Harmony and Conflict in the Living World - Alexander F. Skutch [53]
Hanging at the end of a tendril, the pitcher turns sharply upward, as is necessary to hold its liquid. It may be long and slender or short and stout, the latter especially in terrestrial pitchers, which may differ in shape from aerial pitchers of the same plant. The vessel narrows toward the oblique mouth, which is surrounded, as by a collar, by a firm, T-shaped, transversely corrugated rim, from which an array of sharp teeth project downward into the cavity. Above the mouth, on a necklike extension, stands a lid, which in some species is broad enough to serve as an umbrella
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Nepenthes edwardsiana, a tropical pitcher plant
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Nepenthes rajah, a tropical pitcher plant
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over the pitcher. Some pitchers are big: one from Borneo measured eighteen inches (46 cm.) in length, including the lid. Its capacious bowl was large enough to drown a small mammal or bird. Along the pitcher's front are two wings, often with fringed edges. These vessels attract attention by their bright colors, red, claret, cream, or green, spotted or mottled with crimson, purple, or violet. Nectar glands on the leaflike basal expansion and on the tendril at its apex lure ants and other creeping creatures onward to the pitcher at the tendril's end, where they find more such glands on the underside of the lid and between the teeth on the inner edge of the collar. If from this point they venture inward, they find themselves on a glaucous waxy surface, the conducting zone, from which they slip into the depths of the trap, where they are surrounded by walls that appear to be both digestive and absorptive.
Until well grown, the bowl is tightly covered by its lid. This is not fused to it by growth, but the joint is sealed by dense branching hairs, like the wad of cotton in the mouth of a test tube. The closed young pitcher holds much secreted water, neutral and devoid of bacteria. In this watery grave small victims are digested by proteolytic enzymes poured out by the glands. To what degree they are supplemented by bacterial action it is difficult to learn. From pitchers heavily loaded with prey, odors of putrefaction arise, but these overfed traps might be said to suffer from indigestion. In addition to multitudes of ants, the Nepenthes pitchers capture centipedes, cockroaches, butterflies, large scorpions, and doubtless much else.
Pitchers of Nepenthes have given refreshing drinks to thirsty travelers, sometimes saving their lives. Alfred Russel Wallace (1872), who explored the Malay Archipelago in the mid-nineteenth century, found these plants most abundant in Borneo, where they flourished on every mountaintop, running over the ground or clambering over shrubs and stunted trees. He repeatedly expressed his admiration for the elegant pitchers of these "wonderful" plants, some of which hold up to two quarts of water. He told how, while traversing a hot, open, rocky slope high on Mt. Ophir in Malacca, he and his porters were overcome with thirst. Finding nothing better, they at last turned to the pitchers of plants that grew from fis-
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West Australian pitcher plant, Cephalotus follicularis
sures of the rocks, but were at first repelled by the many insects floating in them. Thirst overcoming squeamishness, they tasted the liquid, finding it very palatable but rather warm. All quenched their thirst from these natural jugs.
Australia, which supports more than its due share of unusual plants and animals, is the home of a curious little pitcher plant confined to a small region in the extreme southwest of the island-continent. From a taproot growing in drier parts of peaty swamps, Cephalotus follicularis, the only species in a family named for itself, produces rosettes of two