The Origin of Species by means of Natural Selection (6th ed) | Page 8

from the extinct by new
creations, but are to be regarded as their descendants through continued
reproduction."
A well-known French botanist, M. Lecoq, writes in 1854 ("Etudes sur
Geograph. Bot. tom. i, page 250), "On voit que nos recherches sur la
fixite ou la variation de l'espece, nous conduisent directement aux idees
emises par deux hommes justement celebres, Geoffroy Saint-Hilaire et
Goethe." Some other passages scattered through M. Lecoq's large work
make it a little doubtful how far he extends his views on the
modification of species.
The "Philosophy of Creation" has been treated in a masterly manner by
the Rev. Baden Powell, in his "Essays on the Unity of Worlds", 1855.
Nothing can be more striking than the manner in which he shows that
the introduction of new species is "a regular, not a casual
phenomenon," or, as Sir John Herschel expresses it, "a natural in
contradistinction to a miraculous process."
The third volume of the "Journal of the Linnean Society" contains
papers, read July 1, 1858, by Mr. Wallace and myself, in which, as
stated in the introductory remarks to this volume, the theory of Natural
Selection is promulgated by Mr. Wallace with admirable force and
clearness.
Von Baer, toward whom all zoologists feel so profound a respect,

expressed about the year 1859 (see Prof. Rudolph Wagner,
"Zoologisch-Anthropologische Untersuchungen", 1861, s. 51) his
conviction, chiefly grounded on the laws of geographical distribution,
that forms now perfectly distinct have descended from a single
parent-form.
In June, 1859, Professor Huxley gave a lecture before the Royal
Institution on the "Persistent Types of Animal Life". Referring to such
cases, he remarks, "It is difficult to comprehend the meaning of such
facts as these, if we suppose that each species of animal and plant, or
each great type of organisation, was formed and placed upon the
surface of the globe at long intervals by a distinct act of creative power;
and it is well to recollect that such an assumption is as unsupported by
tradition or revelation as it is opposed to the general analogy of nature.
If, on the other hand, we view "Persistent Types" in relation to that
hypothesis which supposes the species living at any time to be the
result of the gradual modification of pre-existing species, a hypothesis
which, though unproven, and sadly damaged by some of its supporters,
is yet the only one to which physiology lends any countenance; their
existence would seem to show that the amount of modification which
living beings have undergone during geological time is but very small
in relation to the whole series of changes which they have suffered."
In December, 1859, Dr. Hooker published his "Introduction to the
Australian Flora". In the first part of this great work he admits the truth
of the descent and modification of species, and supports this doctrine
by many original observations.
The first edition of this work was published on November 24, 1859,
and the second edition on January 7, 1860.

CONTENTS.
INTRODUCTION

CHAPTER I.
VARIATION UNDER DOMESTICATION.
Causes of Variability -- Effects of Habit and the use or disuse of Parts
-- Correlated Variation -- Inheritance -- Character of Domestic
Varieties -- Difficulty of distinguishing between Varieties and Species
-- Origin of Domestic Varieties from one or more Species -- Domestic
Pigeons, their Differences and Origin -- Principles of Selection,
anciently followed, their Effects -- Methodical and Unconscious
Selection -- Unknown Origin of our Domestic Productions --
Circumstances favourable to Man's power of Selection.


CHAPTER II.
VARIATION UNDER NATURE.
Variability -- Individual Differences -- Doubtful species -- Wide
ranging, much diffused, and common species, vary most -- Species of
the larger genera in each country vary more frequently than the species
of the smaller genera -- Many of the species of the larger genera
resemble varieties in being very closely, but unequally, related to each
other, and in having restricted ranges.


CHAPTER III.
STRUGGLE FOR EXISTENCE.

Its bearing on natural selection -- The term used in a wide sense --
Geometrical ratio of increase -- Rapid increase of naturalised animals
and plants -- Nature of the checks to increase -- Competition universal
-- Effects of climate -- Protection from the number of individuals --
Complex relations of all animals and plants throughout nature --
Struggle for life most severe between individuals and varieties of the
same species; often severe between species of the same genus -- The
relation of organism to organism the most important of all relations.


CHAPTER IV.
NATURAL SELECTION; OR THE SURVIVAL OF THE FITTEST.
Natural Selection -- its power compared with man's selection -- its
power on characters of trifling importance -- its power at all ages and
on both sexes -- Sexual Selection -- On the generality of intercrosses
between individuals of the same species