Page:The Amateur's Greenhouse and Conservatory.djvu/244

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THE AMATEUR’S GREENHOUSE

as the pitchers increase in size the lid gradually rises, and then we may suppose it possible that water can find its way into the pitcher by means of condensed dew or the fall of rain. Not that water does find its way in; no! But water is almost always found there; it is secreted by the plant. If you dissect a pitcher, you will find that the epidermis, both within and without, is pierced with stomata, and the cellular tissue beneath is of a spongy texture, the cells large, and destitute of spiral vessels. Inside the pitcher are numerous hairs, which project downward; and it is found that when an insect enters, its downward course is easy, but escape is almost impossible; hence we not only find water, but also flies, wood-lice, and even beetles. Ah! the way to ruin is smooth and sometimes pleasant, and to go down is easier than to go up: so perhaps the flies find it in the pitchers, as we do also in the conduct of life. Water may be found in the pitchers long before the lid has been opened to catch it; and pitchers full grown are found with not a drop in them; indeed, you may find pitchers full that never were exposed to rain, and that were not filled by the syringing of the plants by the cultivator. To clear up the difficulty, we took some plants and kept one half of them plunged in pans of water, and the other half were kept as dry as possible so as not to kill them. What was the result? The plants that stood in water, had full pitchers; and the plants that were kept drier than they should be, had empty ones. It was reasonable to conclude therefrom that the plant has the power of storing up surplus water against the day of want, and that what we find is usually secreted, though that they should be filled by rain is, of course, possible. How could it be otherwise if rain happened to fall when the pitchers were open? As to the flies, they are, no doubt, attracted by the moisture, and perhaps a little sweetness. Put a jar of water in a house where there are crickets, and it will contain plenty of drowned crickets next morning. What, then, is the wonder that flies, finding the pitchers open, and smelling the moisture, should be tempted to their destruction? An English naturalist once supposed that the ichneumon fly would drag other flies, and hurl them over the edge of the pitcher to destruction, as a human murderer might throw a victim over a bridge. There is no mystery about the flies being there. Watch long enough, and you will see them go down, but however long you watch you will never see them return. The moral is too obvious.