On the Genesis of Species   By: St. George Jackson Mivart (1827-1900)

[Illustration]

ON THE

GENESIS OF SPECIES.

BY ST. GEORGE MIVART, F.R.S.

London: MACMILLAN AND CO. 1871.

[ The Right of Translation and Reproduction is reserved. ]

LONDON: R. CLAY, SONS, AND TAYLOR, PRINTERS, BREAD STREET HILL.

TO

SIR HENRY HOLLAND, BART., M.D.,

F.R.S., D.C.L., ETC. ETC.

MY DEAR SIR HENRY,

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.

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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