Imatges de pàgina
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Gather one of the flowering stems of the white or red dead nettle-Fig. 79-the flowers are gathered in clusters around the stem, they are what is called whorled. The term whorl, however,

is applied to leaves as well as to flowers.

In our examination of various plants, our readers must have observed in how many cases the flowerstems-peduncles-or the pedicels, have, at the points where they branch off from the main stem, and elsewhere, leaves, either resembling the other leaves of the plant, or dif78. Composite blos- fering from them in various ways, som of Leopard's Bane becoming less and less leaf-like, till neum). The peduncle they are at length little more than scales, such as we see in the cur

(Doronicum Plantagi

-2-supports a capi

tulum or head-1-
which is made up of a
number of separate rant
blossoms or florets;

Fig. 71 or speedwell

those in the centre 3 Fig. 72. These, corresponding to

constituting the

the ray-4-are ligu

disk. The florets of the stipules of leaves, are called floral late, or strap-shaped. leaves or bracts. As we see in the dead nettle Fig. 79-or the lesser loosestrifeFig. 70-the floral leaves and the ordinary leaves of the plant do not exhibit any difference. In the lime tree Fig. 80-the conspicuous bract is very different from the leaf. In the currant, the bracts, as above observed, are simply scales. A few plants, some species of salvia, have the bracts gaily coloured. In some cases the bracts are additionally distinguished according to their form, &c. Thus, the bracts which surround the umbels of many umbelliferous plants are called the involucres

as

Fig. 98, &c.-so are those named which inclose the flower-head or capitulum of such a plant as the daisy-Fig. 81. The singular hood-like appendage of the curious wake-robin-Fig. 82-is a bract,

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and gets the name of a spathe. the leaf-like appendages to the are also bracts; in the grasses the outer scales or glumes of the spikelets-Fig. 84-are bracts; in the hazel and willow the scales of the catkin are also called bracts.

With the bracts terminates our description of the parts and characters of plants, or rather of such parts and characters as lie upon the surface, and most readily meet the eye of the

In the carex tribe, spikes-Fig. 83

A

81. Blossom of common Daisy

(Bellis perennis), showing the flower-head or capitulum.

common involucre-1-of the

observer. Almost superfluous must the remark be, that in our descriptions we have but skimmed the surface of our subject, we have but given such kind and amount of information as seemed best

82. Blossom of Wake-robin or Cuckoo-pint (Arum maculatum), showing the large bract-1-in this case called a spathe, which surrounds the reprodutive organs, the stamens-2-the pistils-3.

83. Sedge, or carex, showing the leaf-like bracts-3-which are situated at the base of the flower-spikes; the fertile, or pistil, or seed-bearing spikes-2-the barren or stamenbearing spike-1.

calculated to afford a good general idea of the characters which distinguish the native wild flowers of our own land, and of the principles on which botanical distinctions are based.

Our next step must be to point out how the vegetable kingdom is mapped out by means of those

plant characters which have just engaged our atten

tion how it is divided

and subdivided, and its great leading classes marked off; how these again are resolved into tribes, families, and genera, so that the skilled botanist finding a plant he had never seen before, may, provided the plant has been enrolled with its brethren, as it were track it down, fix it in

class, in tribe, in family, till he finds it amid its

own kindred, associated

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with the other members of its own genus, and finally pounces upon it by the special mark of the individual.

THE ARRANGEMENT OR CLASSIFICATION OF PLANTS.

66 Happy who walks with Him! Whom what he finds

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WHEN we reflect that somewhere about eighty thousand different kinds or species of flowering plants are now known to botanists, and that, in addition to this large number, there exists an immense variety of vegetable productions which bear no flowers, we may well believe how hopeless would be the task of acquiring any definite or useful knowledge of the vegetable kingdom as a whole, unless its various component parts were reduced to some kind of arrangement or classification. Indeed, when not above a tenth part of the plants now known had been discovered, the necessity for some order amongst them was manifest, and the natural affinities which so obviously gather certain plants into tolerably well-defined groups began to engage the attention of the first cultivators of the science of botany.

Certain families of plants, such as the umbelbearers or hemlock-like tribes-Fig. 98-the labiates or mint-like tribe-Fig. 106-the grasses-Fig. 113 -present so strong a family resemblance one to the

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