The leaves and flowers of plants often grow into very strange shapes. The flowers of various kinds of orchids are very remarkable for the peculiar forms which they take. Some of them have a great resemblance to bees, flies, or butterflies, and this resemblance is at times so great that we wonder whether it is only an accidental likeness, or whether it serves some useful purpose. One of the oddest shapes which any plant takes, however, is that of the leaves of the pitcher-plant; and in this case naturalists, who have studied the plant carefully, are able to show us that the strange shape of the leaf really serves a purpose.

The pitcher-plants are most abundant in the islands of Borneo, Java, and Sumatra, and in the Malay Peninsula. Though not so plentiful elsewhere, they are also found in Ceylon, Madagascar, the Moluccas, and one or two other places. The plant is a kind of creeping or climbing shrub which runs along the ground, or climbs up other shrubs and short trees. It seems to thrive best upon the mountaintops, and the summits of the mountains of Borneo are often gaily decked with it.

There are thirty or forty different kinds of pitcher-plants, varying in size a great deal. But the strange thing about all of them is that the ends of their leaves are shaped like pitchers, or perhaps it would describe them better if we said they were like jugs with lids. It is from this peculiarity that the plant takes its name. The leaf is the shape of any ordinary leaf until it reaches its point, where it is drawn out into a long stalk or tendril, at the end of which is the jug or pitcher, which, you must remember, is formed out of the leaf itself. Each plant has its own shape of jug, and the jugs vary in size a good deal. Some are long and slender; others are broad and shallow. Some are tiny jugs only an inch deep, while others are perhaps twenty inches deep. Their colour is green, but the mouth of the jug and the under side of the lid, which is always open, are spotted with red or purple, somewhat like a flower.

Not only do these strange leaves look like jugs, but they are also used as jugs. Each of them contains a little supply of water, varying with the size of the jug from a few drops in the smallest, to as much as two quarts in the largest of them. Thirsty travellers have sometimes quenched their thirst from these natural jugs, when no other water was to be found. Though the water itself is palatable, it is a little warm, and it is always full of insects.

If any one were to watch one of these jugs of the pitcher-plant for some time attentively, he would soon find that it served as a trap for flies and insects. One by one the little creatures alight upon the outside of the jug, and creep into the open mouth, and few or none of them ever return. They slip into the water at the bottom of the jug and are drowned.

If we examine a jug carefully, in order to learn why the insects enter it, and how it is that they cannot get out again, we shall be surprised at the clever way in which the trap is made. The mouth of the jug has a thick ring round it, which makes it firm, and keeps it always open. The lid stands over this mouth, and seems to be always raised a good deal, so that insects and flies may enter freely; but it covers the mouth in such a way as to prevent anything from falling accidentally into the jug from above. The underside of the lid and the mouth of the jug are often gaily coloured, so as to attract insects, as brightly-coloured flowers do. Some of the jugs even make a little honey, which, forming just inside the mouth, attracts insects by its scent. Within the jug, just below the mouth, there is a row of stiff hooks, which have their points turned inwards towards the bottom of the jug. Below the spikes the sides of the jug are so smooth and slippery that few insects could stand on them.

It is easy to see how the trap works. Insects are attracted to the pitcher by the bright colours of the lid or the scent of the honey. They creep into the mouth, and crawl between the hooks, whose sharp points are set the other way, and they step upon the smooth and slippery inside of the jug. In another instant they have slipped into the water at the bottom of the jug. Do what they will, they cannot climb up the slippery sides of the pitcher, or pass the row of sharp hooks, whose points are turned against them. They are caught.

Now all this is very strange and wonderful, and it makes us wish to know why Providence has given the plant this clever machinery. We cannot help asking ourselves why the pitcher-plant entraps these insects. I am afraid that you would hardly be able to answer this question for yourself, however carefully you might watch a pitcher-plant. Indeed, it is only a few years since clever men, making careful experiments, were able to find out the real truth. The fluid at the bottom of the pitcher digests those insects, and the pitcher-plant feeds upon them. Just as the juices of our stomach dissolve meat, so that it may pass into the blood and nourish us, so the fluid in the jug of the pitcher-plant dissolves the flesh of the insects which fall into it, and makes that flesh fit to nourish the plant. This strange plant lives, in part at least, upon flesh; and all the clever mechanism of its jug is used simply to get a meal.