again the artificial system separates a tribe which nature has made strikingly similar. Those of the labiate flowers which have but two stamens, exhibit two other imperfect ones; as if it had been the original design of nature to have given them four stamens. Linnæus remarks that the insects which seem most fond of frequenting these species, have also but two wings; but that by a careful observation, the rudiments of two other wings may be found, concealed under a little membrane. Who shall explain these secret sympathies of nature ? and yet we observe them on
If you examine a labiate flower, as balm or catmint, you will see 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 take the stamens along with it, the filaments being attached to it, as they usually are to monopetalous corollas. The corolla has a circular opening at the bottom, through which the pistil grew from the receptacle. The labiate plants inhabit hills, and plains exposed to the
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, teucrium), they act as tonics and strengthen the digestive organs.
The ringent flowers generally grow in whorls or circles, and 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 herbs which are useful in sickness, as pennyroyal, catmint, horehound, &c.; the scullcap (Scutellaria), which has been said to be a remedy for the hy. drophobia, the modest Isanthus (blue gentian), and a little flower of a most beautiful blue colour called Trichostema (blue curls).
The personate division affords some very splendid flowers, Describe the labiate flowers--Medicinal properties of the labiate plants Plants with ringent flowers-Personate flowers.
as the Painted-cup (Bartsia), the beautiful Gerardia, American fox-glove, and the magnificent Bignonia (Trumpet flower). The plants of this family seem to be somewhat allied to those of the class Pentandria ; in many of these, as in the snapdragon (Antirrhinum), the Penstemon, &c., there exist the rudiments of a fifth stamen, in accordance with the five divisions of the calyx and corolla. Some plants of this division of the Labiate family are poisonous, as the Foxglove and Snapdragon. The pericarp of the Labiate plants is of the genus Cenobion.*
Class 9. Corolla monopetalous, perigynous (around the germ). The calyx is of one leaf, and supports the corolla.
In this class we meet with the family Campanulacæ ; its principal genus is CAMPANULA, a term derived from the Latin, signifying a little bell. The bell-form corollas have mostly a calyx above the germ ; regular corolla, inserted into the top of the calyx ; stamens 5, inserted into the same part, under the corolla, alternating with its divisions ; style one ; stigma from three to five cleft ; capsule usually 3 celled, bursting laterally.
CLASS 10. Corolla monopetalous, epigynous (above the germ). Anthers united.
This class contains several families which may all be inclu ded under the general term compound flowers. This great division of the vegetable world, includes an immense number of important and valuable genera. The term compound, re. lates to the arrangement of the flowers, which are so closely connected, as to have the appearance of one single flower. From the union of their stamens, these flowers are also called Syngenesious. The compound flowers have, by botanists, been distinguished under the three heads, of semi-flosculous (having ligulate florets); flosculous (having tubular forets); and radi. ated, having tubular florets in the centre, and ligulate at the circumference, the latter resembling rays.
The semi-flosculous division contains a milky juice, which is bitter and of a narcotic quality ; as the lettuce (Lactuca), and dandelion; their florets are all of one colour.
The flosculous division usually exhibit in their leaves and roots, a predominance of the bitter principle, as the burdock (arctium); their florets are also of one colour.
* See Mirbel's classification of fruits, order 5 of the class Gymnocarps.
Characters of class 9th-Campanulace--Characters of class tenth-Compound flowers-How divided-Semi-flosculous-Flosculous.
The radiated division is mostly composed of plants called Corymbiferous (from corymb and fero, to bear), because their flowers are corymbs, as the Chrysanthemum, Aster, &c. This division includes many beautiful flowers, with splendid colours; and also affords many medicinal plants, as tansy and bone-set (Eupatorium). The colour of the florets in the disk and ray is often very different in these flowers.
The compound flowers begin to blossom in the latter part of summer, and are found bordering upon the verge of winter. The dandelion is among the earliest flowers of spring, and one of the latest of autumn. The daisy is found in almost every spot which exhibits any marks of fertility.
The dandelion is not a single flower, like a violet or rose, but a crowded cluster of little flowers. The sun-flower is so large and conspicuous as doubtless to have frequently attracted your notice. If you would examine one carefully you would find it to be composed of more than a hundred florets or little flowers, each as perfect in its kind as a lily, having its corolla, stamens, pistil and seed.
We distinguish the Sun-flower into two parts,—the disk, which is the middle of the flower, and supposed to have resemblance to the middle or body of the sun; the ray is the border of the flower, or those florets which spread out from the disk, as rays of light diverge from the sun. The florets in this, as in other compound flowers, do not all begin to expand at the same time, they usually begin at the disk and proceed inwards towards the centre.
If you examine with a microscope, one of the florets of the disk, you will perceive it to be tubular, containing one pistil surrounded by five stamens, which are separate, but the five anthers grow together, forming a tube around the pistil.
It is this union of anthers whịch gives to this kind of compound flowers a place in the class Syngenesia, which name signifies anthers growing together. The florets of the ray are called neutral, having neither stamens nor pistils : the circumstance of neutral florets in the ray, places the sun-flower in the order Frustranea, of the 17th class.
Although the term compound is confined to the flowers of the class Syngenesia, the real circumstance on which the class is founded is not the compound character of the flower, but the union of the anthers. A Clover blossom in one sense, may be said to be compound, as it is a collection of many little flowers compounded or united into one ; but each little floret of the clover has its own calyx ; there is no general calyx enclosing the whole, as in most of the Syngenesious plants, but the florets
are arranged in such a manner as to form a head ; the anthers are separate, the filaments are connected at their sides, and this latter circumstance, together with the papilionaceous form of the corolla, places the clover in the class Diadelphia.
Most of the Syngenesious flowers are composed of two sorts of florets, either tubular, with a toothed margin; or strap shaped (ligulate), appearing flat like a strap, but being also toothed at the edge; the latter are sometimes called Semi-flo. rets, or half flowers.
Analysis of the daisy.
We have, at Fig. 97, a representation of the mountain daisy; we will, in regular order, consider the appearance of its different parts.
1. The Root, a : you will observe this an. swers to the general
description of fibrous, b
the small thread-like parts issuing from the
main root, or radix : b
from these fibres, sometimes spring out little tubercles, it is then said to be,
fibrous tubercled. 2. The Leaves, b, you observe, spring from the root, and are hence called radical ; being undivided, they
are called simple. In a form they are somewhat oyal, with the
narrow end towards the stem; this form is called obovate. The leaves are said to be crenate, on account of the notches upon their margin.
3. The Stem, c, is called a scape, because it springs directly from the root, and bears no leaves; it is said to be naked, having no kind of appendages.