Not a vestige of the albumen or gelatine was left. Similarly sized pieces were placed at the same time on wet moss on the same pot, so that they were subjected to nearly similar conditions; after eight days these were brown, decayed, and matted with fibres of mould, but had not disappeared.

Experiment 3.--A piece of albumen 3/20 of an inch (3.81 mm.) long, and 1/20 broad and thick, and a piece of gelatine of the same size as before, were placed on another leaf, which was cut open after seven days; not a vestige of either substance was left, and only a moderate amount of secretion on the surface.

Experiment 4.--Pieces of albumen and gelatine, of the same size as in the last experiment, were placed on a leaf, which spontaneously opened after twelve days, and here again not a vestige of either was left, and only a little secretion at one end of the midrib.

Experiment 5.--Pieces of albumen and gelatine of the same size were placed on another leaf, which after twelve days was still firmly closed, but had begun to wither; it was cut open, and contained nothing except a vestige of brown matter where the albumen had lain.

Experiment 6.--A cube of albumen of 1/10 of an inch and a piece of gelatine of the same size as before were placed on a leaf, which opened spontaneously after thirteen days, The albumen, which was twice as thick as in the latter experiments, was too large; for the glands in contact with it were injured and were dropping off; a film also of albumen of a brown colour, matted with mould, was left. All the gelatine was absorbed, and there was only a little acid secretion left on the midrib.

Experiment 7.--A bit of half roasted meat (not measured) and a bit of gelatine were placed on the two ends of a leaf, which [page 303] opened spontaneously after eleven days; a vestige of the meat was left, and the surface of the leaf was here blackened; the gelatine had all disappeared.

Experiment 8.--A bit of half roasted meat (not measured) was placed on a leaf which was forcibly kept open by a clip, so that it was moistened with the secretion (very acid) only on its lower surface. Nevertheless, after only 22 1/2 hrs. it was surprisingly softened, when compared with another bit of the same meat which had been kept damp.

Experiment 9.--A cube of 1/10 of an inch of very compact roasted beef was placed on a leaf, which opened spontaneously after twelve days; so much feebly acid secretion was left on the leaf that it trickled off. The meat was completely disintegrated, but not all dissolved; there was no mould. The little mass was placed under the microscope; some of the fibrillae in the middle still exhibited transverse striae; others showed not a vestige of striae; and every gradation could be traced between these two states. Globules, apparently of fat, and some undigested fibro-elastic tissue remained. The meat was thus in the same state as that formerly described, which was half digested by Drosera. Here, again, as in the case of albumen, the digestive process seems slower than in Drosera. At the opposite end of the same leaf, a firmly compressed pellet of bread had been placed; this was completely disintegrated, I suppose, owing to the digestion of the gluten, but seemed very little reduced in bulk.

Experiment 10.--A cube of 1/20 of an inch of cheese and another of albumen were placed at opposite ends of the same leaf. After nine days the lobes opened spontaneously a little at the end enclosing the cheese, but hardly any or none was dissolved, though it was softened and surrounded by secretion. Two days subsequently the end with the albumen also opened spontaneously (i.e. eleven days after it was put on), a mere trace in a blackened and dry condition being left.

Experiment 11.--The same experiment with cheese and albumen repeated on another and rather torpid leaf. The lobes at the end with the cheese, after an interval of six days, opened spontaneously a little; the cube of cheese was much softened, but not dissolved, and but little, if at all, reduced in size.

Charles Darwin

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