Imatges de pàgina
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moment, leaving his companion in amused wonderment as to what new "weed" his friend is by this time so busy gathering. Our botanist had been expatiating to his companion all morning upon the beauty of the grass of Parnassus (Parnassia palustris) of our hills, and now he returns with his hands full of the blossoms, ready, as soon as he regains breath, to point out its perfections, not forgetting to remark upon the apparently instinctive movements of its stamens as they fulfil their office of fertilization. We will not follow our botanist on his walk, his ups and downs, his jump over the hedge for a specimen of the brilliant hemp-nettle, or his plunge up to the knees in water to pluck the flowering rush or the arrow-head: but we will ask our reader whether a walk, thus enlivened with ever-recurring sources of interest, is not a pleasant one. It is a regular sporting tour, full of excitement, and its game,

"Each plant or flower the mountain's child."

FLOWER-BUDS AND FLORAL
METAMORPHOSIS.

"There's not a blossom fondled by the breeze,
There's not a fruit that beautifies the trees,
There's not a particle in sea or air,

But nature owns thy plastic influence there."
R. MONTGOMERY.

WE have already remarked that in the leaf-bud the contents are always arranged in a certain definite manner in different plants: a parallel arrangement, known to botanists as the æstivation, do we find in the flower-bud. The calyx varies in its bud arrangements, but the corolla still more So. In some plants, as the wood-sorrel, the gentians, or the mallow, it is spirally twisted; in others, as the convolvulus, it is plaited; in the campanula it is valve-like, in the geraniums overlapping, in the poppy crumpled. These things we doubt not many of our readers must have marked for themselves, and will doubtless mark still more attentively, now that their attention has been directed towards them; but, to most, probably, the subject which gives the second heading to this short chapter is new, and they are ready to ask what is meant by floral metamorphosis.

Did you ever, reader, gather a polyanthus or primrose, with, as it were, one flower growing out of another, or with the calyx showing a tendency to imitate the form of the ordinary leaves of the plant? Or did you ever see and wonder at a full-blown rose,

F

having an ill-formed bud growing out of its centre? Or did you ever examine a rose blossom or a tulip becoming double, or the flower of the beautiful white water-lily, and find some of the stamens, as it were, half petal and half stamen? If you have observed any of these, you will more readily understand the nature of floral metamorphosis, and admit the idea that every part of the flower is but a modification of the ordinary leaf; or, in other words, that every blossom is but a bunch, or more properly a series, of transformed leaves arranged in a certain regular order. This may seem to some persons, at first, a very far-fetched and gratuitous doctrine; but, nevertheless, it is one, the truth of which is well borne out by the observations of botanists in the case of plant structure generally, but especially so by the occasional monstrosities, as they are called, which show attempts to return the flower partly or entirely to the form of the original leaf. The annexed figures, which represent on an enlarged scale some florets of a head of common Dutch clover-which is peculiarly liable to this form of monstrosity-afford an instance sufficiently illustrative of the fact. At Fig. 64, 1, we see the legume or pod alone, imperfectly formed, and partaking of the leaf character, which is completely assumed in the floret-Fig. 65, In Fig. 66 the trefoil character is more completely displayed, the centre leaflet bearing on its margins two or three minute leaflets-2-which evidently correspond to seeds. At Fig. 67 we have again the imperfectly developed pod, and some of the calyx segments tending to assume the trefoil. Fig 68 shows the imperfect pod

of Fig. 67 laid open to display the seeds.

Thus we

find that calyx, corolla, stamens, and pistils, are all but modifications of the simple leaf, and that even

64. Floret of common Dutch clover, showing legume or pod-1-but half formed (magnified).

a

65. Floret of Dutch clover, showing leaflet-1- occupying the place of the pod.

66. Floret of Dutch clover, showing trefoil leaf-1occupying the place of the pod; the centre leaflet bearing on its margins two or three minute leaflets-2 -evidently corresponding to seeds.

the seeds themselves may be regarded in a similar light-Fig. 66, 2,-the carpel or seed-vessel of the

pistil being simply a folded leaf joined at

the margins, and bearing at these margins the seed.

The subject of floral metamorphosis we have just lightly touched upon is full of interest for its own sake; worthier

67. Floret of Dutch

clover, showing half-
part of the flower de-

developed pod -1

veloped-2-and the

still is it of attention calyx-3-tending to

as a beautiful exempli

become leaf-like.

68. The half

developed pod of Fig. 67 laid open to show seeds.

fication of the simple principles which form the foundations of His works from whom both works

and principles alike derive their origin.

ARRANGEMENT OF BLOSSOMS.

INFLORESCENCE.

HAVING examined the various parts of the plant and of the blossom, our readers might imagine that with this our remarks on descriptive botany should cease; but there yet remains for us that most important subject, the form of flower development, and the arrangement, so to speak, of the blossoms upon the plant; the inflorescence, as botanists designate it. Many different circumstances are there, as we have already seen, contributing to give that charming and never-ending variety which extends over the whole of the vegetable creation, but none perhaps adds more largely to that variety than the differences in the modes of inflorescence.

Most blossoms, or collections of blossoms, are supported upon a primary stalk or flower-stem, named the peduncle Figs. 69, 71, &c. In some cases, the flower or flowers are directly borne by the peduncle, but very frequently this main stem gives off other little stems, as in the currant, cowslip, &c.-Figs. 69, 71, 72, &c., and then these little stems are named the pedicels. Many plants, like the primrose, the dandelion, &c., send the flower-stalk, as it were, direct from the ground; it is a simple stem, bearing the flower alone, but neither leaf nor branch, and is then further distinguished as the scape-Fig. 69.

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