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the bristles will close upon it in the same manner; but to a particle of chalk or wood they remain nearly indifferent. If any doubt should still remain whether the fly-catching in Sundews is accidental or intentional,-in other words, whether the leaf is so constructed and arranged in order that it may capture flies--the doubt may perhaps disappear upon the contemplation of another and even more extraordinary plant of the same family as the Sundew, namely, Venus's Flytrap or Dionæa muscipula. This plant abounds in some parts of North Carolina, and is native nowhere else. It is not very difficult to cultivate, at least for a time, and it is kept in many choice conservatories as a vegetable wonder.
8. The trap is the end of the leaf. It is somewhat like the leaf of the Sundew, only larger, about an inch in diameter, with bristles still stouter but only round the margin like a fringe, and with no clammy liquid or gland at their tips. The leaf folds on itself as if hinged at the midrib. Three more delicate bristles are seen on the face upon close inspection. When these are touched by the finger or the point of a pencil, the open trap shuts with a quick motion, and after a considerable interval it reopens. When a fly or other insect alights on the surface and brushes against these sensitive bristles, the trap closes promptly, generally imprisoning the intruder. It closes at first with the sides convex and the bristles crossing each other like the fingers of interlocked hands or the teeth of a steel trap. But soon the sides of the trap flatten down and press firmly upon the victim; and it now requires a very considerable force to open the trap. nothing is caught, the trap presently reopens of itself and is ready for another attempt. When a fly or any similar insect is captured, it is retained until it perishes,-is killed indeed and consumed; after which the leaf opens for another capture. But after the first or second it acts sluggishly and feebly, it ages and hardens, at length loses its sensibility, and slowly decays.
9. It cannot be supposed that plants, like boys, catch flies for pastime or in objectless wantonness. Living beings though they are, yet they are not of a sufficiently high order for that. It is equally incredible that such an exquisite apparatus as this should be purposeless. And in the present case the evidence of the purpose and of the meaning of the strange action is well-nigh complete. The face of this living trap is thickly sprinkled with glands immersed in its texture of elaborate structure under the microscope, but large enough to be clearly discerned with a hand lens. These glands, soon after an insect is closed upon, give out a saliva-like liquid, which moistens the insect and in a short time (within a week) dissolves all its soft parts,—digests them, we must believe; and the liquid, with the animal matter it has dissolved, is reabsorbed into the leaf. We are forced to conclude that, in addition to the ordinary faculties and functions of a vegetable, this plant is really carnivorous.
10. That, while all plants are food for animals, some few should in turn and to some extent feed upon them, will appear more credible when it is considered that the whole tribe of plants of the lowest grade (Mould-Fungi, and the like) habitually feed upon living plants and living animals, or upon their juices when dead. An account of them would make a volume of itself and an interesting one. But all goes to show that these extraordinary proceedings are not mere prodigies, wholly out of the general order of nature, but belong to the order of nature, and indeed are hardly different in kind from, or really more wonderful than, the doings of many of the commonest plants, which, until our special attention is called to them, ordinarily pass unregarded. —Slightly altered from “ How Plants Behave,” by Professor Asa Gray (b. 1810).
Questions on the lesson :—How do plants usually behave towards insects? How is the capture of insects sometimes to be explained ? What example is given? What different parts of the plant serve as the trap? What is the pitcher of the plant of that name? What is found in it? Why are the insects unable to escape? From what circumstance does the Sundew receive its name? How is it fitted for catching flies? How does the Round-leaved Sundew act when raw meat is placed on the leaves? When chalk or wood? Where is Venus's Flytrap found? How is it treated? What forms the trap? How does it differ from the Sundew? How is the leaf able to bend over on any object? What causes it to bend? If nothing is caught how does it act? If a victim is inclosed what occurs? What use does the plant make of the captured insects? What is the leaf covered with? What issues from these glands? What other examples are mentioned of plants living on animals and also on other plants?
1. The western waves of ebbing day
Rolled o'er the glen their level way;
2. The rocky summits, split and rent,
Formed turret, dome, or battlement
of Eastern architect,
Waved in the west wind's summer sighs. 3. Boon nature scattered, free and wild,
Each plant or flower, the mountain's child.
With boughs that quaked at every breath. 4. Grey birch and aspen wept beneath;
Aloft, the ash and warrior oak
The scenery of a fairy dream.
A narrow inlet, still and deep,
Still broader sweep its channels made. 6. The shaggy mounds no longer stood,
Emerging from entangled wood,
An islet in an inland sea.
No pathway meets the wanderer's ken,