Insectivorous plants . emarks. Experiment 1.—A young and almost upright leaf was selected,with its two lateral edges equally and very slightly row of small flies was placed along onemargin. When looked at next day, after15 hrs., this margin, but not the other, wasfound folded inwards, like the helix of thehuman ear, to the breadth of -^ of aninch, so as to lie partly over the row offlies (fig. 15). The glands on which theflies rested, as well as those on the over-lapping margin which had been broughtinto contact with the flies, were all secretingcopiously. Experiment 2.—A row of fli
Insectivorous plants . emarks. Experiment 1.—A young and almost upright leaf was selected,with its two lateral edges equally and very slightly row of small flies was placed along onemargin. When looked at next day, after15 hrs., this margin, but not the other, wasfound folded inwards, like the helix of thehuman ear, to the breadth of -^ of aninch, so as to lie partly over the row offlies (fig. 15). The glands on which theflies rested, as well as those on the over-lapping margin which had been broughtinto contact with the flies, were all secretingcopiously. Experiment 2.—A row of flies was placedon one margin of a rather old leaf, whichlay flat on the ground; and in this casethe margin, after the same interval as be-fore, namely 15 hrs., had only just begunto curl inwards; but so much secretionhad been poured forth that the spoon-shaped tip of the leaf was filled with it. Experiment 3.—Fragments of a large fly were placed close tothe apex of a vigorous leaf, as well as along half one Fig. 15, (Pinguicula vulgaris.) Outline of leaf with leftmargin inflected over arow of small flies. 372 PINGUICDLA VULGARIS. Chap. XVI. After 4 hrs. 20 m. there was decided incurvation, whicli in-creased a little during the afternoon, but was in the same stateon the following morning. Near the apex both margins wereinwardly curved. I have never seen a case of the apex itselfbeing in the least curved towards the base of the leaf. After48 hrs. (always reckoning from the time when the flies wereplaced on the leaf) the margin had everywhere begun to unfold. Experiment 4.—A large fragment of a fly was placed on a leaf,in a medial line, a little beneath the apex. Both lateral mar-gins were perceptibly incurved in 3 hrs., and after 4 hrs. 20 such a degiee that the fragment was clasped by both 24 hrs. the two infolded edges near the apex (for the lowerpart of the leaf was not at all affected) were measured andfound to be 11 of an inch (2-795 mm.) ap
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Keywords: ., bookcentury1800, bookdecade1870, bookpublishernewyo, bookyear1875
