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This eBook from the Gutenberg Project consists of approximately 462 pages of information about Insectivorous Plants.

[(1) A moderately sized and angular bit of albumen was placed on one side of a leaf, halfway between the midrib and the naturally involuted margin.  In 2 hrs. 15 m. the glands poured forth much secretion, and this side became more infolded than the opposite one.  The inflection increased, and in 3 hrs. 30 m. extended up almost to the apex.  After 24 hrs. the margin was rolled into a cylinder, the outer surface of which touched the blade of the leaf and reached to within the 1/20 of an inch of the midrib.  After 48 hrs. it began to unfold, and in 72 hrs. was completely unfolded.  The cube was rounded and greatly reduced in size; the remainder being in a semi-liquefied state.

(2) A moderately sized bit of albumen was placed near the apex of a leaf, under the naturally incurved margin.  In 2 hrs. 30 m. much secretion was excited, and next morning the margin on this side was more incurved than the opposite one, but not to so great a degree as in the last case.  The margin unfolded at the same rate as before.  A large proportion of the albumen was dissolved, a remnant being still left.

(3) Large bits of albumen were laid in a row on the midribs of two leaves, but produced in the course of 24 hrs. no effect; [page 393] nor could this have been expected, for even had glands existed here, the long bristles would have prevented the albumen from coming in contact with them.  On both leaves the bits were now pushed close to one margin, and in 3 hrs. 30 m. this became so greatly inflected that the outer surface touched the blade; the opposite margin not being in the least affected.  After three days the margins of both leaves with the albumen were still as much inflected as ever, and the glands were still secreting copiously.  With Pinguicula vulgaris I have never seen inflection lasting so long.

(4) Two cabbage seeds, after being soaked for an hour in water, were placed near the margin of a leaf, and caused in 3 hrs. 20 m. increased secretion and incurvation.  After 24 hrs. the leaf was partially unfolded, but the glands were still secreting freely.  These began to dry in 48 hrs., and after 72 hrs. were almost dry.  The two seeds were then placed on damp sand under favourable conditions for growth; but they never germinated, and after a time were found rotten.  They had no doubt been killed by the secretion.

(5) Small bits of a spinach leaf caused in 1 hr. 20 m. increased secretion; and after 3 hrs. 20 m. plain incurvation of the margin.  The margin was well inflected after 9 hrs. 15 m., but after 24 hrs. was almost fully re-expanded.  The glands in contact with the spinach became dry in 72 hrs.  Bits of albumen had been placed the day before on the opposite margin of this same leaf, as well as on that of a leaf with cabbage seeds, and these margins remained closely inflected for 72 hrs., showing how much more enduring is the effect of albumen than of spinach leaves or cabbage seeds .

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