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Inorganic bodies, even of large size, such as bits of stone, glass and such like, or organic bodies not containing nitrogeneous matter in a soluble condition, as bits of cork, wood, moss for examples, or bodies containing soluble nitrogeneous matter, if perfectly dry, such as small pieces of meat, albumen, gelatine, etc., may be long left on the lobes, and no movement is excited. But when nitrogeneous organic bodies, which are all damp, are left on the lobes, the result is widely different, for these then close by a slow and gradual movement and not in a rapid manner as when one of the sensitive filaments is touched by a hard substance. Small purplish, almost sessile glands, as has already been stated, thickly cover the upper surface of the lobes. These have the power both of secretion and absorption, but they do not secrete until excited by the absorption of nitrogeneous matter. No other excitement, as far as experiments show, produces this effect. When the lobes are made to close over a bit of meat or an insect, the glands over the entire surface of the leaf emit a copious discharge, as in this case the glands on both sides are pressed against the meat or insect, the secretion being twice as great as when the one or the other is laid on the surface of a single lobe; and as the two lobes come into almost close contact the secretion, containing dissolved animal matter, diffuses itself by capillary attraction, causing fresh glands on both sides to begin secreting in a continually widening circle. The secretion is almost colorless, slightly mucilaginous, moderately acid, and so copious at times in the furrow over the mid-rib as to trickle down to the earth. But all this secretion is for the purposes of digestion. Be the animal matter which the enclosed object yields ever so little, it serves as a peptogene, and the glands on the surface of the leaf pour forth their acid discharge, which acts like the gastric juice of animals.

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