On the Genesis of Species

In giving myself the pleasure to dedicate, as I now do, this work to you, it is not my intention to identify you with any views of my own advocated in it.

I simply avail myself of an opportunity of paying a tribute of esteem and regard to my earliest scientific friend--the first to encourage me in pursuing the study of nature.

I remain, MY DEAR SIR HENRY, Ever faithfully yours, ST. GEORGE MIVART.

7, NORTH BANK, REGENT'S PARK, December 8, 1870.

{vii} * * * * *

CONTENTS.

CHAPTER I.

INTRODUCTORY

The problem of the genesis of species stated.--Nature of its probable solution.--Importance of the question.--Position here defended.--Statement of the DARWINIAN THEORY.--Its applicability to details of geographical distribution; to rudimentary structures; to homology; to mimicry, &c.--Consequent utility of the theory.--Its wide acceptance.--Reasons for this other than, and in addition to, its scientific value. Its simplicity.--Its bearing on religious questions.--Odium theologicum and odium antitheologicum.--The antagonism supposed by many to exist between it and theology neither necessary nor universal.--Christian authorities in favour of evolution.--Mr. Darwin's "Animals and Plants under Domestication."--Difficulties of the Darwinian theory enumerated ... Page 1

CHAPTER II.

THE INCOMPETENCY OF "NATURAL SELECTION" TO ACCOUNT FOR THE INCIPIENT STAGES OF USEFUL STRUCTURES.

Mr. Darwin supposes that Natural-Selection acts by slight variations.--These must be useful at once.--Difficulties as to the giraffe; as to mimicry; as to the heads of flat-fishes; as to the origin and constancy of the vertebrate, limbs; as to whalebone; as to the young kangaroo; as to sea-urchins; as to certain processes of {viii} metamorphosis; as to the mammary gland; as to certain ape characters; as to the rattlesnake and cobra; as to the process of formation of the eye and ear; as to the fully developed condition of the eye and ear; as to the voice; as to shell-fish; as to orchids; as to ants.--The necessity for the simultaneous modification of many individuals.--Summary and conclusion ... Page 23

CHAPTER III.

THE CO-EXISTENCE OF CLOSELY SIMILAR STRUCTURES OF DIVERSE ORIGIN.

Chances against concordant variations.--Examples of discordant ones.--Concordant variations not unlikely on a non-Darwinian evolutionary hypothesis.--Placental and implacental mammals.--Birds and reptiles.--Independent origins of similar sense organs.--The ear.--The eye.--Other coincidences.--Causes besides Natural Selection produce concordant variations in certain geographical regions.--Causes besides Natural Selection produce concordant variations in certain zoological and botanical groups.--There are homologous parts not genetically related.--Harmony in respect of the organic and inorganic worlds.--Summary and conclusion ... Page 63

CHAPTER IV.

MINUTE AND GRADUAL MODIFICATIONS.

There are difficulties as to minute modifications, even if not fortuitous.--Examples of sudden and considerable modifications of different kinds.--Professor Owen's view.--Mr. Wallace.--Professor Huxley.--Objections to sudden changes.--Labyrinthodont.--Potto.--Cetacea.--As to origin of bird's wing.--Tendrils of climbing plants.--Animals once supposed to be connecting links.--Early specialization of structure.--Macrauchenia.--Glyptodon.--Sabre-toothed tiger.--Conclusion ... Page 97

{ix} CHAPTER V.

AS TO SPECIFIC STABILITY.

What is meant by the phrase "specific stability;" such stability to be expected a priori, or else considerable changes at once.--Rapidly increasing difficulty of intensifying race characters; alleged causes of this phenomenon; probably an internal cause co-operates.--A certain definiteness in variations.--Mr. Darwin admits the principle of specific stability in certain cases of unequal variability.--The goose.--The peacock.--The guinea fowl.--Exceptional causes of variation under domestication.--Alleged tendency to reversion.--Instances.--Sterility of hybrids.--Prepotency of pollen of same species, but of different race.--Mortality in young gallinaceous hybrids.--A bar to intermixture exists somewhere.--Guinea-pigs.--Summary and conclusion ... Page 113