Insectivorous Plants

Insectivorous Plants

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Darwin (#23 in our series by Charles Darwin)
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Title: Insectivorous Plants
Author: Charles Darwin
Release Date: May, 2004 [EBook #5765] [Yes, we are more than one
year ahead of schedule] [This file was first posted on August 31, 2002]
Edition: 10

Language: English
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INSECTIVOROUS PLANTS ***

Project Gutenberg Etext of Insectivorous Plants by Charles Darwin.
Produced by Sue Asscher
[page i]

INSECTIVOROUS PLANTS.

[page ii.]

BY THE SAME AUTHOR.
---
ON THE ORIGIN OF SPECIES BY MEANS OF NATURAL
SELECTION; or, THE PRESERVATION OF FAVORED RACES IN
THE STRUGGLE FOR LIFE. New and revised edition. 12mo. Cloth.
480 pages. Price, $2.00.
THE DESCENT OF MAN, AND SELECTION IN RELATION TO
SEX. With Illustrations. New edition, revised and augmented. 12mo.
Cloth. 704 pages. Price, $3.00.
A NATURALIST'S VOYAGE ROUND THE WORLD; or, A
JOURNAL OF RESEARCHES INTO THE NATURAL HISTORY
AND GEOLOGY OF THE COUNTRIES visited during the voyage of
H.M.S. Beagle, under the command of Captain Fitz-Roy, R.N. 12mo.
Cloth. 530 pages. Price, $2.00.
THE EXPRESSION OF THE EMOTIONS IN MAN AND ANIMALS.
With Photographic and other Illustrations. 12mo. Cloth. Price, $3.00.
----
THE THEORY OF DESCENT, AND DARWINISM. By Prof.
OSCAR SCHMIDT, University of Strasburg. 12mo. Cloth. Price,
$1.50.
[page iii.]

INSECTIVOROUS PLANTS

BY CHARLES DARWIN, M.A., F.R.S. ETC.

WITH ILLUSTRATIONS.

[page iv.]
[page v.]

CONTENTS.

CHAPTER I.
DROSERA ROTUNDIFOLIA, OR THE COMMON SUN-DEW.
Number of insects captured--Description of the leaves and their
appendages or tentacles-- Preliminary sketch of the action of the
various parts, and of the manner in which insects are
captured--Duration of the inflection of the tentacles--Nature of the
secretion--Manner in which insects are carried to the centre of the
leaf--Evidence that the glands have the power of absorption--Small size
of the roots...Pages 1-18

CHAPTER II.
THE MOVEMENTS OF THE TENTACLES FROM THE CONTACT
OF SOLID BODIES.
Inflection of the exterior tentacles owing to the glands of the disc being
excited by repeated touches, or by objects left in contact with
them--Difference in the action of bodies yielding and not yielding
soluble nitrogenous matter--Inflection of the exterior tentacles directly
caused by objects left in contact with their glands--Periods of

commencing inflection and of subsequent re-expansion--Extreme
minuteness of the particles causing inflection--Action under
water--Inflection of the exterior tentacles when their glands are excited
by repeated touches--Falling drops of water do not cause
inflection...19-37 [page vi.]

CHAPTER III.
AGGREGATION OF THE PROTOPLASM WITHIN THE CELLS
OF THE TENTACLES.
Nature of the contents of the cells before aggregation--Various causes
which excite aggregation--The process commences within the glands
and travels down the tentacles-- Description of the aggregated masses
and of their spontaneous movements--Currents of protoplasm along the
walls of the cells--Action of carbonate of ammonia--The granules in the
protoplasm which flows along the walls coalesce with the central
masses--Minuteness of the quantity of carbonate of ammonia causing
aggregation--Action of other salts of ammonia--Of other substances,
organic fluids, &c.--Of water--Of heat--Redissolution of the aggregated
masses--Proximate causes of the aggregation of the
protoplasm--Summary and concluding remarks--Supplementary
observations on aggregation in the roots of plants...Pages 38-65

CHAPTER IV.
THE EFFECTS OF HEAT ON THE LEAVES.
Nature of the experiments--Effects of boiling water--Warm water
causes rapid inflection-- Water at a higher temperature does not cause
immediate inflection, but does not kill the leaves, as shown by their
subsequent re-expansion and by the aggregation of the protoplasm-- A
still higher temperature kills the leaves and coagulates the albuminous
contents of the glands...66-75

CHAPTER V.
THE EFFECTS OF NON-NITROGENOUS AND NITROGENOUS
ORGANIC FLUIDS ON THE LEAVES.
Non-nitrogenous fluids--Solutions of gum
arabic--Sugar--Starch--Diluted alcohol--Olive oil-- Infusion and
decoction of tea--Nitrogenous fluids--Milk--Urine--Liquid
albumen--Infusion of raw meat--Impure mucus--Saliva--Solution of
isinglass--Difference in the action of these two sets of
fluids--Decoction of green peas--Decoction and infusion of
cabbage--Decoction of grass leaves...76-84 [page vii.]

CHAPTER VI.
THE