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Show 340 DROSOPHYLLUM LUSITANICUM. CHAP. XV. completely liquefied, but with a few white streaks still visible; the other was much rounded, but not quite dissolved. Two other cu bos wore left on tall glands for 2 hrs. 45 m., by which time all the secretion was absorbed; but they were not perceptibly acted on, though no doubt some slight amount of ani1nal matter had been absorbed fi~om them. They were then placed on the small sessile glands, which being thus stimulated secreted copiously in the course of 7 hrs. One of these cubes was much liquefied within this short time; and both were completely liquefied after 21 hrs. 15 m.; the little liquid 1nasses, however, still showing some white streaks. ~rhese streaks d~sappeared after an additional period of 6 hrs. 30 1n. ; and by next morning (i. e. 48 hrs. from the time when the cubes were first placed on the glands) the liquefied matter was wholly absorbed. A cube of album en was left on another tall gland, which first absorbed the secretion and after 24 hrs. poured forth a fresh supply. This cube, now surrounded by secretion, was left on tho glanfl for an additional 24 hrs., but was very little, if at all, acted on. We may, therefore, conclud , either that the secretion from the tall glands has little power of digestion, though strongly acid, or that the amount poured forth from a single gland is insufficient to dissolve a particle of albumen which within the same time would have been dissolved by the secretion from several of the small sessile glands. Owing to the death of my last plant, I was unable to ascertain which of these alternatives is the true one. Four minute shreds of pure fibrin were placed, each resting on one, two, or three of the taller glands. In the course of 2 ~us. 30 m. the secretion was all absorbed, and the shreds were left almost dry. They CHAP. xv. CONCLUDING REMARKS. 341 were then pushed on to the sessile glands. One shred after 2 hrs. 30 .m., seemed quite dissolved, but this rna; have been a mistake. A second, when examined after 17 hrs. 25 ~., was liq~efied, but the liquid as seen under ~he microscope still contained floating granules of fibnn. The other two shreds were complete! liquefied after 21 hrs. 30 m.; but in one of the dro; a· very few gran~les could still be detected. These, however, were dissolved after an additional interval of 6 hrs. 30 m. ; and the surface of the leaf for some distance all round was covered with limpid fluid. It thus appears that Drosophyllum djo-ests albumen and fibrin rather more quickly thanb Drosera can. and this may perhaps be attributed to the acid' together probably with some small amount of th~ ferment, being present in the secretion, before the glands have been stimulated; so that digestion begins at once. Concluding Remarks .. -The linear leaves of Drosophy~ lum differ but slightly from those of certain species of Drosera ~ the chief differences being, firstly, t~e presence of minute, almost sessile, glands, which, hk~ those of Dionc.ea,. do not. secrete until they are excited by tl;le absorption of nitrogenous n1atter. But glands of this kind are present on the leaves of nro~era binata, and appear to be represented by the pap1llro on the leaves of Drosera rotundifolia. Secondly, the presence of tentacles on the backs of the leaves · but we h a:e seen t h at a £e w tentacles, irregularly placed' and tending towards abortion, are retained on the backs of the leaves of Drosera binata. There are gr~ater difference~ in function between the two ge~ nera. The most Important one is that the tentacles of Dro~ophyllum have no power of movement; this loss being partially replaced by· the drops of viscid |