f*" T,

CONTRIBUTIONS TO

THE THEORY OF

NATURAL SELECTION.

juries of

BY

ALFEED EUSSEL WALLACE,

AUTHOR OF
" THE MALAY ARCHIPELAGO," ETC., ETC.

M- AC HIIi LAN AND CO.,

ILontion,

AND 63, BLEEKER STEEET,

1870.

[The right oj Translation and Reproduction is reserctd.]

LONDON :

PRINTED BY W. W. HEAD, ROYAL VICTORIA PRESS,
FARRINGDON STREET, E.C.

PREFACE.

THE present volume consists of essays which I have
contributed to various periodicals, or read before scien-
tific societies during the last fifteen years, with others
now printed for the first time. The two first of the-
series are printed without alteration, because, having
gained me the reputation of being an independent
originator of the theory of " natural selection," they
may be considered to have some historical value. I
have added to them one or two very short explanatory
notes, and have given headings to subjects, to make
them uniform with the rest of the book. The other
essays have been carefully corrected, often consider-
ably enlarged, and in some cases almost rewritten, se-
as to express more fully and more clearly the views
which I hold at the present time ; and as most of
them originally appeared in publications which have-
a very limited circulation, I believe that the larger
portion of this volume will be new to many of my
friends and to most of my readers.

I now wish to say a few words on the reasons which
have led me to publish this work. The second essay,
especially when taken in connection with the first,
contains an outline sketch of the theory of the origin
of species (by means of what was afterwards termed
by Mr. Darwin — "natural selection,") as conceived

IV Pit EF ACE.

by me before I had the least notion of the scope and
nature of Mr. Darwin's labours. They were published
in a way not likely to attract the attention of any but
working naturalists, and I feel sure that many who
have heard of them, have never had the opportunity
of ascertaining how much or how little they really con-
tain. It therefore happens, that, while some writers
give me more credit than I deserve, others may very
naturally class me with Dr. Wells and Mr. Patrick
Matthew, who, as Mr. Darwin has shown in the his-
torical sketch given in the 4th and 5th Editions of
the " Origin of Species," certainly propounded the
fundamental principle of " natural selection " before
himself, but who made no further use of that principle,
and failed to see its wide and immensely important
applications.

The present work will, I venture to think, prove,
that I both saw at the time the value and scope of
the law which I had discovered, and have since been
able to apply it to some purpose in a few original
lines of investigation. But here my claims cease.
I have felt all my life, and I still feel, the most
sincere satisfaction that Mr. Darwin had been at
work lon£ before me, and that it was not left for me

tD 7

to attempt to write " The Origin of Species." I have
long since measured my own strength, and know well
that it would be quite unequal to that task. Far
abler men than myself may confess, that they have
not that untiring patience in accumulating, and that
wonderful skill in using, large masses of facts of the

PREFACE. y

most varied kind, — that wide and accurate physio-
logical knowledge, — that acuteness in devising and
skill in carrying out experiments, — and that admirable
style of composition, at once clear, persuasive and
judicial, — qualities, which in their harmonious combi-
nation mark out Mr. Darwin as the man, perhaps of
all men now living, best fitted for the great work he
has undertaken and accomplished.

My own more limited powers have, it is true, enabled
me now and then to seize on some conspicuous group
of unappropriated facts, and to search out some gene-
ralization which might bring them under the reign
of known law ; but they are not suited to that more
scientific and more laborious process of elaborate in-
duction, which in Mr. Darwin's hands has led to such
brilliant results.

Another reason which has led me to publish this
volume at the present time is, that there are some im-
portant points on which I differ from Mr. Darwin, and
I wish to put my opinions on record in an easily
accessible form, before the publication of his new
work, (already announced,) in which I believe most
of these disputed questions will be fully discussed.

I will now give the date and mode of publication of
each of the essays in this volume, as well as the amount
of alteration they have undergone.

I. — ON THE LAW WHICH HAS REGULATED THE INTRO-
DUCTION OF NEW SPECIES.

First published in the " Annals and Magazine of

VI PREFACE.

Natural History," September, 1855. Reprinted with-
out alteration of the text.

II. — ON THE TENDENCY OF VARIETIES TO DEPART

INDEFINITELY FROM THE ORIGINAL TYPE.

First published in the " Journal of the Proceedings
of the Linnsean Society," August, 1858. Reprinted
without alteration of the text, except one or two
grammatical emendations.

III. — MIMICRY AND OTHER PROTECTIVE RESEMBLANCES
AMONG ANIMALS.

First published in the a Westminster Review," July,
1867. Reprinted with a few corrections and some
important additions, among which I may especially
mention Mr. Jenner Weir's observations and experi-
ments on the colours of the caterpillars eaten or
rejected by birds.

IV. — THE MALAYAN PAPILIONID^E, OR SWALLOW-
TAILED BUTTERFLIES, AS ILLUSTRATIVE OF THE
THEORY OF NATURAL SELECTION.

First published in the " Transactions of the Lin-
nsean Society," Vol. XXV. (read March, 1864), under
the title, " On the Phenomena of Variation and Geo-
graphical Distribution, as illustrated by the Papilionidas
of the Malayan Region."

The introductory part of this essay is now reprinted,
omitting tables, references to plates, &c., with some ad-
ditions, and several corrections. Owing to the publi-

Fit EF ACE. Vll

cation of Dr. Felder's " Voyage of tlie Novara" (Lepi-
doptera) in the interval between the reading of my
paper and its publication, several of my new species
must have their names changed for those given to
them by Dr. Felder, and this will explain the want of
agreement in some cases between the names used
in this volume and those of the original paper.

V. — ON INSTINCT IN MAN AND ANIMALS.
Not previously published.

VI. — THE PHILOSOPHY OF BIRDS' NESTS.

First published in the " Intellectual Observer," July,
1867. Keprinted with considerable emendations and
additions.

VII. — A THEORY OF BIRDS' NESTS ;

SHOWING THE RELATION OF CERTAIN DIFFERENCES OF
COLOUR IN BIRDS TO THEIR MODE OF NIDIFICATION.

First published in the " Journal of Travel and Na-
tural History" (No. 2), 1868. Now reprinted with
considerable emendations and additions, by which I
have endeavoured more clearly to express, and more
fully to illustrate, my meaning in those parts which
have been misunderstood by my critics.

VIII. — CREATION BY LAW.

First published in the " Quarterly Journal of
Science," October, 1867. Now reprinted with a few
alterations and additions.

Vlll PREFACE.

IX. — THE DEVELOPMENT OF HUMAN RACES UNDER
THE LAW OF NATURAL SELECTION.

First ' published in the "Anthropological Review,"
May, 1864. Now reprinted with a few important alter-
ations and additions. I had intended to have consider-
ably extended this essay, but on attempting it I found
that I should probably weaken the effect without add-
ing much to the argument. I have therefore preferred
to leave it as it was first written, with the exception
of a few ill-considered passages which never fully ex-
pressed my meaning. As it now stands, I believe it
contains the enunciation of an important truth.

X. — THE LIMITS OF NATURAL SELECTION AS APPLIED
TO MAN.

This is the further development of a few sentences
at the end of an article on " Geological Time and the
Origin of Species," which appeared in the " Quarterly
Review," for April, 1869. I have here ventured to
touch on a class of problems which are usually consi-
dered to be beyond the boundaries of science^ but
which, I believe, will one day be brought within her
domain.

For the convenience of those who are acquainted
with any of my essays in their original form, I sub-
join references to the more important additions and
alterations now made to them.

PREFACE. IX

ADDITIONS AND CORRECTIONS TO THE ESSAYS AS
ORIGINALLY PUBLISHED.

Essays I. and II. are unaltered, but short notes are
added at pp. 19, 24, 29, and 40.

III. — Mimicry, and other Protective Resemblances
among Animals.

PAGE

53 Additional illustration of protective colouring in

the case of the wood-dove and the robin.
63 On moths resembling bird's dung and mortar.
86 Correction of some names of African Papilios and

a reference to Mr. Trimen's observations.
89 Mr. Jenner Weir's observation on birds which

refused to eat Spilosoma menthrasti.
102 An additional case of snake mimicry in Oxyrhopus

trigeminus.

107 Mr. Salvin's case of mimicry among hawks.
113 Name, Diadema anomala, added.
117 to 122. Use of gay colours in caterpillars, with an
account of Mr. Jenner Weir's and Mr. Butler's
observations.

IV. — The Malayan Papilionidce or Swallow-tailed
Butterflies y as illustrative of the Theory of Natural
Selection.

135 to 140. Additions to the discussion on the rank of
the Papilionidse, and on the principles which
determine the comparative rank of groups in the
animal kingdom.

X PREFACE.

PAGE

164: Illustration of variability from Mr. Baker's re-
vision of the British Roses.

173 Additional facts, on local variations of colour.

15^6 Additional genus of birds (Ceycopsis) peculiar
to Celebes.

199, 200. Concluding remarks.

Nl.—The Philosophy of Birds' Nests.

218 On nesting of Terns and Gulls, rewritten.
220 to 222. Daines Barrington, and others, on the song
of birds.

223 On young birds learning to build, by memory and

imitation.

224 Levaillant, on mode of nest-building.
229 On imperfect adaptation in birds' nests.

V1L— A Theory of Birds' Nests.

231, 232. Introductory passages modified, with some
omissions.

233 How modifications of organization would affect the
form of the nest.

235 Illustration from the habits of children and savages.

235, 236. Objection t§ term " hereditary habit "
answered.

237 Passage rewritten, on more or less variable char-
acters in relation to nidification.

248 On males choosing or rejecting females, and on
the various modes in which colour may be
acquired by female birds.

PREFACE. XI

249 On probable ancestral colours of female birds.
255 Protective colouring of the Waxwing.

VIII. — Creation ly Law.

293 Amount of variation in dogs.

296, 297. The " Times " on Natural Selection.

298 to 300. On intermediate or generalized forms of
extinct animals as an indication of transmuta-
tion or development.

302 Tabular demonstration of the Origin of Species by
Natural Selection.

IX. — The development of Human Races, under
the law of Natural Selection.

316 On colour as perhaps correlated with immunity

from disease in man.

326, 327. On the probable future development of man.
330 Concluding paragraph rewritten.

London, March, 1870.

CONTENTS.

I. — Oil the Law which has regulated the introduction of Neiv
Species.

Geographical distribution dependent on Geologic Changes — A Law
deduced from well-known Geographical and Geological facts — The
form of a true system of Classification determined by this Law— Geo-
graphical Distribution of Organisms — Geological Distribution of the
forms of Life — High Organization of very ancient Animals consistent
with this Law — Objections to Forbes' Theory of Polarity — Eudi-
mentary Organs— Conclusion Pp. 1 — 25

II. — On the Tendency of Varieties to depart indefinitely from the
Original Type.

Instability of Varieties supposed to prove the permanent distinctness of
Species — The Struggle for Existence — The Law of Population of
Species — The Abundance or Earity of a Species dependent upon its
more or less perfect Adaptation to the Conditions of Existence —
Useful Variations will tend to Increase, useless or hurtful Variations
to Diminish — Superior Varieties will ultimately extirpate the Ori-
ginal Species — The Partial Eeversion of Domesticated Varieties
explained — Lamarck's Hypothesis very different from that now
advanced — Conclusion Pp. 26 — 44

III. — Mimicry, and other Protective Resemblances among
Animals.

Test of true and false Theories — Importance of the Principle of Utility
— Popular Theories of Colour in Animals — Importance of Conceal-
ment as influencing Colour — Special modifications of Colour — Theory
of Protective Colouring — Objection that Colour as being dangerous
should not exist in Nature — Mimicry — Mimicry amongJL/epidoptera
— Lepicloptera mimicking other Insects — Mimicry among Beetles —
Beetles mimicking other Insacts — Insects mimicking Species of other
Orders — Cases of Mimicry among the Vertebrata — Mimicry among
Snakes — Mimicry among Birds — Mimicry among Mammals — Objec-

XIV CONTESTS.

tions to Mr. Bates' Theory of Mimicry — Mimicry by Female Insects
only — Cause of the dull Colours of Female Birds — Use of the gaudy
Colours of many Caterpillars — Summary — General deductions as to
Colour in Nature — Conclusion Pp. 45 — 129

IY. — TJie Malayan Papilionidce, or Swallow-tailed Butterflies,
as illustrative of the Theory of Natural Selection.

Special value of the Diurnal Lepidoptera for inquiries of this Nature —
Question of the rank of the Papilionidae — Distribution of the Papi-
lionidie — Definition of the word Species— Laws and Modes of Varia-
tion— Simple Yariability — Polymorphism or Dimorphism — Local
form or variety — Co-existing Variety — Race or Subspecies — Species
— Variation as specially influenced by Locality — Local Variation of
Size — Local Variation of Form — Local Variations of Colour — Re-
marks on the facts of Local Variation — Mimicry — Concluding
Remarks on Variation in Lepidoptera — Arrangement — Geographical
Distribution — Remarkable peculiarities of the island of Celebes —
Concluding Remarks Pp. 130—200

Y. — On Instinct in Man and Animals.

How Instinct may be best Studied — Definition of Instinct — Does Man
possess Instincts ? — How Indians travel through unknown and track-
less Forests Pp. 201— 210

YL— The Philosophy of Birds' Nests.

Instinct or Reason in the Construction of Birds' Nests — Do Men build
by Reason or by Imitation ? — Why does each Bird build a peculiar
kind of Nest ? — How do young Birds learn to build their first Nest ?
Do Birds sing by Instinct or by Imitation ? — Man's Works mainly
Imitative — Birds do Alter and Improve their Nests when altered con-
ditions require it — Conclusion Pp. 211 — 230

VII. — A Theory of Birds' Nests ; showing the relation of certain
differences of colour in female birds to their mode of nidifi-
cation.

Changed Conditions and persistent Habits as influencing Nidification —
Classification of Nests — Sexual differences of Colour in Birds — The
Law which connects the Colours of Female Birds with the mode of
Nidification — What the Facts Teach us — Colour more variable than

CONTENTS. XV

Structure or Habits, and therefore the Character which has generally
been modified — Exceptional cases confirmatory of the above Explana-
tion— Eeal or apparent exceptions to the Law stated at p. 240 —
Various modes of Protection of Animals — Females of some groups
require and obtain more Protection than the Males — Conclusion

Pp. 231- 263

YIII. — Creation by Law.

laws from which the Origin of Species may be deduced — Mr. Darwin's
Metaphors liable to Misconception — A case of Orchis-structure ex-
plained by Natural Selection — Adaptation brought about by General
Laws— Beauty in Nature — How new Forms are produced by Varia-
tion and Selection — The Objection that there are Limits to Variation
— Objection to the argument from Classification — The Times on
Natural Selection — Intermediate or generalized forms of Extinct
Animals an indication of Transmutation or Development — Conclu-
sion— A Demonstration of the Origin of Species . Pp. 264 — 301

IX. — The Development of Human Races under the Law of
Natural Selection.

Wide difference of Opinion as to Man's Origin — Outline of the Theory
of Natural Selection — Different effects of Natural Selection on
Animals and on Man — Influence of External Nature in the develop-
ment of the Human Mind — Extinction of Lower Eaces — The Origin
of the Eaces of Man — The Bearing of these views on the Antiquity
of Man — Their Bearing on the Dignity and Supremacy of Man —
Their Bearing on the future Development of Man — Summary — Con-
clusion Pp. 302—331

X. — The Limits of Natural Selection as applied to Man.

What Natural 'Selection can Not do — The Brain of the Savage shown
to be Larger than he Needs it to be — Size of Brain an important
Element of Mental Power — Comparison of the Brains of Man and of
Anthropoid Apes — Eange of intellectual power in Man — Intellect of
Savages and of Animals compared — The use of the Hairy Covering
of Mammalia — The Constant absence of Hair from certain p irts of
Man's body a remarkable Phenomenon — Savage Man feels the want
of this Hairy Covering — Man's Naked Skin could not have been pro-
duced by Natural Selection — Feet and Hands of Man considered as

XVI CONTENTS.

Difficulties on the Theory of Natural Selection — The Origin of Some
of Man's Mental Faculties, by the preservation of Useful Variations,
not possible — Difficulty as to the Origin of the Moral Sense — Sum-
vmary of the Argument as to the Insufficiency of Natural Selection to
account for the Development of Man — The Origin of Consciousness
— The Nature of Matter — Matter is Force — All Force ia probably
Will-force— Conclusion .... . Pp. 332— 371

I.

ON THE LAW WHICH HAS REGULATED
THE INTRODUCTION OF NEW SPECIES.*

Geographical Distribution dependent on Geologic
Changes.

EVERY naturalist who has directed his attention to
the subject of the geographical distribution of animals
and plants, must have been interested in the singular
facts which it presents. Many of these facts are quite
different from what would have been anticipated,
and have hitherto been considered as highly curious,
but quite inexplicable. None of the explanations
attempted from the time of Linnseus are now
considered at all satisfactory ; none of them have
given a cause sufficient to account for the facts
known at the time, or comprehensive enough to
include all the new facts which have since been, and
are daily being added. Of late years, however, a
great light has been thrown upon the subject by
geological investigations, which have shown that the
present state of the earth and of the organisms now

* Written at Sarawak in February, 1855, and published in
the " Annals and Magazine of Natural History," September,
1855.

B

A ON THE LAW WHICH HAS REGULATED

inhabiting it, is but the last stage of a long and
uninterrupted series of changes which it has under-
gone, and consequently, that to endeavour to explain
and account for its present condition without any
reference to those changes (as has frequently been
done) must lead to very imperfect and erroneous
conclusions.

The facts proved by geology are briefly these : —
That during an immense, but unknown period, the
surface of the earth has undergone successive
changes; land has sunk beneath the ocean, while
fresh land has risen up from it; mountain chains
have been elevated ; islands have been formed into
continents, and continents submerged till they have
become islands ; and these changes have taken place,
not once merely, but perhaps hundreds, perhaps
thousands of times : — That all these operations have
been more or less continuous, but unequal in their
progress, and during the whole series the organic
life of the earth has undergone a corresponding
alteration. This alteration also has been gradual,
but complete ; after a certain interval not a single-
species existing which had lived at the commence-
ment of the period. This complete renewal of the
forms of life also appears to have occurred several
times :— That from the last of the geological epochs
to the present or historical epoch, the change of
organic life has been gradual : the first appearance
of animals now existing can in many cases be traced,
their numbers gradually increasing in the more re-

THE INTRODUCTION OF NEW SPECIES. 3

cent formations, while other species continually die
out and disappear, so that the present condition of
the organic world is clearly derived by a natural
process of gradual extinction and creation of species
from that of the latest geological periods. We may
therefore safely infer a like gradation and natural
sequence from one geological epoch to another.

Now, taking this as a fair statement of the results
of geological inquiry, we see that the present geo-
graphical distribution of life upon the earth must
be the result of all the previous changes, both of the
surface of the earth itself and of its inhabitants.
Many causes, no doubt, have operated of which we
must ever remain in ignorance, and we may, there-
fore, expect to find many details very difficult of
explanation, and in attempting to give one, must
allow ourselves to call into our service geological
changes which it is highly probable may have
occurred, though we have no direct evidence of their
individual operation.

The great increase of our knowledge within the
last twenty years, both of the present and past history
of the organic world, has accumulated a body of
facts which should afford a sufficient foundation for
a comprehensive law embracing and explaining them
all, and giving a direction to new researches. It is
about ten years since the idea of such a law sug-
gested itself to the writer of this essay, and he has
since taken every opportunity of testing it by all
the newly-ascertained facts with which lie has become

B 2

4 ON THE LAW WHICH HAS REGULATED

acquainted, or has been able to observe himself.
These have all served to convince him of the correct-
ness of his hypothesis. Fully to enter into such a
subject would occupy much space, and it is only in
consequence of some views having been lately pro-
mulgated, he believes, in a wrong direction, that he
now ventures to present his ideas to the public, with
only such obvious illustrations of the arguments and
results as occur to him in a place far removed from
all means of reference and exact information.

A Law deduced from well-known Geographical and
Geological Facts.

The following propositions in Organic Geography
and Geology give the main facts on which the
hypothesis is founded.

Geography.

1. Large groups, such as classes and orders, are
generally spread over the whole earth, while smaller
ones, such as families and genera, are frequently
confined to one portion, often to a very limited dis-
trict.

2. In widely distributed families the genera are
often limited in range ; in widely distributed genera,
well marked groups of species are peculiar to each
geographical district.

3. When a group is confined to one district, and
is rich in species, it is almost invariably the case
that the most closely allied species are found in the
same locality or in closely adjoining localities, and

THE INTRODUCTION OF NEW SPECIES. 5

that therefore the natural sequence of the species by
affinity is also geographical.

4. In countries of a similar climate, but separated
by a wide sea or lofty mountains, the families, genera
and species of the one are often represented by
closely allied families, genera and species peculiar to-
the other.

Geology.

5. The distribution of the organic world in time is
very similar to its present distribution in space.

6. Most of the larger and some small groups ex-
tend through several geological periods.

7. In each period, however, there are peculiar
groups, found nowhere else, and extending through
one or several formations.

8. Species of one genus, or genera of one family
occurring in the same geological time are more closely
allied than those separated in time.

9. As generally in geography no species or genus
occurs in two very distant localities without being
also found in intermediate places, so in geology the
life of a species or genus has not been interrupted.
In other words, no group or species has come into
existence twice.

10. The following law may be deduced from these
facts : — Evert/ species has come into existence coincident
both in space and time icith a pre-existing closely allied
species.

This law agrees with, explains and illustrates all
the facts connected with the following; branches of

6 ON THE LAW WHICH HAS REGULATED

the subject : — 1st. The system of natural affinities.
2nd. The distribution of animals and plants in
space. 3rd. The same in time, including all the
phenomena of representative groups, and those
which Professor Forbes supposed to manifest polar-
ity. 4th. The phenomena of rudimentary organs.
We will briefly endeavour to show its bearing upon
each of these.

The Form of a true system of Classification determined
by this Law.

If the law above enunciated be true, it follows that
the natural series of affinities will also represent the
order in which the several species came into exist-
ence, each one having had for its immediate anti-
type a closely allied species existing at the time of
its origin. It is evidently possible that two or three
distinct species may have had a common antitype,
and that each of these may again have become the
antitypes from which other closely allied species were
created. The effect of this would be, that so long as
each species has had but one new species formed on
its model, the line of affinities will be simple, and
may be represented by placing the several species in
direct succession in a straight line. But if two or
more species have been independently formed on the
plan of a common antitype, then the series of affini-
ties will be compound, and can only be represented
by a forked or many branched line. Now, all at-
tempts at a Natural classification and arrangement

THE INTRODUCTION OF NEW SPECIES. 7

of organic beings show, that both these plans have
obtained in creation. Sometimes the series of affini-
ties can be well represented for a space by a direct
progression from species to species or from group to
group, but it is generally found impossible so to con-
tinue. There constantly occur two or more modifica-
tions of an organ or modifications of two distinct
organs, leading us on to two distinct series of species,
which at length differ so much from each other as
to form distinct genera or families. These are the
parallel series or representative groups of naturalists,
and they often occur in different countries, or are
found fossil in different formations. They are said
to have an analogy to each other when they are so
far removed from their common antitype as to differ
in many important points of structure, while they
still preserve a family resemblance. We thus see how
difficult it is to determine in every case whether a
given relation is an analogy or an affinity, for it is
evident that as we go back along the parallel or -diver-
gent series, towards the common antitype, the analogy
which existed between the two groups becomes an
affinity. We are also made aware of the difficulty
of arriving at a true classification, even in a small
and perfect group ; — in the actual state of nature it
is almost impossible, the species being so numerous
and the modifications of form and structure so varied,
arising probably from the immense number of species
which have served as antitypes for the existing spe-
cies, and thus produced a complicated branching of

8 ON THE LAW WHICH HAS REGULATED

the lines of affinity, as intricate as the twigs of a
gnarled oak or the vascular system of the human
body. 'Again, if we consider that we have only frag-
ments of this vast system, the stem and main branches
being represented by extinct species of which we have
no knowledge, while a vast mass of limbs and boughs
and minute twigs and scattered leaves is what we
have to place in order, and determine the true posi-
tion each originally occupied with regard to the others,
the whole difficulty of the true Natural System of
classification becomes apparent to us.

We shall thus find ourselves obliged to r.eject
all those systems of classification which arrange
species or groups in circles, as well as those
which fix a definite number for the divisions of
each group. The latter class have been very gener-
ally rejected by naturalists, as contrary to nature,
notwithstanding the ability with which they have
been advocated ; but the circular system of affini-
ties seems to have obtained a deeper hold, many
eminent naturalists having to some extent adopted
it. We have, however, never been able to find a
case in which the circle has been closed by a
direct and close affinity. In most cases a palpable
analogy has been substituted, in others the affinity
is very obscure or altogether doubtful. The com-
plicated branching of the lines of affinities in
extensive groups must also afford great facilities
for giving a show of probability to any such
purely artificial arrangements. Their death - blow

THE INTRODUCTION OF NEW SPECIES. 9

was given by the admirable paper of the lamented
Mr. Strickland, published in the "Annals of Na-
tural History," in which he so clearly showed the
true synthetical method of discovering the Natural
System.

Geographical Distribution of Organisms.

If we now consider the geographical distribu-
tion of animals and plants upon the earth, we
shall find all the facts beautifully in accordance
with, and readily explained by, the present hypo-
thesis. A country having species, genera, and
whole families peculiar to it, will be the neces-
sary result of its having been isolated for a long
period, sufficient for many series of species to
have been created on the type of pre-existing
ones, which, as well as many of the earlier-
formed species, have become extinct, and thus
made the groups appear isolated. If in any case
the antitype had an extensive range, two or more
groups of species might have been formed, each
varying from it in a different manner, and thus
producing several representative or analogous groups.
The Sylviadas of Europe and the Sylvicolidse of
North America, the Heliconidae of South America
and the Euploeas of the East, the group of Tro-
gons inhabiting Asia, and that peculiar to South
America, are examples that may be accounted for
in this manner.

Such phenomena as are exhibited by the Gala-

10 ON THE LAW WHICH HAS REGULATED

pagos Islands, which contain littte groups of plants
and animals peculiar to themselves, but most nearly
allied to those of South America, have not hither-
to received any, even a conjectural explanation.
The Galapagos are a volcanic group of high anti-
quity, and have probably never been more closely
connected with the continent than they are at
present. They must have been first peopled, like
other newly-formed islands, by the action of winds
and currents, and at a period sufficiently remote
to have had the original species die out, and the
modified prototypes only remain. In the same way
we can account for the separate islands having each
their peculiar species, either on the supposition that
the same original emigration peopled the whole of
the islands with the same species from which differ-
ently modified prototypes were created, or that the
islands were successively peopled from each other,
but that new species have been created in each on
the plan of the pre-existing ones. St. Helena is a
similar case of a very ancient island having obtained
an entirely peculiar, though limited, flora. On the
other hand, no example is known of an island which
can be proved geologically to be of very recent
origin (late in the Tertiary, for instance), and yet
possesses generic or family groups, or even many
species peculiar to itself.

When a range of mountains has attained a great
elevation, and has so remained during a long geolo-
gical period, the species of the two sides at and

THE INTRODUCTION OF NEW SPECIES. 11

near their bases will be often very different, repre-
sentative species of some genera occurring, and even
whole genera being peculiar to one side only, as is
remarkably seen in the case of the Andes and Rocky
Mountains. A similar phenomenon occurs when an
island has been separated from a continent at a very
early period. The shallow sea between the Peninsula
of Malacca, Java, Sumatra and Borneo was probably
a continent or large island at an early epoch, and
may have become submerged as the volcanic ranges
of Java and Sumatra were elevated. The organic
results we see in the very considerable number of
species of animals common to some or all of these
countries, while at the same time a number of closely
allied representative species exist peculiar to each,
showing that a considerable period has elapsed since
their separation. The facts of geographical distribu-
tion and of geology may thus mutually explain each
other, in doubtful cases, should the principles here
advocated be clearly established.

In all those cases in which an island has been
separated from a continent, or raised by volcanic or
coralline action from the sea, or in which a moun-
tain-chain has been elevated in a recent geological
epoch, the phsenomena of peculiar groups or even
of single representative species will not exist. Our
own island is an example of this, its separation from
the continent being geologically very recent, and we
have consequently scarcely a species which is pecu-
liar to it; while the Alpine range, one of the most

12 OX THE LAW WHICH HAS REGULATED

recent mountain elevations, separates faunas and floras
which scarcely differ more than may be due to climate
and latitude alone.

The series of facts alluded to in Proposition (3),
of closely allied species in rich groups being found
geographically near each other, is most striking and
important. Mr. Lovell Reeve has well exemplified it
in his able and interesting paper on the Distribution
of the Bulimi. It is also seen in the Humming-
birds and Toucans, little groups of two or three
closely allied species being often found in the same
or closely adjoining districts, as we have had the
good fortune of personally verifying. Fishes give
evidence of a similar kind : each great river has
its peculiar genera, and in more extensive genera
its groups of closely allied species. But it is the
same throughout Nature ; every class and order of
animals will contribute similar facts. Hitherto no
attempt has been made to explain these singular
phenomena, or to show how they have arisen. Why
are the genera of Palms and of Orchids in almost
every case confined to one hemisphere ? Why are
the closely allied species of brown-backed Trogons all
found in the East, and the green-backed in. the
West? Why are the Macaws and the Cockatoos
similarly restricted ? Insects furnish a countless
number of analogous examples ; — the Goliathi of
Africa, the OrnithopteraB of the Indian Islands, the
Heliconidse of South America, the DanaidaB of the
East, and in all, the most closely allied species found

THE INTRODUCTION OF NEW SPECIES. 13

in geographical proximity. The question forces itself
upon every thinking mind, — why are these things
so ? They could not be as they are had no law
regulated their creation and dispersion. The law
here enunciated not merely explains, but necessitates
the facts we see to exist, while the vast and long-
continued geological changes of the earth readily
account for the exceptions and apparent discrepan-
cies that here and there occur. The writer's object
in putting forward his views in the present imper-
fect manner is to submit them to the test of other
minds, and to be made aware of all the facts
supposed to be inconsistent with them. As his
hypothesis is one which claims acceptance solely
as explaining and connecting facts which exist in
nature, he expects facts alone to be brought to dis-
prove it, not a priori arguments against its pro-
bability.

Geological Distribution of the Forms of Life.

The phenomena of geological distribution are ex-
actly analogous to those of geography. Closely allied
species are found associated in the same beds, and
the change from species to species appears to have
been as gradual in time as in space. Geology, how-
ever, furnishes us with positive proof of the extinc-
tion and production of species, though it does not
inform us how either has taken place. The extinction
of species, however, offers but little difficulty, and
the modus operandi has been well illustrated bv Sir

14 ON THE LAW WHICH HAS EEGULATED

C. Lyell in his admirable " Principles." Geological
changes, however gradual, must occasionally have
modified external conditions to such an extent as
to have rendered the existence of certain species
impossible. The extinction would in most cases be
effected by a gradual dying-out, but in some in-
stances there might have been a sudden destruction
of a species of limited range. To discover how the
extinct species have from time to time been replaced
by new ones down to the very latest geological period,
is the most difficult, and at the same time the most
interesting problem in the natural history of the
earth. The present inquiry, which seeks to elimi-
nate from known facts a law which has determined,
to a certain degree, what species could and did ap-
pear at a given epoch, may, it is hoped, be consi-
dered as one step in the right direction towards a
complete solution of it.

High Organization of very ancient Animals consistent
ivith this Law.

Much discussion has of late years taken place on
the question, whether the succession of life upon the
globe has been from a lower to a higher degree of
organization. The admitted facts seem to show that
there has been a general, but not a detailed pro-
gression. Mollusca and Eadiata existed before Ver-
tebrata, and the progression from Fishes to Reptiles
and Mammalia, and also from the lower mammals
to the higher, is indisputable. On the other hand.

THE INTRODUCTION OF NEW SPECIES. 15

it is said that the Mollusca and Radiata of the very
earliest periods were more highly organized than
the great mass of those now existing, and that the
very first fishes that have been discovered are by no
means the lowest organised of the class. Now it is
believed the present hypothesis will harmonize with
all these facts, and in a great measure serve to
explain them ; for though it may appear to some
readers essentially a theory of progression, it is in
reality only one of gradual change. It is, however,
by no means difficult to show that a real progression
in the scale of organization is perfectly consistent
with all the appearances, and even with apparent
retrogression, should such occur.

Returning to the analogy of a branching tree, as
the best mode of representing the natural arrange-
ment of species and their successive creation, let us
suppose that at an early geological epoch any group
(say a class of the Mollusca) has attained to a great
richness of species and a high organization. Now
let this great branch of allied species, by geologi-
cal mutations, be completely or partially destroyed.
Subsequently a new branch springs from the same
trunk, that is to say, new species are successively
created, having for their antitypes the same lower
organized species which had served as the antitypes
for the former group, but which have survived the
modified conditions which destroyed it. This new
group being subject to these altered conditions, has
modifications of structure and organization given

16 ON THE LAW WHICH HAS REGULATED

to it, and becomes the representative group of the
former one in another geological formation. It may,
however, happen, that though later in time, the new
series of species may never attain to so high a
degree of organization as those preceding it, but
in its turn become extinct, and give place to yet
another modification from the same root, which may
be of higher or lower organization, more or less
numerous in species, and more or less varied in form
and structure than either of those which preceded it.
Again, each of these groups may not have become
totally extinct, but may have left a few species, the
modified prototypes of which have existed in each
succeeding period, a faint memorial of their former
grandeur and luxuriance. Thus every case of ap-
parent retrogression may be in reality a progress,
though an interrupted one : when some monarch of
the forest loses a limb, it may be replaced by a
feeble and sickly substitute. The foregoing remarks
appear to apply to the case of the Mollusca, which,
at a very early period, had reached a high organi-
zation and a great development of forms and species
in the testaceous Cephalopoda. In each succeeding
age modified species and genera replaced the former
ones which had become extinct, and as we approach
the present sera, but few and small representatives of
the group remain, while the Gasteropods and Bi-
valves have acquired an immense preponderance. In
the long series of changes the earth has undergone,
the process of peopling it with organic beings has

THE INTRODUCTION OF NEW SPECIES. 17

been continually going on, and whenever any of the
higher groups have become nearly or quite extinct,
the lower forms which have better resisted the modi-
fied physical conditions have served as the antitypes
on which to found the new races. In this manner
alone, it is believed, can the representative groups
at successive periods, and the risings and fallings in
the scale of organization, be in every case explained.

Objections to Forbes* Theory of Polarity.

The hypothesis of polarity, recently put forward by
Professor Edward Forbes to account for the abun-
dance of generic forms at a very early period and at
present, while in the intermediate epochs there is
a gradual diminution and impoverishment, till the
minimum occurred at the confines of the Palaeozoic
and Secondary epochs, appears to us quite unne-
cessary, as the facts may be readily accounted for
on the principles already laid down. Between the
Palaeozoic and Neozoic periods of Professor Forbes,
there is scarcely a species in common, and the
greater part of the genera and families also dis-
appear to be replaced by new ones. It is almost
universally admitted that such a change in the
organic world must have occupied a vast period of
time. Of this interval we have no record ; pro-
bably because the whole area of the early formations
now exposed to our researches was elevated at the
end of the Palaeozoic period, and remained so through
the interval required for the organic changes which

c

18 ON THE LAW WHICH HAS REGULATED

resulted in the fauna and flora of the Secondary-
period. The records of this interval are buried
beneath the ocean which covers three-fourths of the
globe. Now it appears highly probable that a long
period of quiescence or stability in the physical con-
ditions of a district would be most favourable to the
existence of organic life in the greatest abundance,
both as regards individuals and also as to variety of
species and generic group, just as we now find that
the places best adapted to the rapid growth and in-
crease of individuals also contain the greatest pro-
fusion of species and the greatest variety of forms,
— the tropics in comparison with the temperate and
arctic regions. On the other hand, it seems no
less probable that a change in the physical conditions
of a district, even small in amount if rapid, or
even gradual if to a great amount, would be highly
unfavourable to the existence of individuals, might
cause the extinction of many species, and would pro-
bably be equally unfavourable to the creation of new
ones. In this too we may find an analogy with the
present state of our earth, for it has been shown to
be the violent extremes and rapid changes of phy-
sical conditions, rather than the actual mean state
in the temperate and frigid zones, which renders
them less prolific than the tropical regions, as exem-
plified by the great distance beyond the tropics
to which tropical forms penetrate when the climate
is equable, and also by the richness in species and
forms of tropical mountain regions which principally

THE INTRODUCTION OF NEW SPECIES. 19

differ from the temperate zone in the uniformity of
their climate. However this may be, it seems a
fair assumption that during a period of geological
repose the new species which we know to have been
created would have appeared, that the creations
would then exceed in number the extinctions, and
therefore the number of species would increase.
In a period of geological activity, on the other hand,
it seems probable that the extinctions might exceed
the creations, and the number of species consequently
diminish. That such effects did take place in con-
nexion with the causes to which we have imputed
them, is shown in the case of the Coal formation,
the faults and contortions of which show a period of
great activity and violent convulsions, and it is in
the formation immediately succeeding this that the
poverty of forms of life is most apparent. We
have then only to suppose a long period of somewhat
similar action during the vast unknown interval at
the termination of the Palaeozoic period, and then
a decreasing violence or rapidity through the Second-
ary period, to allow for the gradual repopulation of
the earth with varied forms, and the whole of the
facts are explained.* We thus have a clue to the
increase of the forms of life during certain periods,
and their decrease during others, without recourse

* Professor Ramsay has since shown that a glacial epoch
probably occurred at the time of the Permian formation,
which will more satisfactorily account for the comparative
poverty of species.

G 2

20 ON THE LAW WHICH HAS REGULATED

to any causes but those we know to have existed,
and to effects fairly deducible from them. The pre-
cise manner in which the geological changes of the
early formations were effected is so extremely
obscure, that when we can explain important facts
by a retardation at one time and an acceleration at
another of a process which we know from its nature
and from observation to have been unequal, — a cause
so simple may surely be preferred to one so obscure
and hypothetical as polarity.

I would also venture to suggest some reasons
against the very nature of the theory of Professor
Forbes. Our knowledge of the organic world
during any geological epoch is necessarily very im-
perfect. Looking at the vast numbers of species
and groups that have been discovered by geologists,
this may be doubted ; but we should compare their
numbers not merely with those that now exist upon
the earth, but with a far larger amount. We have
no reason for believing that the number of species
on the earth at any former period was much less
than at present ; at all events the aquatic portion,
with which geologists have most acquaintance, was
probably often as great or greater. Now we know
that there have been many complete changes of
species ; new sets of organisms have many times been
introduced in place of old ones which have become
extinct, so that the total amount which have existed
on the earth from the earliest geological period must
have borne about the same proportion to those now

THE INTRODUCTION OF NEW SPECIES. 21

living, as the whole human race who have lived and
died upon the earth, to the population at the present
time. Again, at each epoch, the whole earth was
no doubt, as now, more or less the theatre of life,
and as the successive generations of each species
died, their exuviae and preservable parts would be
deposited over every portion of the then existing
seas and oceans, which we have reason for supposing
to have been more, rather than less, extensive than
at present. In order then to understand our possible
knowledge of the early world and its inhabitants,
we must compare, not the area of the whole field of
our geological researches with the earth's surface,
but the area of the examined portion of each forma-
tion separately with the whole earth. For example,
during the Silurian period all the earth was Silurian,
and animals were living and dying, and depositing
their remains more or less over the whole area of the
globe, and they were probably (the species at least)
nearly as varied in different latitudes and longitudes
as at present. What proportion do the Silurian dis-
tricts bear to the whole surface of the globe, land and
sea (for far more extensive Silurian districts probably
exist beneath the ocean than above it), and what
portion of the known Silurian districts has been
actually examined for fossils ? Would the area of
rock actually laid open to the eye be the thousandth
or the ten-thousandth part of the earth's surface?
Ask the same question with regard to the Oolite or
the Chalk, or even to particular beds of these when

22 ON THE LAW WHICH HAS REGULATED

they differ considerably in their fossils, and you may
then get some notion of how small a portion of the
whole we know.

But yet more important is the probability, nay
almost the certainty, that whole formations contain-
ing the records of vast geological periods are entirely
buried beneath the ocean, and for ever beyond our
reach. Most of the gaps in the geological series
may thus be filled up, and vast numbers of un-
known and unimaginable animals, which might help
to elucidate the affinities of the numerous isolated
groups which are a perpetual puzzle to the zoologist,
may there be buried, till future revolutions may
raise them in their turn above the waters, to afford
materials for the study of whatever race of intelli-
gent beings may then have succeeded us. These con-
siderations must lead us to the conclusion, that our
knowledge of the whole series of the former inhabi-
tants of the earth is necessarily most imperfect and
fragmentary, — as much so as our knowledge of the
present organic world would be, were we forced to
make our collections and observations only in spots
equally limited in area and in number with those
actually laid open for the collection of fossils. Now,
the hypothesis of Professor Forbes is essentially one
that assumes to a great extent the completeness of
our knowledge of the whole series of organic beings
which have existed on the earth. This appears to
be a fatal objection to it, independently of all other
considerations. It may be said that the same ob-

THE INTRODUCTION OF NEW SPECIES. 23

jections exist against every theory on such a subject,
but this is not necessarily the case. The hypothesis
put forward in this paper depends in no degree
upon the completeness of our knowledge of the
former condition of the organic world, but takes
what facts we have as fragments of a vast whole,
and deduces from them something of the nature and
proportions of that whole which we can never know
in detail. It is founded upon isolated groups of
facts, recognizes their isolation, and endeavours to
deduce from them the nature of the intervening
portions.

Rudimentary Organs

Another important series of facts, quite in accord-
ance with, and even necessary deductions from, the
law now developed, are those of rudimentary organs.
That these really do exist, and in most cases
have no special function in the animal oeconomy,
is admitted by the first authorities in comparative
anatomy. The minute limbs hidden beneath the skin
in many of the snake-like lizards, the anal hooks
of the boa constrictor, the complete series of jointed
finger -bones in the paddle of the Manatus and
whale, are a few of the most familiar instances. In
botany a similar class of facts has been long re-
cognised. Abortive stamens, rudimentary floral en-
velopes and undeveloped carpels, are of the most
frequent occurrence. To every thoughtful naturalist
the question must arise, What are these for ? What
have they to do with the great laws of creation?

24 CN THE LAW WHICH HAS REGULATED

Do they not teach us something of the system of
Nature ? If each species has been created inde-
pendently, and without any necessary relations with
pre-existing species, what do these rudiments, these
apparent imperfections mean ? There must be a
cause for them ; they must be the necessary results
of some great natural law. Now, if, as it has been
endeavoured to be shown, the great law which has
regulated the peopling of the earth with animal and
vegetable life is, that every change shall be gradual;
that no new creature shall be formed widely differing
from anything before existing; that in this, as in
everything else in Nature, there shall be gradation
and harmony, — then these rudimentary organs are
necessary, and are an essential part of the system of
Nature. Ere the higher Vertebrata were formed, for
instance, many steps were required, and many organs
had to undergo modifications from the rudimental
condition in which only they had as yet existed.
We still see remaining an antitypal sketch of a wing
adapted for flight in the scaly flapper of the penguin,
and limbs first concealed beneath the skin, and then
weakly protruding from it, were the necessary gra-
dations before others should be formed fully adapted
for locomotion.* Many more of these modifica-
tions should we behold, and more complete series

* The theory of Natural Selection lias now taught us that
these are not the steps by which limbs have been formed ; and
that most rudimentary organs have been produced by abortion*
owing to disease, as explained by Mr. Darwin.

THE INTRODUCTION OF NEW SPECIES. 25

of them, had we a view of all the forms which have
ceased to live. The great gaps that exist between
fishes, reptiles, birds, and mammals would then, no
doubt, be softened down by intermediate groups, and
the whole organic world would be seen to be an
unbroken and harmonious system

Conclusion.

It has now been shown, though most briefly and
imperfectly, how the law that " Every species has come
into existence coincident both in time and space with a
pre-existing closely allied species" connects together
and renders intelligible a vast number of independent
and hitherto unexplained facts. \ The natural system
of arrangement of organic beings, their geographical
distribution, their geological sequence, the phenomena
of representative and substituted groups in all their
modifications, and the most singular peculiarities of
anatomical structure, are all explained and illus-
trated by it, in perfect accordance with the vast
mass of facts which the researches of modern na-
turalists have brought together, and, it is believed,
not materially opposed to any of them. It also
claims a superiority over previous hypotheses, on
the ground that it not merely explains, but necessi-
tates what exists. Granted the law, and many of
the most important facts in Nature could not have
been otherwise, but are almost as necessary deduc-
tions from it, as are the elliptic orbits of the planets
from the law of gravitation.

II.

ON THE TENDENCY OF VARIETIES TO
DEPART INDEFINITELY FROM THE
ORIGINAL TYPE.*

Instability of Varieties supposed to prove the permanent
distinctness of Species.

ONE of the strongest arguments which have been ad-
duced to prove the original and permanent distinct-
ness of species is, that varieties produced in a state of
domesticity are more or less unstable, and often have
a tendency, if left to themselves, to return to the
normal form of the parent species; and this insta-
bility is considered to be a distinctive peculiarity of
all varieties, even of those occurring among wild
animals in a state of nature, and to constitute a pro-
vision for preserving unchanged the originally created
distinct species.

In the absence or scarcity of facts and observa-
tions as to varieties occurring among wild animals,
this argument has had great weight with natural-
ists, and has led to a very general and somewhat

* Written at Ternate, February, 1858; and published in
the Journal of the Proceedings of the Linnsean Society for
August, 1858.

ON THE TENDENCY OF VAEIETIES, ETC. 27

prejudiced belief in the stability of species. Equally
general, however, is the belief in what are called
" permanent or true varieties," — races of animals
which continually propagate their like, but which
differ so slightly (although constantly) from some
other race, that the one is considered to be a variety
of the other. Which is the variety and which the
original species, there is generally no means of de-
termining, except in those rare cases in which the
one race has been known to produce an offspring
unlike itself and resembling the other. This, how-
ever, would seem quite incompatible with the " per-
manent invariability of species," but the difficulty is
overcome by assuming that such varieties have strict
limits, and can never again vary further from the
original type, although they may return to it, which,
from the analogy of the domesticated animals, is
considered to be highly probable, if not certainly
proved.

It will be observed that this argument rests en-
tirely on the assumption, that varieties occurring in
a state of nature are in all respects analogous to or
even identical with those of domestic animals, and
are governed by the same laws as regards their per-
manence or further variation. But it is the object
of the present paper to show that this assumption is
altogether false, that there is a general principle in
nature which will cause many varieties to survive
the parent species, and to give rise to successive
variations departing further and further from the

28 ON THE TENDENCY OF VARIETIES TO DEPART

original type, and which also produces, in domesti-
cated animals, the tendency of varieties to return to
the parent form.

The Struggle for Existence.

The life of wild animals is a struggle for exist-
ence. The full exertion of all their faculties and
all their energies is required to preserve their own
existence and provide for that of their infant off-
spring. The possibility of procuring food during the
least favourable seasons, and of escaping the attacks
of their most dangerous enemies, are the primary
conditions which determine the existence both of
individuals and of entire species. These conditions
will also determine the population of a species; and by
a careful consideration of all the circumstances we
may be enabled to comprehend, and in some degree
to explain, what at first sight appears so inex-
plicable— the excessive abundance of some species,
while others closely allied to them are very rare.

Tlie Law of Population of Species.

The general proportion that must obtain between
certain groups of animals is readily seen. Large
animals cannot be so abundant as small ones ; the
carnivora must be less numerous than the herbivora ;
eagles and lions can never be so plentiful as pigeons
and antelopes; and the wild asses of the Tartarian
deserts cannot equal in numbers the horses of the
more luxuriant prairies and pampas of America. The

INDEFINITELY FROM THE ORIGINAL TYPE. 29

greater or less fecundity of an animal is often con-
sidered to be one of the chief causes of its abun-
dance or scarcity; but a consideration of the facts
will show us that it really has little or nothing to
do with the matter. Even the least prolific of
animals would increase rapidly if unchecked, whereas
it is evident that the animal population of the globe
must be stationary, or perhaps, through the influence
of man, decreasing. Fluctuations there may be; but
permanent increase, except in restricted localities, is
almost impossible. For example, our own observa-
tion must convince us that birds do not go on
increasing every year in a geometrical ratio, as they
would do, were there not some powerful check to
their natural increase. Very few birds produce less
than two young ones each year, while many have
six, eight, or ten; four will certainly be below the
average ; and if we suppose that each pair produce
young only four times in their life, that will also be
below the average, supposing them not to die either
by violence or want of food. Yet at this rate how
tremendous would be the increase in a few years
from a single pair! A simple calculation will show
that in fifteen years each pair of birds would have
increased to nearly ten millions ! * whereas we have
no reason to believe that the number of the birds of
any country increases at all in fifteen or in one
hundred and fifty years. With such powers of in-

* This is under estimated. The number would really
amount to more than two thousand millions!

SO ON THE TENDENCY OF VARIETIES TO DEPART

crease the population must have reached its limits,
and have become stationary, in a very few years
after the origin of each species. It is evident, there-
fore, that each year an immense number of birds
must perish — as many in fact as are born ; and as
on the lowest calculation the progeny are each year
twice as numerous as their 'parents, it follows that,
whatever be the average number of individuals exist-
ing in any given country, twice that number must
perish annually, — a striking result, but one which
seems at least highly probable, and is perhaps under
rather than over the truth. It would therefore ap-
pear that, as far as the continuance of the species
and the keeping up the average number of indi-
viduals are concerned, large broods are superfluous.
On the average all above one become food for hawks
and kites, wild cats or weasels, or perish of cold
and hunger as winter comes on. This is strikingly
proved by the case of particular species ; for we
find that their abundance in individuals bears no
relation whatever to their fertility in producing off-
spring.

Perhaps the most remarkable instance of an im-
mense bird population is that of the passenger
pigeon of the United States, which lays only one,
or at most two eggs, and is said to rear gener-
ally but one young one. Why is this bird so
extraordinarily abundant, while others producing two
or three times as many young are much less plen-
tiful ? The explanation is not difficult. The food

INDEFINITELY FROM THE ORIGINAL TYPE. 31

most congenial to this species, and on which it
thrives best, is abundantly distributed over a very
extensive region, offering such differences of soil
and climate, that in one part or another of the
area the supply never fails. The bird is capable of
a very rapid and long-continued flight, so that it
can pass without fatigue over the whole of the dis-
trict it inhabits, and as soon as the supply of food
begins to fail in one place is able to discover
a fresh feeding-ground. This example strikingly
shows us that the procuring a constant supply of
wholesome food is almost the sole condition re-
quisite for ensuring the rapid increase of a given
species, since neither the limited fecundity, nor the
unrestrained attacks of birds of prey and of man
are here sufficient to check it. In no other birds
are these peculiar circumstances so strikingly com-
bined. Either their food is more liable to failure,
or they have not sufficient power of wing to search
for it over an extensive area, or during some
season of the year it becomes very scarce, and less
wholesome substitutes have to be found ; and thus,
though more fertile in offspring, they can never in-
crease beyond the supply of food in the least
favourable seasons.

Many birds can only exist by migrating, when
their food becomes scarce, to regions possessing a
milder, or at least a different climate, though, as
these migrating birds are seldom excessively abun-
dant, it is evident that the countries they visit are

32 o:r THE TENDENCY OF VARIETIES TO DEPAIZT

still deficient in a constant and abundant supply of
wholesome food. Those whose organization does not
permit them to migrate when their food becomes
periodically scarce, can never attain a large popu-
lation. This is probably the reasons why wood-
peckers are scarce with us, while in the tropics they
are among the most abundant of solitary birds.
Thus the house sparrrow is more abundant than the
redbreast, because its food is more constant and
plentiful, — seeds of grasses being preserved during
the winter, and our farm-yards and stubble-fields
furnishing an almost inexhaustible supply. Why, as
a general rule, are aquatic, and especially sea birds,
very numerous in individuals ? Not because they
are more prolific than others, generally the con-
trary ; but because their food never fails, the sea-
shores and river-banks daily swarming with a fresh
supply of small mollusca and Crustacea. Exactly
the same laws will apply to mammals. Wild cats
are prolific and have few enemies ; why then are
they never as abundant as rabbits ? The only in-
telligible answer is, that their supply of food is
more precarious. It appears evident, therefore, that
so long as a country remains physically unchanged,
the numbers of its animal population cannot ma-
terially increase. If one species does so, some others
requiring the same kind of food must diminish in
proportion. The numbers that die annually must be
immense ; and as the individual existence of each
animal depends upon itself, those that die must be

INDEFINITELY FROM THE ORIGINAL TYPE 33

the weakest — the very young, the aged, and the
diseased — while those that prolong their existence
can only be the most perfect in health and vigour —
those who are best able to obtain food regularly, and
avoid their numerous enemies. It is, as we com-
menced by remarking, " a struggle for existence," in
which the weakest and least perfectly organized
must always succumb.

The Abundance or Rarity of a Species dependent upon
its more or less perfect Adaptation to the Con-
ditions of Existence.

It seems evident that what takes place among the
individuals of a species must also occur among the
several allied species of a group, — viz., that those
which are best adapted to obtain a regular supply
of food, and to defend themselves against the attacks
of their enemies and the vicissitudes of the seasons,
must necessarily obtain and preserve a superiority
in population ; while those species which from some
defect of power or organization are the least capa-
ble of counteracting the vicissitudes of food-supply,
&c., must diminish in numbers, and, in extreme
cases, become altogether extinct. Between these ex-
tremes the species will present various degrees of
capacity for ensuring the means of preserving life ;
and it is thus we account for the abundance or rarity
of species. Our ignorance will generally prevent us
from accurately tracing the effects to their causes;
but could we become perfectly acquainted with the

D

34 ON THE TENDENCY OF VAEIETIES TO DEPART

organization and habits of the various species of ani-
mals, and could we measure the capacity of each for
performing the different acts necessary to its safety
and existence under all the varying circumstances by
which it is surrounded, we might be able even to
calculate the proportionate abundance of individuals
which is the necessary result.

If now we have succeeded in establishing these
two points — 1st, that the animal population of a
country is generally stationary, being kept down by a
periodical deficiency of food, and other checks; and,
2nd, that the comparative abundance or scarcity of the
individuals of the several species is entirely due to their
organization and resulting habits, which, rendering it
more difficult to procure a regular supply of food and
to provide for their personal safety in some cases than
in others, can only be balanced by a difference in the
population which have to exist in a given area — we
shall be in a condition to proceed to the consider-
ation of varieties, to which the preceding remarks
have a direct and very important application.

Useful Variations will tend to Increase ; useless or hurt-
fid Variations to Diminish.

Most or perhaps all the variations from the
typical form of a species must have some definite
effect, however slight, on the habits or capacities of
the individuals. Even a change of colour might, by
rendering them more or less distinguishable, affect
their safety; a greater or less development of hair

INDEFINITELY FROM THE ORIGINAL TYPE. 35

might modify their habits. More important changes,
such as an increase in the power or dimensions of
the limbs or any of the external organs, would
more or less affect their mode of procuring food
or the range of country which they could inhabit.
It is also evident that most changes would affect,
either favourably or adversely, the powers of pro-
longing existence. An antelope with shorter or
weaker legs must necessarily suffer more from the
attacks of the feline carnivora ; the passenger pigeon
with less powerful wings would sooner or later be
affected in its powers of procuring a regular supply
of food ; and in both cases the result must neces-
sarily be a diminution of the population of the
modified species. If, on the other hand, any species
should produce a variety having slightly increased
powers of preserving existence, that variety must
inevitably in time acquire a superiority in numbers.
These results must follow as surely as old age, in-
temperance, or scarcity of food produce an increased
mortality. In both cases there may be many
individual exceptions; but on the average the rule
will invariably be found to hold good. All varieties
will therefore fall into two classes — those which
under the same conditions would never reach the
population of the parent species, and those which
would in time obtain and keep a numerical su-
periority. Now, let some alteration of physical
conditions occur in the district — a long period of
drought, a destruction of vegetation by locusts, the

D 2

36 ay THE TENDENCY OF VARIETIES TO DEPART

irruption of some new carnivorous animal seeking
" pastures new " — any change in fact tending to
render existence more difficult to the species in
question, and tasking its utmost powers to avoid
complete extermination ; it is evident that, of all
the individuals composing the species, those forming
the least numerous and most feebly organized
variety would suffer first, and, were the pressure
severe, must soon become extinct. The same .causes
continuing in action, the parent species would next
suffer, would gradually diminish in numbers, and
with a recurrence of similar unfavourable conditions
might also become extinct. The superior variety
would then alone remain, and on a return to
favourable circumstances would rapidly increase in
numbers and occupy the place of the extinct species
and variety.

Superior Varieties will ultimately Extirpate the original
Species.

The variety would now have replaced the species,
of which it would be a more perfectly developed
and more highly organized form. It would be in
all respects better adapted to secure its safety, and
to prolong its individual existence and that of the
race. Such a variety could not return to the ori-
ginal form ; for that form is an inferior one, and
could never compete with it for existence. Granted,
therefore, a u tendency " to reproduce the original
type of the species, still the variety must ever re-

INDEFINITELY FROM THE ORIGINAL TYPE. 37

main preponderant in numbers, and under adverse
physical conditions again alone survive. But this
new, improved, and populous race might itself, in
course of time, give rise to new varieties, exhibiting
several diverging modifications of form, any of which,
tending to increase the facilities for preserving ex-
istence, must, by the same general law, in their
turn become predominant. Here, then, we have
progression and continued divergence deduced from the
general laws which regulate the existence of animals
in a state of nature, and from the undisputed fact
that varieties do frequently occur. It is not, how-
ever, contended that this result would be invariable;
a change of physical conditions in the district might
at times materially modify it, rendering the race
which had been the most capable of supporting ex-
istence under the former conditions now the least so,
and even causing the extinction of the newer and,
for a time, superior race, while the old or parent
species and its first inferior varieties continued to
flourish. Variations in unimportant parts might
also occur, having no perceptible effect on the life-
preserving powers ; and the varieties so furnished
might run a course parallel with the parent species,
either giving rise to further variations or returning
to the former type. All we argue for is, that cer-
tain varieties have a tendency to maintain their
existence longer than the original species, and this
tendency must make itself felt ; for though the doc-
trine of chances or averages can never be trusted to

38 ON THE TENDENCY OF VARIETIES TO DEPART

on a limited scale, yet, if applied to high numbers,
the results come nearer to what theory demands,
and, as we approach to an infinity of examples,
become strictly accurate. Now the scale on which
nature works is so vast — the numbers of individuals
and the periods of time with which she deals ap-
proach so near to infinity, than any cause, how-
ever slight, and however liable to be veiled and
counteracted by accidental circumstances, must in
the end produce its full legitimate results.

The Partial Reversion of Domesticated Varieties
explained.

Let us now turn to domesticated animals, and in-
quire how varieties produced among them are affected
by the principles here enunciated. The essential
difference in the condition of wild and domestic
animals is this, — that among the former, their well-
being and very existence depend upon the full exer-
cise and healthy condition of all their senses and
physical powers, whereas, among the latter, these are
only partially exercised, and in some cases are abso-
lutely unused. A wild animal has to search, and
often to labour, for every mouthful of food — to ex-
ercise sight, hearing, and smell in seeking it, and
in avoiding dangers, in procuring shelter from the
inclemency of the seasons, and in providing for the
subsistence and safety of its offspring. There is no
muscle of its body that is not called into daily and
hourly activity; there is no sense or faculty that is

INDEFINITELY FROM THE ORIGINAL TYPE. 39

not strengthened by continual exercise. The domes-
tic animal, on the other hand, has food provided
for it, is sheltered, and often confined, to guard it
against the vicissitudes of thq seasons, is carefully
secured from the attacks of its natural enemies, and
seldom even rears its young without human assist-
ance. Half of its senses and faculties become quite
useless, and the other half are but occasionally
called into feeble exercise, while even its muscular
system is only irregularly brought into action.

Now when a variety of such an animal occurs,
having increased power or capacity in any organ or
sense, such increase is totally useless, is never called
into action, and may even exist without the animal
ever becoming aware of it. In the wild animal, on
the contrary, all its faculties and powers being
brought into full action for the necessities of ex-
istence, any increase becomes immediately available,
is strengthened by exercise, and must even slightly
modify the food, the habits, and the whole economy
of the race. It creates as it were a new animal,
one of superior powers, and which will necessarily
increase in numbers and outlive those which are in-
ferior to it.

Again, in the domesticated animal all variations
have an equal chance of continuance ; and those
which would decidedly render a wild animal unable
to compete with its fellows and continue its existence
are no disadvantage whatever in a state of domesti-
city. Our quickly fattening pigs, short-legged sheep

40 ON THE TENDENCY OF VARIETIES TO DEPART

pouter pigeons, and poodle dogs could never have
come into existence in a state of nature, because
the very first step towards such inferior forms would
have led to the rapid extinction of the race; still
less could they now exist in competition with their
wild allies. The great speed but slight endurance
of the race horse, the unwieldly strength of the
ploughman's team, would both be useless in a state
of nature. If turned wild on the pampas, such ani-
mals would probably soon become extinct, or under
favourable circumstances might each gradually lose
those extreme qualities which would never be called
into action, and in a few generations revert to a
common type, which must be that in which the
various powers and faculties are so proportioned to
each other as to be best adapted to procure food and
secure safety, — that in which by the full exercise of
every part of its organisation the animal can alone
continue to live. Domestic varieties, when turned
wild, must return to something near the type of
the original wild stock, or become altogether extinct.*
We see, then, that no inferences as to the per-
manence of varieties in a state of nature can be
deduced from the observations of those occurring
among domestic animals. The two are so much op-
posed to each other in every circumstance of their

* That is, they will vary, and the variations which tend to
adapt them to the wild state, and therefore approximate them
to wild animals, will be preserved. Those individuals which do
not vary sufficiently will perish.

INDEFINITELY FROM THE ORIGINAL TYPE. 41

existence, that what applies to the one is almost sure
not to apply to the other. Domestic animals are ab-
normal, irregular, artificial ; they are subject to varia-
tions which never occur and never can occur in a state
of nature : their very existence depends altogether on
human care ; so far are many of them removed from
that just proportion of faculties, that true balance of
organisation, by means of which alone an animal left
to its own resources can preserve its existence and
continue its race.

Lamarck's Hypothesis very different from that now
advanced.

The hypothesis of Lamarck — that progressive changes
in species have been produced by the attempts of ani-
mals to increase the development of their own or-
gans, and thus modify their structure and habits — has
been repeatedly and easily refuted by all writers on
the subject of varieties and species, and it seems to
have been considered that when this was done the
whole question has been finally settled ; but the view
here developed renders such hypothesis quite un-
necessary, by showing that similar results must be
produced by the action of principles constantly at
work in nature. The powerful retractile talons of
the falcon- and the cat-tribes have not been produced
or increased by the volition of those animals; but
among the different varieties which occurred in the
earlier and less highly organized forms of these
groups, those always survived longest which had the

42 ON THE TENDENCY OF VARIETIES TO DEPART

greatest facilities for seizing their prey. Neither did
the giraffe acquire its long neck by desiring to reach
the foliage of the more lofty shrubs, and constantly
stretching it neck for the purpose, but because any
varieties which occurred among its antitypes with a
longer neck than usual at once secured a fresh range
of pasture over the same ground as their shorter-necked
companions, and on the first scarcity of food were
thereby enabled to outlive them. Even the peculiar
colours of many animals, more especially of insects, so
closely resembling the soil or leaves or bark on which
they habitually reside, are explained on the same
principle ; for though in the course of ages varieties
of many tints may have occurred, yet those races
having colours best adapted to concealment from their
enemies would inevitably survive the longest. We have
also here an acting cause to account for that balance
so often observed in nature, — a deficiency in one set
of organs always being compensated by an increased
development of some others — powerful wings accom-
panying weak feet, or great velocity making up for
the absence of defensive weapons ; for it has been
shown that all varieties in which an unbalanced
deficiency occurred could not long continue their
existence. The action of this principle is exactly
like that of the centrifugal governor of the steam
engine, which checks and corrects any irregularities
almost before they become evident; and in like
manner no unbalanced deficiency in the animal king-
dom can ever reach any conspicuous magnitude,

INDEFINITELY FROM THE ORIGINAL TYPE. 43

because it would make itself felt at the very first
step, by rendering existence difficult and extinction
almost sure soon to follow. An origin such as is
here advocated will also agree with the peculiar
character of the modifications of form and structure
which obtain in organized beings — the many lines
of divergence from a central type, the increasing
efficiency and power of a particular organ through
a succession of allied species, and the remarkable
persistence of unimportant parts, such as colour, tex-
ture of plumage and hair, form of horns or crests,
through a series of species differing considerably
in more essential characters. It also furnishes us
with a reason for that "more specialized structure"
which Professor Owen states to be a characteristic
of recent compared with extinct forms, and which
would evidently be the result of the progressive
modification of any organ applied to a special pur-
pose in the animal economy.

Conclusion.

We believe we have now shown that there is a
tendency in nature to the continued progression of
certain classes of varieties further and further from
the original type — a progression to which there ap-
pears no reason to assign any definite limits — and
that the same principle which produces this result
in a state of nature will also explain why domestic
varieties have a tendency, when they become wild,
to revert to the original type. This progression,

44 ON THE TENDENCY OF VARIETIES, ETC.

by minute steps, in various directions, but always
checked and balanced by the necessary conditions,
subject to which alone existence can be preserved,
may, it is believed, be followed out so as to agree
with all the phenomena presented by organized be-
ings, their extinction and succession in past ages,
and all the extraordinary modifications of form, in-
stinct and habits which they exhibit.

45

III.

MIMICRY, AND OTHER PROTECTIVE RE-
SEMBLANCES AMONG ANIMALS.

THERE is no more convincing proof of the truth of
a comprehensive theory, than its power of absorbing
and finding a place for new facts, and its capability
of interpreting phenomena which had been previously
looked upon as unaccountable anomalies. It is thus
that the law of universal gravitation and the undu-
latory theory of light have become established and
universally accepted by men of science. Fact after
tact has been brought forward as being apparently
inconsistent with them, and one after another these
very facts have been shown to be the consequences
of the laws they were at first supposed to disprove.
A false theory will never stand this test. Advancing
knowledge brings to light whole groups of facts
which it cannot deal with, and its advocates steadily
decrease in numbers, notwithstanding the ability
and scientific skill with which it may have been
supported. The great name of Edward Forbes did
not prevent his theory of " Polarity in the distribu-
tion of Organic beings in Time " from dying a
natural death ; but the most striking illustration of
the behaviour of a false theory is to be found in the
" Circular and Quinarian System " of classification

46 MIMICRY, AND OTHER PROTECTIVE

propounded by MacLeay, and developed by Swainson,
with an amount of knowledge and ingenuity that
have rarely been surpassed. This theory was emi-
nently attractive, both from its symmetry and com-
pleteness, and from the interesting nature of the
varied analogies and affinities which it brought to
light and made use of. The series of Natural His-
tory volumes in " Lardner's Cabinet Cyclopaedia,"
in which Mr. Swainson developed it in most de-
partments of the animal kingdom, made it widely
known ; and in fact for a long time these were
the best and almost the only popular text-books for
the rising generation of naturalists. It was favour-
ably received too by the older school, which was
perhaps rather an indication of its unsoundness. A
considerable number of well-known naturalists either
spoke approvingly of it, or advocated similar princi-
ples, and for a good many years it was decidedly
in the ascendent. With such a favourable introduc-
tion, and with such talented exponents, it must have
become established if it had had any germ of truth
in it; yet it quite died out in a few short years,
its very existence is now a matter of history ; and so
rapid was its fall that its talented creator, Swainson,
perhaps lived to be the last man who believed in it.

Such is the course of a false theory. That of a
true one is very different, as may be well seen by
the progress of opinion on the subject of Natural
Selection. In less than eight years "The Origin of
Species " has produced conviction in the minds of

RESEMBLANCES AMONG ANIMALS 47

a majority of the most eminent living men of science.
New facts, new problems, new difficulties as they
arise are accepted, solved or removed by this theory;
and its principles are illustrated by the progress and
conclusions of every well established branch of human
knowledge. It is the object of the present essay to
show how it has recently been applied to connect to-
gether and explain a variety of curious facts which
had long been considered as inexplicable anomalies.

Importance of the Principle of Utility.

Perphaps no principle has ever been announced
so fertile in results as that which Mr. Darwin so
earnestly impresses upon us, and which is indeed a
necessary deduction from the theory of Natural Se-
lection, namely — that none of the definite facts of
organic nature, no special organ, no characteristic
form or marking, no peculiarities of instinct or of
habit, no relations between species or between groups
of species — can exist, but which must now be or
once have been useful to the individuals or the races
which possess them. This great principle gives us a
clue which we can follow out in the study of many
recondite phenomena, and leads us to seek a mean-
ing and a purpose of some definite character in
minutisB which we should be otherwise almost sure
to pass over as insignificant or unimportant.

Popular Theories of Colour in Animals.
The adaptation of the external colouring of animals

48 M1M1CEY, AND CTREE PEOTECTIVE

to their conditions of life has long been recognised,
and has been imputed either to an originally created
specific peculiarity, or to the direct action of climate,
soil, or food. Where the former explanation has been
accepted, it has completely checked inquiry, since we
could never get any further than the fact of the
adaptation. There was nothing more to be known
about the matter. The second explanation was soon
found to be quite inadequate to deal with all the varied
phases of the phenomena, and to be contradicted by
many well-known facts. For example, wild rabbits are
always of grey or brown tints well suited for conceal-
ment among grass and fern. But when these rabbits
are domesticated, without any change of climate or
food, they vary into white or black, and these varie-
ties may be multiplied to any extent, forming white
or black races. Exactly the same thing has occurred
with pigeons ; and in the case of rats and mice,
the white variety has not been shown to be at all
dependent on alteration of climate, food, or other
external conditions. In many cases the wings of an
insect not only assume the exact tint of the bark
or leaf it is accustomed to rest on, but the form
and veining of the leaf or the exact rugosity of
the bark is imitated ; and these detailed modifications
cannot be reasonably imputed to climate or to food,
since in many cases the species does not feed on
the substance it resembles, and when it does, no
reasonable connexion can be shown to exist between
the supposed cause and the effect produced. It was

RESEMBLANCES AMONG ANIMALS. 49

reserved for the theory of Natural Selection to solve
all these problems, and many others which were not
at first supposed to be directly connected with them.
To make these latter intelligible, it will be necessary
to give a sketch of the whole series of phenomena
which may be classed under the head of useful or
protective resemblances.

Importance of Concealment as Influencing Colour.

Concealment, more or less complete, is useful to
many animals, and absolutely essential to some. Those
which have numerous enemies from which they can-
not escape by rapidity of motion, find safety in con-
cealment. Those which prey upon others must also
be so constituted as not to alarm them by their pre-
sence or their approach, or they would soon die of
hunger. Now it is remarkable in how many cases
nature gives this boon to the animal, by colouring it
with such tints as may best serve to enable it to es-
cape from its enemies or to entrap its prey. Desert
animals as a rule are desert-coloured. The lion is
a typical example of this, and must be almost in-
visible when crouched upon the sand or among
desert rocks and stones. Antelopes are all more or
less sandy-coloured. The camel is pre-eminently so.
The Egyptian cat and the Pampas cat are sandy
or earth-coloured. The Australian kangaroos are of
the same tints, and the original colour of the wild
horse is supposed to have been a sandy or clay-
colour.

50 MIMICRY, AND OTHER PROTECTIVE

The desert birds are still more remarkably pro-
tected by their assimilative hues. The stonechats, the
larks, the quails, the goatsuckers and the grouse,
which abound in the North African and Asiatic
deserts, are all tinted and mottled so as to resemble
with wonderful accuracy the average colour and as-
pect of the soil in the district they inhabit. The
Rev. H. Tristram, in his account of the ornithology
of North Africa in the 1st volume of the " Ibis,'*
says : "In the desert, where neither trees, brush-
wood, nor even undulation of the surface afford the
slightest protection to its foes, a modification of colour
which shall be assimilated to that of the surround-
ing country, is absolutely necessary. Hence without
exception the upper plumage of every bird, whether
lark, chat, sylvain, or sand-grouse, and also the fur
of all the s,,ialler mammals, and the skin of all tJie
snakes and lizards, is of one uniform isabelline or
sand colour." After the testimony of so able an
observer it is unnecessary to adduce further exam-
ples of the protective colours of desert animals.

Almost equally striking are the cases of arctic
animals possessing the white colour that best con-
ceals them upon snowfields and icebergs. The polar
bear is the only bear that is white, and it lives
constantly among snow and ice. The arctic fox, the
ermine and . the alpine hare change to white in
winter only, because in summer white would be
more conspicuous than any other colour, and there-
fore a danger rather than a protection; but the

RESEMBLANCES AMONG- ANIMALS. 51

American polar hare, inhabiting regions of almost
perpetual snow, is white all the year round. Other
animals inhabiting the same Northern regions do
not, however, change colour. The sable is a good
example, for throughout the severity of a Siberian
winter it retains its rich brown fur. But its habits
are such that it does not need the protection of
colour, for it is said to be able to subsist on fruits
and berries in winter, and to be so active upon the
trees as to catch small birds among the branches.
So also the woodchuck of Canada has a dark-brown
fur ; but then it lives in burrows and frequents river
banks, catching fish and small animals that live in
or near the water.

Among birds, the ptarmigan is a fine example of
protective colouring. Its summer plumage so exactly
harmonizes with the lichen-coloured stones among
which it delights to sit, that a person may walk
through a flock of them without seeing a single
bird; while in winter its white plumage is an
almost equal protection. The snow-bunting, the jer-
falcon, and the snowy owl are also white-coloured
birds inhabiting the arctic regions, and there can
be little doubt but that their colouring is to some
extent protective.

Nocturnal animals supply us with equally good illus-
trations. Mice, rats, bats, and moles possess the least
conspicuous of hues, and must be quite invisible at
times when any light colour would be instantly seen.
Owls and goatsuckers are of those dark mottled tints

E 2

52 MIMICRY, AND OTHER PROTECTIVE

that will assimilate with bark and lichen, and thus
protect them during the day, and at the same time
be inconspicuous in the dusk.

It is only in the tropics, among forests which never
lose their foliage, that we find whole groups of birds
whose chief colour is green. The parrots are the most
striking example, but we have also a group of green
pigeons in the East ; and the barbets, leaf-thrushes,
bee-eaters, white-eyes, turacos, and several smaller
groups, have so much green in their plumage as to
tend greatly to conceal them among the foliage.

Special Modifications of Colour.

The conformity of tint which has been so far shown
to exist between animals and their habitations is of
a somewhat general character; we will now consider
the cases of more special adaptation. If the lion is
enabled by his sandy colour readily to conceal him-
self by merely crouching down upon the desert, how,
it may be asked, do the elegant markings of the
tiger, the jaguar, and the other large cats agree
with this theory ? We reply that these are generally
cases of more or less special adaptation. The tiger
is a jungle animal, and hides himself among tufts
of grass or of bamboos, and in these positions the
vertical stripes with which his body is adorned must
so assimilate with the vertical stems of the bamboo,
as to assist greatly in concealing him from his ap-
proaching prey. How remarkable it is that besides
the lion and tiger, almost all the other large cats

RESEMBLANCES AMONG ANIMALS. 53

are arboreal in their habits, and almost all have
ocellated or spotted skins, which must certainly tend
to blend them with the background of foliage ; while
the one exception, the puma, has an ashy brown
uniform fur, and has the habit of clinging so closely
to a limb of a tree while waiting for his prey to
pass beneath as to be hardly distinguishable from the
bark.

Among birds, the ptarmigan, already mentioned,
must be considered a remarkable case of special
adaptation. Another is a South-American goatsucker
(Caprimulgus rupestris) which rests in the bright
sunshine on little bare rocky islets in the Upper Eio
Negro, where its unusually light colours so closely
resemble those of the rock and sand, that it can
scarcely be detected till trodden upon.

The Duke of Argyll, in his " Reign of Law," has
pointed out the admirable adaptation of the colours
of the woodcock to its protection. The various
browns and yellows and pale ash-colour that occur
in fallen leaves are all reproduced in its plumage, so
that when according to its habit it rests upon the
ground under trees, it is almost impossible to detect
it. In snipes the colours are modified so as to be
equally in harmony with the prevalent forms and
colours of marshy vegetation. Mr. J. M. Lester,
in a paper read before the Rugby School Natural
History Society, observes : — " The wood-dove, when
perched amongst the branches of its favourite fir, is
scarcely discernible ; whereas, were it among some

54 MIMICRY, AND OTHER PROTECTIVE

lighter foliage, the blue and purple tints in its plumage
would far sooner betray it. The robin redbreast too,
although it might be thought that the red on its breasfc
made it much easier to be seen, is in reality not at
all endangered by it, since it generally contrives to
get among some russet or yellow fading leaves, where
the red matches very well with the autumn tints,
and the brown of the rest of the body with the bare
branches."

Reptiles offer us many similar examples. The most
arboreal lizards, the iguanas, are as green as the leaves
they feed upon, and the slender whip-snakes are ren-
dered almost invisible as they glide among the foliage
by a similar colouration. How difficult it is some-
times to catch sight of the little green tree-frogs
sitting on the leaves of a small plant enclosed in a
glass case in the Zoological Gardens ; yet how much
better concealed must they be among the fresh green
damp foliage of a marshy forest. There is a North-
American frpor^' found on lichen-covered rocks and

-~ A

walls, which is so coloured as exactly to resemble
them, and as long as it remains quiet would certainly
escape detection. Some of the geckos which cling
motionless on the trunks of trees in the tropics, are
of such curiously marbled colours as to match exactly
with the bark they rest upon.

In every part of the tiopics there are tree-snakes
that twist among boughs and shrubs, or lie coiled up
on the dense masses of foliage. These are of many
distinct groups, and comprise both venomous and

RESEMBLANCES AMONG- ANIMALS. 55

harmless genera; but almost all of them are of a
beautiful green colour, sometimes more or less adorned
with white or dusky bands and spots. There can
be little doubt that this colour is doubly useful to
them, since it will tend to conceal them from their
enemies, and will lead their prey to approach them
unconscious of danger. Dr. Gunther informs me
that there is only one genus of true arboreal snakes
(Dipsas) whose colours are rarely green, but are of
various shades of black, brown, and olive, and these
are all nocturnal reptiles, and there can be little doubt
conceal themselves during the day in holes, so that the
green protective tint would be useless to them, and
they accordingly retain the more usual reptilian hues.
Fishes present similar instances. Many flat fish, as
for example the flounder and the skate, are exactly
the colour of the gravel or sand on which they
habitually rest. Among the marine flower gardens
of an Eastern coral reef the fishes present every
variety of gorgeous colour, while the river fish even
of the tropics rarely if ever have gay or conspicuous
markings. A very curious case of this kind of ad-
aptation occurs in the sea-horses (Hippocampus) of
Australia, some of which bear long foliaceous ap-
pendages resembling seaweed, and are of a brilliant
red colour ; and they are known to live among sea-
weed of the same hue, so that when at rest they
must be quite invisible. There are now in the aqua-
rium of the Zoological Society some slender green
pipe-fish which fasten themselves to any object at

56 MIMICRY, AND OTHER PROTECTIVE

the bottom by their prehensile tails, and float about
with the current, looking exactly like some simple
cylindrical algae.

It is, however, in the insect world that this
principle of the adaptation of animals to their en-
vironment is most fully and strikingly developed.
In order to understand how general this is, it is
necessary to enter somewhat into details, as we shall
thereby be better able to appreciate the significance
of the still more remarkable phenomena we shall
presently have to discuss. It seems to be in pro-
portion to their sluggish motions or the absence of
other means of defence, that insects possess the pro-
tective colouring. In the tropics there are thousands
of species of insects which rest during the day cling-
ing to the bark of dead or fallen trees ; and the
greater portion of these are delicately mottled with
gray and brown tints, which though symmetrically
disposed and infinitely varied, yet blend so completely
with the usual colours of the bark, that at two or
three feet distance they are quite undistinguishable.
In some cases a species is known to frequent only
one species of tree. This is the case with the com-
mon South American long -horned beetle (Onychocerus
scorpio) which, Mr. Bates informed me, is found
only on a rough-barked tree, called Tapiriba, on the
Amazon. It is very abundant, but so exactly does
it resemble the bark in colour and rugosity, and so
closely does it cling to the branches, that until it
moves it is absolutely invisible ! An allied species (0.

RESEMBLANCES AMONG ANIMALS. 57

concentricus) is found only at Para, on a distinct
species of tree, the bark of which it resembles with
equal accuracy. Both these insects are abundant, and
we may fairly conclude that the protection they derive
from this strange concealment is at least one of the
causes that enable the race to flourish.

Many of the species of Cicindela, or tiger beetle,
will illustrate this mode of protection. Our common
Cicindela campestris frequents grassy banks, and is
of a beautiful green colour, while C. maritima, which
is found only on sandy sea- shores, is of a pale bronzy
yellow, so as to be almost invisible. A great number
of the species found by myself in the Malay islands
are similarly protected. The beautiful Cicindela glo-
riosa, of a very deep velvety green colour, was only
taken upon wet mossy stones in the bed of a moun-
tain stream, where it was with the greatest difficulty
detected. A large brown species (C. heros) was found
chiefly on dead leaves in forest paths ; and one which
was never seen except on the wet mud of salt marshes
was of a glossy olive so exactly the colour of the mud
as only to be distinguished when the sun shone, by its
shadow! Where the sandy beach was coralline and
nearly white, I found a very pale Cicindela ; wherever
it was volcanic and black, a dark species of the same
genus was sure to be met with.

There are in the East small beetles of the family
Buprestido3 which generally r3st on the midrib of a
leaf, and the naturalist often hesitates before picking
them off, so closely do they resemble pieces of bird's

58 MIMICRY, AND OTHER PROTECTIVE

dung. Kirby and Spence mention the small beetle
Onthophilus sulcatus as being like the seed of an um-
belliferous plant ; and another small weevil, which is
much persecuted by predatory beetles of the genus
Harpalus, is of the exact colour of loamy soil, and
was found to be particularly abundant in loam pits.
Mr. Bates mentions a small beetle (Chlamys pilula)
which was ^indistinguishable by the eye from the
dung of caterpillars, while some of the Cassidse, from
their hemispherical forms and pearly gold colour, re-
semble glittering dew-drops upon the leaves.

A number of our small brown and speckled weevils
at the approach of any object roll off the leaf they
are sitting on, at the same time drawing in their legs
and antennae, which fit so perfectly into cavities for
their reception that the insect becomes a mere oval
brownish lump, which it is hopeless to look for among
the similarly coloured little stones and earth pellets
among which it lies motionless.

The distribution of colour in butterflies and moths
respectively is very instructive from this point of
view'. The former have all their brilliant colouring on
the upper surface of all four wings, while the under
surface is almost always soberly coloured, and often
very dark and obscure. The moths on the contrary
have generally their chief colour on the hind wings
only, the upper wings being of dull, sombre, and often
imitative tints, and these generally conceal the hind
wings when the insects are in repose. This arrange-
ment of the colours is therefore eminently protective,

RESEMBLANCES AMONG ANIMALS. 59

because the butterfly always rests with his wings raised
so as to conceal the dangerous brilliancy of his upper
surface. It is probable that if we watched their habits
sufficiently we should find the under surface of the
wings of butterflies very frequently imitative and pro-
tective. Mr. T. W. Wood has pointed out that the
little orange-tip butterfly often rests in the evening on
the green and white flower heads of an umbelliferous
plant, and that when observed in this position the beau-
tiful green and white mottling of the under surface
completely assimilates with the flower heads and ren-
ders the creature very difficult to be seen. It is pro-
bable that the rich dark colouring of the under side of
our peacock, tortoiseshell, and red-admiral butterflies
answers a similar purpose.

Two curious South American butterflies that always
settle on the trunks of trees (Gynecia clirce and Calli-
zona acesta) have the under surface curiously striped
and mottled, and when viewed obliquely must closely
assimilate with the appearance of the furrowed bark
of many kinds of trees. But the most wonderful
and undoubted case of protective resemblance in a
butterfly which I have ever seen, is that of the
common Indian Kallima inachis, and its Malayan
ally, Kallima paralekta. The upper surface of these
insects is very striking and showy, as they are of
a large size, and are adorned with a broad band of
rich orange on a deep bluish ground. The under
side is very variable in colour, so that out of fifty
specimens no two can be found exactly alike, but

60 MIMICRY, AND OTHER PROTECTIVE

every one of them will be of some shade of ash or
brown or ochre, such as are found among dead, dry,
or decaying leaves. The apex of the upper wings
is produced into an acute point, a very common form
in the leaves of tropical shrubs and trees, and the
lower wings are also produced into a short narrow
tail. Between these two points runs a dark curved
line exactly representing the midrib of a leaf, and
from this radiate on each side a few oblique lines,
which serve to indicate the lateral veins of a leaf.
These marks are more clearly seen on the outer por-
tion of the base of the wings, and on the inner side
towards the middle and apex, and it is very curious
to observe how the usual marginal and transverse
stria? of the group are here modified and strengthened
so as to become adapted for an imitation of the
venation of a leaf. We come now to a still more
extraordinary part of the imitation, for we find re-
presentations of leaves in every stage of decay,
variously blotched and mildewed and pierced with
holes, and in many cases irregularly covered with
powdery black dots gathered into patches and spots,
so closely resembling the various kinds of minute
fungi that grow on dead leaves that it is impossible
to avoid thinking at first sight that the butterflies
themselves have been attacked by real fungi.

But this resemblance, close as it is, would be of little
use if the habits of the insect did not accord with it.
If the butterfly sat upon leaves or upon flowers, or
opened its wings so as to expose the upper surface, or

RESEMBLANCES AMONG ANIMALS. 61

exposed and moved its head and antenna? as many
other butterflies do, its disguise would be of little
avail. We might be sure, however, from the analogy
of many other cases, that the habits of the insect are
such as still further to aid its deceptive garb ; but
we are not obliged to make any such supposition, since
I myself had the good fortune to observe scores of
Kallima paralekta, in Sumatra, and to capture many
of them, and can vouch for the accuracy of the fol-
lowing details. These butterflies frequent dry forests
and fly very swiftly. They were never seen to settle
on a flower or a green leaf, but were many times lost
sight of in a bush or tree of dead leaves. On such oc-
casions they were generally searched for in vain, for
while gazing intently at the very spot where one had
disappeared, it would often suddenly dart out, and
again vanish twenty or fifty yards further on. On
one or two occasions the insect was detected reposing,
and it could then be seen how completely it assimilates
itself to the surrounding leaves. It sits on a nearly
upright twig, the wings fitting closely back to back,
concealing the antennaB and head, which are drawn up
between their bases. The little tails of the hind wing
touch the branch, and form a perfect stalk to the leaf,
which is supported in its place by the claws of the
middle pair of feet, which are slender and inconspicu-
ous. The irregular outline of the wings gives exactly
the perspective effect of a shrivelled leaf. We thus
have size, colour, form, markings, and habits, all com-
bining together to produce a disguise which may be

62 MIMICRY, AND OTHER PROTECTIVE

said to be absolutely perfect ; and the protection which
it affords is sufficiently indicated by the abundance of
the individuals that possess it.

The Rev. Joseph Greene has called attention to the
striking harmony between the colours of those British
moths which are on the wing in autumn and winter,
and the prevailing tints of nature at those seasons. In
autumn various shades of yellow and brown prevail,
and he shows that out of fifty-two species that fly
at this season, no less than forty-two are of corres-
ponding colours. Orgyia antiqua, 0. gonostigma, the
genera Xanthia, Glsea, and Ennomos are examples. In
winter, gray and silvery tints prevail, and the genus
Chematobia and several species of Hybernia which
fly during this season are of corresponding hues. No
doubt if the habits of moths in a state of nature were
more closely observed, we should find many cases of
special protective resemblance. A few such have al-
ready been noticed. Agriopis aprilina, Acronycta psi,
and many other moths which rest during the day on the
north side of the trunks of trees can with difficulty bo
distinguished from the grey and green lichens that
cover them. The lappet moth (Gastropacha querci)
closely resembles both in shape and colour a brown
dry leaf; and the well-known buff- tip moth, when at
rest is like the broken end of a lichen-covered branch.
There are some of the small moths which exactly re-
semble the dung of birds dropped on leaves, and on this
point Mr. A. Sidgwick, in a paper read before the
Rugby School Natural History Society, gives the

RESEMBLANCES AMONG ANIMALS. 63

following original observation : — " I myself have more
than once mistaken Cilix compressa, a little white and
grey moth, for a piece of bird's dung dropped upon a
leaf, and vice versa the dung for the moth. Bryophila
Glandifera and Perla are the very image of the mortar
walls on which they rest ; and only this summer, in
Switzerland, I amused myself for some time in watch-
ing a moth, probably Larentia tripunctaria, fluttering
about quite close to me, and then alighting on a wall of
the stone of the district which it so exactly matched as
to be quite invisible a couple of yards off." There are
probably hosts of these resemblances which have not
been observed, owing to the difficulty of finding many
of the species in their stations of natural repose. Ca-
terpillars are also similarly protected. Many exactly
resemble in tint the leaves they feed upon ; others are
like little brown twigs, and many are so strangely
marked or humped, that when motionless they can
hardly be taken to be living creatures at all. Mr.
Andrew Murray has remarked how closely the larva of
the peacock moth (Saturnia pavonia-minor) harmonizes
in its ground colour with that of the young buds of
heather on which it feeds, and that the pink spots with
which it is decorated correspond with the flowers and
flower-buds of the same plant.

The whole order of Orthoptera, grasshoppers, locusts,
crickets, &c., are protected by their colours harmoniz-
ing with that of the vegetation or the soil on which
they live, and in no other group have we such strik-
ing examples of special resemblance. Most of the

64 MIMICRY, AND OTHER PROTECTIl^E

tropical Mantidae and Locustidsc are of the exact tint of
the leaves on which they habitually repose, and many
of them in addition have the veinings of their wings
modified so as exactly to imitate that of a leaf. This
is carried to the furthest possible extent in the wonder-
ful genus, Phyllium, the ec walking leaf," in which not
only are the wings perfect imitations of leaves in every
detail, but the thorax and legs. are flat, dilated, and
leaf-like ; so that when the living insect is resting
among the foliage on which it feeds, the closest ob-
servation is often unable to distinguish between the
animal and the vegetable.

O

The whole family of the Phasmidce, or spectres, to
which this insect belongs, is more or less imitative, and
a great number of the species are called " walking-stick
insects," from their singular resemblance to twigs and
branches. Some of these are a foot long and as thick
as one's finger, and their whole colouring, form, rugos-
ity, and the arrangement of the head, legs, and anten-
na?, are such as to render them absolutely identical in
appearance with dead sticks. They hang loosely about
shrubs in the forest, and have the extraordinary habit
of stretching out their legs unsymmetrically, so as to
render the deception more complete. One of these
creatures obtained by myself in Borneo (Ceroxylus
laceratus) was covered over with foliaceous excrescences
of a clear olive green colour, so as exactly to resemble a
stick grown over by a creeping moss or jungermannia.
The Dyak who brought it me assured me it was grown
over with moss although alive, and it was only after a

RESEMBLANCES AMONG ANIMALS. 65

most minute examination that I could convince myself
it was not so.

We need not adduce any more examples to show
how important are the details of form and of colouring
in animals, and that their very existence may often
•depend upon their being by these means concealed from
their enemies. This kind of protection is found appar-
ently in every class and order, for it has been noticed
wherever we can obtain sufficient knowledge of the
details of an animal's life-history. It varies in degree,
from the mere absence of conspicuous colour or a
general harmony with the prevailing tints of nature,
up to such a minute and detailed resemblance to inor-
ganic or vegetable structures as to realize the talisman
of the fairy tale, and to give its possessor the power of
rendering itself invisible.

Theory of Protective Colouring.

We will now endeavour to show how these wonderful
resemblances have most probably been brought about.
Returning to the higher animals, let us consider the
remarkable fact of the rarity of white colouring in the
mammalia or birds of the temperate or tropical zones
in a state of nature. There is not a single white land-
bird or quadruped in Europe, except the few arctic or
alpine species, to which white is a protective colour.
Yet in many of these creatures there seems to be no
inherent tendency to avoid white, for directly they are
domesticated white varieties arise, and appear to thrive
as well as others. We have white mice and rats, white

F

66 MIMICRY, AND OTHER PROTECTIVE

cats, horses, dogs, and cattle, white poultry, pigeons,
turkeys, and ducks, and white rabbits. Some of these
animals have been domesticated for a long period,
others only for a few centuries ; but in almost every
case in which an animal has been thoroughly domesti-
cated, parti-coloured and white varieties are produced
and become permanent.

It is also well known that animals in a state of nature
produce white varieties occasionally. Blackbirds, star-
lings, and crows are occasionally seen white, as well as
elephants, deer, tigers, hares, moles, and many other
animals ; but in no case is a permanent white race
produced. Now there are no statistics to show that
the normal- coloured parents produce white offspring
oftener under domestication than in a state of nature,
and we have no right to make such an assumption if
the facts can be accounted for without it. But if the
colours of animals do really, in the various instances
already adduced, serve for their concealment and pre-
servation, then white or any other conspicuous colour
must be hurtful, and must in most cases shorten an
animal's life. A white rabbit would be more surely the
prey of hawk or buzzard, and the white mole, or field
mouse, could not long escape from the vigilant owl.
So, also, any deviation from those tints best adapted
to conceal a carnivorous animal would render the pur-
suit of its prey much more difficult, would place it at
a disadvantage among its fellows, and in a time of
scarcity would probably cause it to starve to death.
On the other hand, if an animal spreads from a

RESEMBLANCES AMONG- ANIMALS. 67

temperate into an arctic district, the conditions are
changed. During a large portion of the year, and
just when the struggle for existence is most severe,
white is the prevailing tint of nature, and dark colours
will be the most conspicuous. The white varieties will
now have an advantage ; they will escape from their
enemies or will secure food, while their brown com-
panions will be devoured or will starve ; and as " like
produces like" is the established rule in nature, the
white race will become permanently established, and
dark varieties, when they occasionally appear, will soon
die out from their want of adaptation to their environ-
ment. In each case the fittest will survive, and a race
will be eventually produced adapted to the conditions
in which it lives.

We have here an illustration of the simple and effec-
tual means by which animals are brought into harmony
with the rest of nature. That slight amount of varia-
bility in every species, which we often look upon as
something accidental or abnormal, or so insignificant as
to be hardly worthy of notice, is yet the foundation of
all those wonderful and harmonious resemblances which
play such an important part in the economy of nature.
Variation is generally very small in amount, but it
is all that is required, because the change in the
external conditions to which an animal is subject is
generally very slow and intermittent. When these
changes have taken place too rapidly, the result has
often been the extinction of species ; but the general
rule is, that climatal and geological changes go on

F 2

68 MIMICRY, AND OTHER PROTECTIVE

slowly, and the slight but continual variations in the
colour, form, and structure of all animals, has fur-
nished individuals adapted to these changes, and who
have become the progenitors of modified races. Eapid
multiplication, incessant slight variation, and survival
of the fittest — these are the laws which ever keep the
organic world in harmony with the inorganic, and
with itself. These are the laws which we believe have
produced all the cases of protective resemblance already
adduced, as well as those still more curious examples
we have yet to bring before our readers.

It must always be borne in mind that the more won-
derful examples, in which there is not only a general
but a special resemblance — as in the walking leaf, the
mossy phasma, and the leaf-winged butterfly — repre-
sent those few instances in which the process of modi-
fication has been going on during an immense series
of generations. They all occur in the tropics, where
the conditions of existence are the most favourable,
and where climatic changes have for long periods
been hardly perceptible. In most of them favourable
variations both of colour, form, structure, and instinct
or habit, must have occurred to produce the perfect
adaptation we now behold. All these are known to
vary, and favourable variations when not accompanied
by others that were unfavourable, would certainly
survive. At one time a little step might be made in
this direction, at another time in that — a change of
conditions might sometimes render useless that which

O

it had taken ages to produce — great and sudden physi-

RESEMBLANCES AMONG ANIMALS. C9

cal modifications might often produce the extinction
of a race just as it was approaching perfection, and a
hundred checks of which we can know nothing may
have retarded the progress towards perfect adaptation ;
so that we can hardly wonder at there being so few
cases in which a completely successful result has been
attained as shown by the abundance and wide diffusion
of the creatures so protected.

Objection that Colour, as being dangerous, should not exist
in Nature.

It is as well here to reply to an objection that will
no doubt occur to many readers —that if protection is
so useful to all animals, and so easily brought about
by variation and survival of the fittest, there ought
to be no conspicuously-coloured creatures ; and they
will perhaps ask how we account for the brilliant
birds, and painted snakes, and gorgeous insects, that
occur abundantly all over the world. It will be advis-
able to answer this question rather fully, in order that
we may be prepared to understand the phenomena of
" mimicry," which it is the special object of this paper
to illustrate and explain.

The slightest observation of the life of animals will
show us, that they escape from their enemies and
obtain their food in an infinite number of ways ; and
that their varied habits and instincts are in every case
adapted to the conditions of their existence. The
porcupine and the hedgehog have a defensive armour
that saves them from the attacks of most animals.

70 MIMICRY, AND OTHER PROTECTIVE

The tortoise is not injured by the conspicuous colours
of his shell, because that shell is in most cases an effec-
tual protection to him. The skunks of North America
find safety in their power of emitting an unbearably
offensive odour; the beaver in its aquatic habits and
solidly constructed abode. In some cases the chief
danger to an animal occurs at one particular period of
its existence, and if that is guarded against its numbers
can easily be maintained. This is the case with many
birds, the eggs and young of which are especially ob-
noxious to clanger, and we find accordingly a variety
of curious contrivances to protect them. "We have
nests carefully concealed, hung from the slender extre-
mities of grass or boughs over water, or placed in the
hollow of a tree with a very small opening. When
these precautions are successful, so many more indivi-
duals will be reared than can possibly find food during
the least favourable seasons, that there will always be a
number of weakly and inexperienced young birds who
will fall a prey to the enemies of the race, and thus
render necessary for the stronger and healthier indi-
viduals no other safeguard than their strength and
activity. The instincts most favourable to the produc-
tion and rearing of offspring will in these cases be
most important, and the survival of the fittest will act
so as to keep up and advance those instincts, while
other causes which tend to modify colour and marking
may continue their action almost unchecked.

It is perhaps in insects that we may best study the
varied means by which animals are defended or con-

RESEMBLANCES AMONG ANIMALS. 71

cealed. One of the uses of the phosphorescence with
which many insects are furnished, is probably to
frighten away their enemies ; for Kirby and Spence
state that a ground beetle (Carabus) has been observed
running round and round a luminous centipede as if
afraid to attack it. An immense number of insects
have stings, and some stingless ants of the genus Poly-
rachis are armed with strong and sharp spines on the
back, which must render them unpalatable to many of
the smaller insectivorous birds. Many beetles of the
family Curculionidse have the wing cases and other ex-
ternal parts so excessively hard, that they cannot be
pinned without first drilling a hole to receive the pin,
and it is probable that all such find a protection in
this excessive hardness. Great numbers of insects hide
themselves among the petals of flowers, or in the cracks
of bark and timber ; and finally, extensive groups and
even whole orders have a more or less powerful and
disgusting smell and taste, which they either possess
permanently, or can emit at pleasure. The attitudes of
some insects may also protect them, as the habit of
turning up the tail by the harmless rove-beetles (Sta-
phylindidaa) no doubt leads other animals besides chil-
dren to the belief that they can sting. The curious
attitude assumed by sphinx caterpillars is probably a
safeguard, as well as the blood-red tentacles which
can suddenly be thrown out from the neck, by the
caterpillars of all the true swallow-tailed butterflies.

It is among the groups that possess some of these
varied kinds of protection in a high degree, that we

72 MIMICRY, AND OTHER PROTECTIVE

find the greatest amount of conspicuous colour, or at
least the most complete absence of protective imitation.
The stinging Hymenoptera, wasps, bees, and hornets,
are, as a rule, very showy and brilliant insects, and
there is not a single instance recorded in which any one
of them is coloured so as to resemble a vegetable or in-
animate substance. The Chrysididse, or golden wasps,
which do not sting, possess as a substitute the power of
rolling themselves up into a ball, which is almost as
hard and polished as if really made of metal, — and they
are all adorned with the most gorgeous colours. The
whole order Hemiptera (comprising the bugs) emit a
powerful odour, and they present a very large propor-
tion of gay -coloured and conspicuous insects. The
lady-birds (Coccinellidas) and their allies the Eu-
morphida?, are often brightly spotted, as if to attract
attention ; but they can both emit fluids of a very
disagreeable nature, they are certainly rejected by
some birds, and are probably never eaten by any.

The great family of ground beetles (Carabidse)
almost all possess a disagreeable and some a very
pungent smell, and a few, called bombardier beetles,
have the peculiar faculty of emitting a jet of very
volatile liquid, which appears like a puff of smoke,
and is accompanied by a distinct crepitating explosion.
It is probably because these insects are mostly nocturnal
and predacious that they do not present more vivid hues.
They are chiefly remarkable for brilliant metallic tints
or dull red patches when they are not wholly black,
and are therefore very conspicuous by day, when insect-

RESEMBLANCES AMONG- ANIMALS. 73

eaters are kept off by their bad odour and taste, but
are sufficiently invisible at night when it is of impor-
tance that their prey should not become aware of their
proximity.

It seems probable that in some cases that which
would appear at first to be a source of danger to its
possessor may really be a means of protection. Many
showy and weak -fly ing butterflies have a very broad
expanse of wing, as in the brilliant blue Morphos of
Brazilian forests, and the large Eastern Papilios ; yet
these groups are tolerably plentiful. Now, specimens
of these butterflies are often captured with pierced and
broken wings, as if they had been seized by birds from
whom they had escaped ; but if the wings had been
much smaller in proportion to the body, it seems pro-
bable that the insect would be more frequently struck
or pierced in a vital part, and thus the increased ex-
panse of the wings may have been indirectly beneficial.

In other cases the capacity of increase in a species is
so great that however many of the perfect insect may
be destroyed, there is always ample means for the con-
tinuance of the race. Many of the flesh flies, gnats,
ants, palm-tree weevils and locusts are in this cate-
gory. The whole family of Cetoniadas or rose chafers,
so full of gaily-coloured species, are probably saved
from attack by a combination of characters. They fly
very rapidly with a zigzag or waving course ; they hide
themselves the moment they alight, either in the corolla
of flowers, or in rotten wood, or in cracks and hollows
of trees, and they are generally encased in a very hard

74 MIMICRY, AND OTHER PROTECTIVE

and polished coat of mail which may render them
unsatisfactory food to such birds as would be able to
capture them. The causes which lead to the develop-
ment of colour have been here able to act unchecked,
and we see the result in a large variety of the most
gorgeously-coloured insects.

Here, then, with our very imperfect knowledge of
the life-history of animals, we are able to see that
there are widely varied modes by which they may
obtain protection from their enemies or concealment
from their prey. Some of these seem to be so com-
plete and effectual as to answer all the wants of the
race, and lead to the maintenance of the largest pos-
sible population. When this is the case, we can well
understand that no further protection derived from a
modification of colour can be of the slightest use, and
the most brilliant hues may be developed without any
prejudicial effect upon the species. On some of the
laws that determine the development of colour some-
thing may be said presently. It is now merely neces-
sary to show that concealment by obscure or imitative
tints is only one out of very many ways by which
animals maintain their existence ; and having done
this we are prepared to consider the phenomena of
what has been termed " mimicry." It is to be par-
ticularly observed, however, that the word is not here
used in the sense of voluntary imitation, but to imply
a particular kind of resemblance — a resemblance not in
internal structure but in external appearance — a resem-
blance in those parts only that catch the eye — a re-

RESEMBLANCES AMONG ANIMALS. 75

semblance that deceives. As this kind of resemblance
has the same effect as voluntary imitation or mimicry,
and as we have no word that expresses the required
meaning, " mimicry " was adopted by Mr. Bates (who
was the first to explain the facts), and has led to
some misunderstanding ; but there need be none, if
it is remembered that both a mimicry " and a imita-
tion" are used in a metaphorical sense, as implying
that close external likeness which causes things un-
like in structure to be mistaken for each other.

Mimicry.

It has been long known to entomologists that certain
insects bear a strange external resemblance to others
belonging to distinct genera, families, or even orders,
and with which they have no real affinity whatever.
The fact, however, appears to have been generally con-
sidered as dependent upon some unknown law of " ana-
logy " — some " system of nature," or "general plan,"
which had guided the Creator in designing the myriads
of insect forms, and which we could never hope to
understand. In only one case does it appear that the
resemblance was thought to be useful, and to have been
designed as a means to a definite and intelligible
purpose. The flies of the genus Volucella enter the
nests of bees to deposit their eggs, so that their larvae
may feed upon the larvse of the bees, and these flies
are each wonderfully like the bee on which it is
parasitic. Kirby and Spence believed that this resem-
blance or " mimicry " was for the express purpose of

7G MIMICRY, AND OTHER PROTECTIVE

protecting the flies from the attacks of the bees, and
the connection is so evident that it was hardly possible
to avoid this conclusion. The resemblance, however,
of moths to butterflies or to bees, of beetles to wasps,
and of locusts to beetles, has been many times noticed
by eminent writers ; but scarcely ever till within the
last few years does it appear to have been considered
that these resemblances had any special purpose, or
were of any direct benefit to the insects themselves.
In this respect they were looked upon as accidental,
as instances of the " curious analogies " in nature
which must be wondered at but which could not be ex-
plained. Recently, however, these instances have been
greatly multiplied; the nature of the resemblances
has been more carefully studied, and it has been found
that they are often carried out into such details as
almost to imply a purpose of deceiving the observer.
The phenomena, moreover, have been shown to •follow
certain definite laws, which again all indicate their
dependence on the more general law of the " survival
of the fittest," or " the preservation of favoured races
in the struggle for life." It will, perhaps, be as well
here to state what these laws or general conclusions
are, and then to give some account of the facts which
support them.

The first law is, that in an overwhelming majority of
cases of mimicry, the animals (or the groups) which
resemble each other inhabit the same country, the same
district, and in most cases are to be found together
on the very same spot.

RESEMBLANCES AMONG ANIMALS. 77

The second law is, that these resemblances are not
indiscriminate, but are limited to certain groups, which
in every case are abundant in species and individuals,
and can often be ascertained to have some special
protection.

The third law is, that the species which resemble
or " mimic " these dominant groups, are comparatively
less abundant in individuals, and are often very rare.

These laws will be found to hold good, in all the
cases of true mimicry among various classes of animals
to which we have now to call the attention of our
readers.

Mimicry among Lepidoptera.

As it is among butterflies that instances of mimicry
are most numerous and most striking, an account of
some of the more prominent examples in this group will
first be given. There is in South America an extensive
family of these insects, the Heliconids3, which are in
many respects very remarkable. They are so abundant
and characteristic in all the woody portions of the
American tropics, that in almost every locality they
will be seen more frequently than any other butterflies.
They are distinguished by very elongate wings, body,
and antennce, and are exceedingly beautiful and varied
in their colours ; spots and patches of yellow, red, or
pure white upon a black, blue, or brown ground, being
most general. They frequent the forests chiefly, and all
fly slowly and weakly; yet although they are so conspi-
cuous, and could certainly be caught by insectivorous

78 MIMICRY, AND OTHER PROTECTIVE

birds more easily than almost any other insects, their
great abundance all over the wide region they inhabit
shows that they are not so persecuted. It is to be es-
pecially remarked also, that they possess no adaptive
colouring to protect them during repose, for the under
side of their wings presents the same, or at least an
equally conspicuous colouring as the upper side ; and
they may be observed after sunset suspended at the end
of twigs and leaves where they have taken up their
station for the night, fully exposed to the attacks of
enemies if they have any. These beautiful insects
possess, however, a strong pungent semi-aromatic or
medicinal odour, which seems to pervade all the juices
of their system. When the entomologist squeezes the
breast of one of them between his fingers to kill it, a
yellow liquid exudes which stains the skin, and the
smell of which can only be got rid of by time and re-
peated washings. Here we have probably the cause of
their immunity from attack, since there is a great deal
of evidence to show that certain insects are so disgust-
ing to birds that they will under no circumstances
touch them. Mr. Stainton has observed that a brood
of young turkeys greedily devoured all the worthless
moths he had amassed in a night's "sugaring," yet
one after another seized and rejected a single white
moth which happened to be among them. Young phea-
sants and partridges which eat many kinds of cater-
pillars seem to have an absolute dread of that of the
common currant moth, which they will never touch, and
tomtits as well as other small birds appear never to eat

•RESEMBLANCES AMONG ANIMALS. 79

the same species. In the case of the Heliconidse, how-
ever, we have some direct evidence to the same effect.
In the Brazilian forests there are great numbers of in-
sectivorous birds — as jacamars, trogons, and puffbirds
— which catch insects on the wing, and that they de-
stroy many butterflies is indicated by the fact that the
wings of these insects are often found on the ground
where their bodies have been devoured. But among
these there are no wings of Heliconidse, while those
of the large showy Nymphalidse, which have a much
swifter flight, are often met with. Again, a gentleman
who had recently returned from Brazil stated at a meet-
ing of the Entomological Society that he once observed
a pair of puffbirds catching butterflies, which they
brought to their nest to feed their young ; yet during
half an hour they never brought one of the Heliconidse,
which were flying lazily about in great numbers, and
which they could have captured more easily than any
others. It was this circumstance that led Mr. Belt to
observe them so long, as he could not understand why
the most common insects should be altogether passed
by. Mr. Bates also tells us that he never saw them
molested by lizards or predacious flies, which often
pounce on other butterflies.

If, therefore, we accept it as highly probable (if not
proved) that the Heliconidse are very greatly protected
from attack by their peculiar odour and taste, we find it
much more easy to understand their chief characteristics
— their great abundance, their slow flight, their gaudy
colours, and the entire absence of protective tints on

80 MIMICRY, AND OTHER PROTECTIVE

their under surfaces. This property places them some-
what in the position of those curious wingless birds of
oceanic islands, the dodo, the apteryx, and the moas,
which are with great reason supposed to have lost the
power of flight on account of the absence of carnivorous
quadrupeds. Our butterflies have been protected in a
different way, but quite as effectually ; and the result
has been that as there has been nothing to escape from,
there has been no weeding out of slow flyers, and as
there has been nothing to hide from, there has been no
extermination of the bright-coloured varieties, and no
preservation of such as tended to assimilate with sur-
rounding objects.

Now let us consider how this kind of protection must
act. Tropical insectivorous birds very frequently sit on
dead branches of a lofty tree, or on those which overhang
forest paths, gazing intently around, and darting off at
intervals to seize an insect at a considerable distance,
which they generally return to their station to devour.
If a bird began by capturing the slow-flying, conspicuous
Heliconidse, and found them always so disagreeable that
it could not eat them, it would after a very few trials
leave off catching them at all ; and their whole appear-
ance, form, colouring, and mode of flight is so peculiar,
that there can be little doubt birds would soon learn to
distinguish them at a long distance, and never waste
any time in pursuit of them. Under these circumstances,
it is evident that any other butterfly of a group which
birds were accustomed to devour, would be almost
equally well protected by closely resembling a Heliconia

RESEMBLANCES AMONG ANIMALS. 81

externally, as if it acquired also the disagreeable odour ;
always supposing that there were only a few of them
among a great number of the Heliconias. If the birds
could not distinguish the two kinds externally, and
there were on the average only one eatable among
fifty uneatable, they would soon give up seeking for
the eatable ones, even if they knew them to exist. If,
on the other hand, any particular butterfly of an eatable
group acquired the disagreeable taste of the Heliconias
while it retained the characteristic form and colouring
of its own group, this would be really of no use to it
whatever ; for the birds would go on catching it among
its eatable allies (compared with which it would rarely
occur), it would be wounded and disabled, even if re-
jected, and its increase would thus be as effectually
checked as if it were devoured. It is important, there-
fore, to understand that if any one genus of an extensive
family of eatable butterflies were in danger of extermi-
nation from insect-eating birds, and if two kinds of
variation were going on among them, some individuals
possessing a slightly disagreeable taste, others a slight
resemblance to the Heliconida?, this latter quality would
be much more valuable than the former. The change
in flavour would not at all prevent the variety from
being captured as before, and it would almost certainly
be thoroughly disabled before being rejected. The ap-
proach in colour and form to the HeliconidaB, however,
would be at the very first a positive, though perhaps a
slight advantage ; for although at short distances this
variety would be easily distinguished and devoured, yet

G

82 MIMICRY, AND OTHER PROTECTIVE

at a longer distance it might be mistaken for one of the
uneatable group, and so be passed by and gain another
day's life, which might in many cases be sufficient
for it to lay a quantity of eggs and leave a numerous
progeny, many of which would inherit the peculiarity
which had been the safeguard of their parent.

Now, this hypothetical case is exactly realized in
South America. Among the white butterflies forming
the family Pieridse (many of which do not greatly
differ in appearance from our own cabbage butterflies)
is a genus of rather small size (Leptalis), some species
of which are white like their allies, while the larger
number exactly resemble the Heliconidse in the form
and colouring of the wings. It must always be re-
membered that these two families are as absolutely dis-
tinguished from each other by structural characters as
are the carnivora and the ruminants among quadrupeds,
and that an entomologist can always distinguish the one
from the other by the structure of the feet, just as
certainly as a zoologist can tell a bear from a buffalo
by the skull or by a tooth. Yet the resemblance of a
species of the one family to another species in the other
family was often so great, that both Mr. Bates and my-
self were many times deceived at the time of capture,
and did not discover the distinctness of the two insects
till a closer examination detected their essential differ-
ences. During his residence of eleven years in the
Amazon valley, Mr. Bates found a number of species
or varieties of Leptalis, each of which was a more or
less exact copy of one of the Heliconidoe of the district

RESEMBLANCES AMONG- ANIMALS. S3

it inhabited ; and the results of his observations arc
embodied in a paper published in the Linnean Trans-
actions, in which he first explained the phenomena of
" mimicry " as the result of natural selection, and
showed its identity in cause and purpose with protec-
tive resemblance to vegetable or inorganic forms.

The imitation of the HeliconidaB by the Leptalides
is carried out to a wonderful degree in form as well as
in colouring. The wings have become elongated to the
same extent, and the antenna? and abdomen have both
become lengthened, to correspond with the unusual
condition in which they exist in the former family.
In colouration there are several types in the different
genera of Heliconid^e. The genus Mechanitis is gene-
rally of a rich semi-transparent brown, banded with
black and yellow ; Methona is of large size, the wings
transparent like horn, and with black transverse bands ;
while the delicate Ithomias are all more or less trans-
parent, with black veins and borders, and often with
marginal and transverse bands of orange red. These
different forms are all copied by the various species
of Leptalis, every band and spot and tint of colour,
and the various degrees of transparency, being exactly
reproduced. As if to derive all the benefit possible
from this protective mimicry, the habits have become
so modified that the Leptalides generally frequent the
very same spots as their models, and have the same
mode of flight; and as they are always very scarce
(Mr. Bates estimating their numbers at about one to a
thousand of the group they resemble), there is hardly a

G 2

84 MIMICRY, AND OTHER PROTECTIVE

possibility of their being found out by their enemies.
It is also very remarkable that in almost every case the
particular Ithomias and other species of Heliconida3
which they resemble, are noted as being very common
species, swarming in individuals, and found over a
wide range of country. This indicates antiquity and
permanence in the species, and is exactly the condition
most essential both to aid in the development of the
resemblance, and to increase its utility.

But the Leptalides are not the only insects who have
prolonged their existence by imitating the great pro-
tected group of Heliconidse ; — a genus of quite another
family of most lovely small American butterflies, the
Erycinidse, and three genera of diurnal moths, also
present species which often mimic the same dominant
forms, so that some, as Ithomia ilerdina of St. Paulo,
for instance, have flying with them a few individuals
of three widely different insects, which are yet dis-
guised with exactly the same form, colour, and mark-
ings, so as to be quite undistinguishable when upon the
wing. Again, the Heliconidse are not the only group
that are imitated, although they are the most frequent
models. The black and red group of South American
Papilios, and the handsome Erycinian genus Stalachtis,
have also a few who copy them ; but this fact offers no
difficulty, since these two groups are almost as domi-
nant as the Heliconidse. They both fly very slowly,
they are both conspicuously coloured, and they both
abound in individuals ; so that there is every reason to
believe that they possess a protection of a similar kind

RESEMBLANCES AMONG ANIMALS. 85

to the Heliconida3, and that it is therefore equally an
advantage to other insects to be mistaken for them.

O

There is also another extraordinary fact that we are
not yet in a position clearly to comprehend : some
groups of the Heliconida3 themselves mimic other
groups. Species of Heliconia mimic Mechanitis, and
every species of Napeogenes mimics some other Heli-
conideous butterfly. This would seem to indicate that
the distasteful secretion is not produced alike by all
members of the family, and that where it is deficient
protective imitation comes into play. It is this, per-
haps, that has caused such a general resemblance
among the HeliconidaB, such a uniformity of type with
great diversity of colouring, since any aberration
causing an insect to cease to look like one of the family
would inevitably lead to its being attacked, wounded,
and exterminated, even although it was not eatable.
In other parts of the world an exactly parallel series
of facts have been observed. The Danaidas and the
Acrseidse of the Old World tropics form in fact one
great group with the HeliconidaB. They have the same
general form, structure, -and habits: they possess the
same protective odour, and are equally abundant in
individuals, although not so varied in colour, blue and
white spots on a black ground being the most general
pattern. The insects which mimic these are chiefly
Papilios, and Diadema, a genus allied to our peacock
and tortoiseshell butterflies. In tropical Africa there is
a peculiar group of the genus Danais, characterized
by dark-brown and bluish-white colours, arranged in

o6 MIMICRY, AXD OTHER PROTECTIVE

bands or stripes. One of these, Danais niavius, is
exactly imitated both by Papilio hippocoon and by
Diadema anthedon ; another, Danais echeria, by Pa-
pilio cenea ; and in Natal a variety of the Danais is
found having a white spot at the tip of wings, accom-
panied by a variety of the Papilio bearing a corre-
sponding white spot. Acrsea gea is copied in its very
peculiar style of colouration by the female of Papilio
cynorta, by Panopaaa hirce, and by the female of Elym-
nias phegea. Acrsea euryta of Calabar has a female
variety of Panopea hirce from the same place which
exactly copies it ; and Mr. Trimen, in his paper on
Mimetic Analogies among African Butterflies, published
in the Transactions of the Linnsean Society for 1868,
gives a list of no less than sixteen species and varieties
of Diadema and its allies, and ten of Papilio, which in
their colour and markings are perfect mimics of species
or varieties of Danais or Acrsea which inhabit the same
districts.

Passing on to India, we have Danais tytia, a butter-
fly with semi-transparent bluish wings and a border of
rich reddish brown. This remarkable style of colour-
ing is exactly reproduced in Papilio agestor and in
Diadema nama, and all three insects not unfrequently
come together in collections made at Darjeeling. In
the Philippine Islands the large and curious Idea
leuconoe with its semi-transparent white wings, veined
and spotted with black, is copied by the rare Papilio
idasoides from the same islands.

In the Malay archipelago the very common and

RESEMBLANCES AMONG ANIMALS. 87

beautiful Euplaea miclamus is so exactly mimicked by
two rare Papilios (P. paradoxa and P. senigma) that I
generally caught them under the impression that they
were the more common species ; and the equally com-
mon and even more beautiful Euplaea rhadamanthus,
with its pure white bands and spots on a ground of
glossy blue and black, is reproduced in the Papilio
caunus. Here also there are species of Diadema imi-
tating the same group in two or three instances ; but
we shall have to adduce these further on in connexion
with another branch of the subject.

It has been already mentioned that in South America
there is a group of Papilios which have all the char-
acteristics of a protected race, and whose peculiar
colours and markings are imitated by other butterflies
not so protected. There is just such a group also in
the East, having very similar colours and the same
habits, and these also are mimicked by other species
in the same genus not closely allied to them, and also
by a few of other families. Papilio hector, a common
Indian butterfly of a rich black colour spotted with
crimson, is so closely copied by Papilio romulus, that
the latter insect has been thought to be its female. A
close examination shows, however, that it is essentially
different, and belongs to another section of the genus.
Papilio antiphus and P. diphilus, black swallow-tailed
butterflies with cream-coloured spots, are so well imi-
tated by varieties of P. theseus, that several writers
have classed them as the same species. Papilio liris,
found only in the island of Timor, is accompanied

88 MIMICRY, AND OTHER PROTECTIVE

there by P. senomaus, the female of which so exactly
resembles it that they can hardly be separated in the
cabinet, and on the wing are quite undistinguishable.
But one of the most curious cases is the fine yellow-
spotted Papilio coon, which is unmistakeably imitated
by the female tailed form of Papilio memnon. These
are both from Sumatra ; but in North India P. coon
is replaced by another species, which has been named
P. doubledayi, having red spots instead of yellow ;
and in the same district the corresponding female
tailed form of Papilio androgeus, sometimes considered
a variety of P. memnon, is similarly red-spotted. Mr.
Westwood has described some curious day-flying moths
(Epicopeia) from North India, which have the form
and colour of Papilios of this section, and two of these
are very good imitations of Papilio polydorus and
Papilio varuna, also from North India.

Almost all these cases of mimicry are from the
tropics, where the forms of life are more abundant,
and where insect development especially is of unchecked
luxuriance ; but there are also one or two instances in
temperate regions. In North America, the large and
handsome red and black butterfly Danais erippus is
very common ; and the same country is inhabited by
Limenitis archippus, which closely resembles the
Danais, while it differs entirely from every species of
its own genus.

The only case of probable mimicry in our own coun-
try is the following : — A very common white moth
CSpilosoma menthastri) was found by Mr. Staintoa

RESEMBLANCES AMONG- ANIMALS. 89

to be rejected by young turkeys among hundreds of
other moths on which they greedily fed. Each bird in
succession took hold of this moth and threw it down
again, as if too nasty to eat. Mr. Jenner Weir also
found that this moth was refused by the Bullfinch,
Chaffinch, Yellow Hammer, and Red Bunting, but
eaten after much hesitation by the Robin. We may
therefore fairly conclude that this species would be dis-
agreeable to many other birds, and would thus have an
immunity from attack, which may be the cause of its
great abundance and of its conspicuous white colour.
Now it is a curious thing that there is another moth,
Diaphora mendica, which appears about the same time,
and whose female only is white. It is about the same
size as Spilosoma menthastri, and sufficiently resembles
it in the dusk, and this moth is much less common. It
seems very probable, therefore, that these species stand
in the same relation to each other as the mimicking
butterflies of various families do to the Heliconida3 and
Danaidse. It would be very interesting to experiment
on all white moths, to ascertain if those which are
most common are generally rejected by birds. It may
be anticipated that they would be so, because white
is the most conspicuous of all colours for nocturnal in-
sects, and had they not some other protection would
certainly be very injurious to them.

Lepidoptera mimicking oilier Insects.
In the preceding cases we have found Lepidoptera
imitating other species of the same order, and such

90 MIMICRY, AND OTHER PROTECTIVE

species only as we have good reason to believe were free
from the attacks of many insectivorous creatures ; but
there are other instances in which they altogether lose
the external appearance of the order to which they be-
long, and take on the dress of bees or wasps — insects
which have an undeniable protection in their stings.
The Sesiidse and jiEgeriidas, two families of day-flying
moths, are particularly remarkable in this respect, and
a mere inspection of the names given to the various
species shows how the resemblance has struck every-
one. We have apiformis, vespiforme, ichneumoni-
forme, scoliasforme, sphegiforme (bee-like, wasp-like,
ichneumon-like, &c.) and many others, all indicating a
resemblance to stinging Hymenoptera. In Britain we
may particularly notice Sesia bombiliformis, which very
closely resembles the male of the large and common
humble bee, Bombus hortorum ; Sphecia craboni-
forme, which is coloured like a hornet, and is (on
the authority of Mr. Jenner Weir) much more like it
when alive than when in the cabinet, from the way in
which it carries its wings ; and the currant clear-wing,
Trochilium tipuliforme, which resembles a small black
wasp (Odynerus sinuatus) very abundant in gardens at
the same season. It has been so much the practice to
look upon these resemblances as mere curious analogies
playing no part in the economy of nature, that we have
scarcely any observations of the habits and appearance
when alive of the hundreds of species of these groups
in various parts of the world, or how far they are ac-
companied by Hymenoptera, which they specifically

RESEMBLANCES AMONG- ANIMALS. 91

resemble. There are many species in India (like those
figured by Professor Westwood in his " Oriental Ento-
mology ") which have the hind legs very broad and
densely hairy, so as exactly to imitate the brush-legged
bees (Scopulipedes) which abound in the same country.
In this case we have more than mere resemblance of
colour, for that which is an important functional struc-
ture in the one group is imitated in another whose
habits render it perfectly useless.

Mimicry among Beetles.

It may fairly be expected that if these imitations of
one creature by another really serve as a protection
to weak and decaying species, instances of the same
kind will be found among other groups than the Le-
pidoptera ; and such is the case, although they are
seldom so prominent and so easily recognised as those
already pointed out as occurring in that order. A few
very interesting examples may, however, be pointed out
in most of the other orders of insects. The Coleop-
tera or beetles that imitate other Coleoptera of distinct
groups are very numerous in tropical countries, and
they generally follow the laws already laid down as
regulating these phenomena. The insects which others
imitate always have a special protection, which leads
them to be avoided as dangerous or uneatable by small
insectivorous animals ; some have a disgusting taste
(analogous to that of the Heliconidae) ; others have
such a hard and stony covering that they cannot be
crushed or digested ; while a third set are very active,

92 MIMICRY, AND OTHER PROTECTIVE

and armed with powerful jaws, as well as having some
disagreeable secretion. Some species of Eumorphidae
and Hispidae, small flat or hemispherical beetles which
are exceedingly abundant, and have a disagreeable se-
cretion, are imitated by others of the very distinct
group of Longicornes (of which our common musk-
beetle may be taken as an example). The extraordi-
nary little Cyclopeplus batesii, belongs to the same
sub-family of this group as the Onychocerus scorpio
and 0. concentricus, which have already been adduced
as imitating with such wonderful accuracy the bark
of the trees they habitually frequent ; but it differs
totally in outward appearance from every one of its
allies, having taken upon itself the exact shape and
colouring of a globular Corynomalus, a little stinking
beetle with clubbed antennae. It is curious to see how
these clubbed antennae are imitated by an insect be-
longing to a group with long slender antennae. The
sub-family Anisocerinae, to which Cyclopeplus belongs,
is characterised by all its members possessing a little
knob or dilatation about the middle of the antenna?.
This knob is considerably enlarged in C. batesii, and
the terminal portion of the antennas beyond it is so
small and slender as to be scarcely visible, and thus an
excellent substitute is obtained for the short clubbed
antennas of the Corynomalus. Erythroplatis corallifer
is another curious broad flat beetle, that no one would
take for a Longicorn, since it almost exactly resembles
Cephalodonta spinipes, one of the commonest of the
South American Hispidae ; and what is still more

RESEMBLANCES AMONG- ANIMALS. 93

remarkable, another Longicorn of a distinct group,
Streptolabis hispoicles, was found by Mr. Bates, which
resembles the same insect with equal minuteness, — a
case exactly parallel to that among butterflies, where
species of two or three distinct groups mimicked the
same Heliconia. Many of the soft -winged beetles
( Malacoderms ) are excessively abundant in indivi-
duals, and it is probable that they have some similar
protection, more especially as other species often strik-
ingly resemble them. A Longicorn beetle, Psecilo-
derma terminale, found in Jamaica, is coloured exactly
in the same way as a Lycus (one of the Malacoderms)
from the same island. Eroschema poweri, a Longicorn
from Australia, might certainly be taken for one of
the same group, and several species from the Malay
Islands are equally deceptive. In the Island of Celebes
I found one of this group, having the whole body and
elytra of a rich deep blue colour, with the head only
orange ; and in company with it an insect of a totally
different family (Eucnemidae) with identically the same
colouration, and of so nearly the same size and form
as to completely puzzle the collector on every fresh
occasion of capturing them. I have been recently in-
formed by Mr. Jenner Weir, who keeps a variety of
small birds, that none of them will touch our com-
mon fC soldiers and sailors " (species of Malacoderms),
thus confirming my belief that they were a protected
group, founded on the fact of their being at once very
abundant, of conspicuous colours, and the objects of
mimicry.

94 MIMICRY, AND OTHER PROTECTIVE

There are a number of the larger tropical weevils
which have the elytra and the whole covering of the
body so hard as to be a great annoyance to the entomo-
logist, because in attempting to transfix them the points
of his pins are constantly turned. I have found it ne-
cessary in these cases to drill a hole very carefully with
the point of a sharp penknife before attempting to insert
a pin. Many of the fine long-antennsed AnthribidaB (an
allied group) have to be treated in the same way. We
can easily understand that after small birds have in vain
attempted to eat these insects, they should get to know
them by sight, and ever after leave them alone, and it
will then be an advantage for other insects which are
comparatively soft and eatable, to be mistaken for them.
We need not be surprised, therefore, to find that there
are many Longicorns which strikingly resemble the
"hard beetles " of their own district. In South Brazil,
Acanthotritus dorsalis is strikingly like a Curculio of the
hard genus Heiliplus, and Mr. Bates assures me that he
found Grymnocerus cratosomoides (a Longicorn) on the
same tree with a hard Cratosomus (a weevil), which it
exactly mimics. Again, the pretty Longicorn, Phacel-
locera batesii, mimics one of the hard Anthribidse of the
genus Ptychoderes, having long slender antenna. In
the Moluccas we find Cacia anthriboides, a small Longi-
corn which might be easily mistaken for a very common
species of Anthribidse found in the same districts ; and
the very rare Capnolymma stygium closely imitates the
common Mecocerus gazella, which abounded where it
was taken. Doliops curculionoides and other allied'

RESEMBLANCES AMONG ANIMALS. 95

Longicorns from the Philippine Islands most curiously
resemble, both in form and colouring, the brilliant
Pachyrhynchi, — Curculionidas, which are almost pecu-
liar to that group of islands. The remaining family of
Coleoptera most frequently imitated is the Cicindelida?.
The rare and curious Longicorn, Colly rodes lacordairei,
has exactly the form and colouring of the genus Collyris,
while an undescribed species of Heteromera is exactly
like a Therates, and was taken running on the trunks
of trees, as is the habit of that group. There is one
curious example of a Longicorn mimicking a Longicorn,
like the Papilios and Heliconidse which mimic their
own allies. Agnia fasciata, belonging to the sub-family
Hypselominae, and Nemophas grayi, belonging to the
Lamiinse, were taken in Amboyna on the same fallen
tree at the same time, and were supposed to be the same
species till they were more carefully examined, and
found to be structurally quite different. The colouring
of these insects is very remarkable, being rich steel-blue
black, crossed by broad hairy bands of orange buff, and
out of the many thousands of known species of Longi-
corns they are probably the only two which are so
coloured. The Nemophas grayi is the larger, stronger,
and better armed insect, and belongs to a more widely
spread and dominant group, very rich in species and
individuals, and is therefore most probably the subject
of mimicry by the other species.

Beetles mimicking other Insects.
We will now adduce a few cases in which beetles

96 MIMICRY, AND OTHER PROTECTIVE

imitate other insects, and insects of other orders imi-
tate beetles.

Charis melipona, a South American Longicorn of
the family Necydalidse, has been so named from its
resemblance to a small bee of the genus Melipona.
It is one of the most remarkable cases o^ mimicry,
since the beetle has the thorax and body densely hairy
like the bee, and the legs are tufted in a manner most
unusual in the order Coleoptera. Another Longicorn,
Odontocera ody nereides, has the abdomen banded with
yellow, and constricted at the base, and is altogether
so exactly like a small common wasp of the genus Ody-
nerus, that Mr. Bates informs us he was afraid to take it
out of his net with his fingers for fear of being stung.
Had Mr. Bates's taste for insects been less omnivorous
than it was, the beetle's disguise might have saved it
from his pin, as it had no doubt often done from the
beak of hungry birds. A larger insect, Sphecomorpha
chalybea, is exactly like one of the large metallic blue
wasps, and like them has the abdomen connected with
the thorax by a pedicel, rendering the deception most
complete and striking. Many Eastern species of Lon-
gicorns of the genus Oberea, when on the wing ex-
actly resemble Tenthredinidae, and many of the small
species of Hesthesis run about on timber, and cannot
be distinguished from ants. There is one genus of
South American Longicorns that appears to mimic
the shielded bugs of the genus Scutellera. The Gym-
nocerous capucinus is one of these, and is very
like Pachyotris fabricii, one of the Scutelleridae. The

RESEMBLANCES AMONG ANIMALS. 97

beautiful Gymnocerous dulcissimus is also very like
the same group of insects, though there is no known
species that exactly corresponds to it ; but this is not
to be wondered at, as the tropical Hemiptera have
been comparatively so little cared for by collectors.

Insects mimicking Species of other Orders.

The most remarkable case of an insect of another
order mimicking a beetle is that of the Condylodera
tricondyloides, one of the cricket family from the Phi-
lippine Islands, which is so exactly like a Tricondyla
(one of the tiger beetles), that such an experienced
entomologist as Professor Westwood placed it among
them in his cabinet, and retained it there a long time
before he discovered his mistake ! Both insects run
along the trunks of trees, and whereas Tricondylas are
very plentiful, the insect that mimics it is, as in all
other cases, very rare. Mr. Bates also informs us that
he found at Santarem on the Amazon, a species of
locust which mimicked one of the tiger beetles of the
genus Odontocheila, and was found on the same trees
which they frequented.

There are a considerable number of Diptera, or two-
winged flies, that closely resemble wasps and bees,
and no doubt derive much benefit from the whole-
some dread which those insects excite. The Midas
dives, and other species of large Brazilian flies, have
dark wings and metallic blue elongate bodies, resem-
bling the large stinging Sphegidae of the same coun-
try; and a very large fly of the genus Asilus has

H

98 MIMICRY, AND OTHER PROTECTIVE

black-banded wings and the abdomen tipped with rich
orange, so as exactly to resemble the fine bee Euglossa
dimidiata, and both are found in the same parts of
South America. We have also in our own country spe-
cies of Bombylius which are almost exactly like bees.
In these cases the end gained by 'the mimicry is no
doubt freedom from attack, but it has sometimes an
altogether different purpose. There are a number of
parasitic flies whose larva? feed upon the larvas of bees,
such as the British genus Volucella and many of
the tropical Bombylii, and most of these are exactly
like the particular species of bee they prey upon, so
that they can enter their nests unsuspected to deposit
their eggs. There are also bees that mimic bees. The
cuckoo bees of the genus Nomada are parasitic on the
Andrenidse, and they resemble either wasps or species
of Andrena ; and the parasitic humble-bees of the genus
Apathus almost exactly resemble the species of humble-
bees in whose nests they are reared. Mr. Bates informs
us that he found numbers of these " cuckoo" bees and
flies on the Amazon, which all wore the livery of
working bees peculiar to the same country.

There is a genus of small spiders in the tropics which
feed on ants, and they are exactly like ants themselves,
which no doubt gives them more opportunity of seizing
their prey; and Mr. Bates found on the Amazon a
species of Mantis which exactly resembled the white
ants which it fed upon, as well as several species of
crickets (Scaphura), which resembled in a wonderful
manner different sand-wasps of large size, which are

RESEMBLANCES AMONG ANIMALS. 99

constantly on the search for crickets with which to
provision their nests.

Perhaps the most wonderful case of all is the large
caterpillar mentioned by Mr. Bates, which startled him
by its close resemblance to a small snake. The first
three segments behind the head were dilatable at the
will of the insect, and had on each side a large black
pupillated spot, which resembled the eye of the reptile.
Moreover, it resembled a poisonous viper, not a harm-
less species of snake, as was proved by the imitation of
keeled scales on the crown produced by the recumbent
feet, as the caterpillar threw itself backward !

The attitudes of many of the tropical spiders are
most extraordinary and deceptive, but little attention
has been paid to them. They often mimic other in-
sects, and some, Mr. Bates assures us, are exactly like
flower buds, and take their station in the axils of leaves,
where they remain motionless waiting for their prey.

Cases of Mimicry among the Vertebrata.

Having thus shown how varied and extraordinary
are the modes in which mimicry occurs among insects,
we have now to enquire if anything of the same kind
is to be observed among vertebrated animals. When
we consider all the conditions necessary to produce a
good deceptive imitation, we shall see at once that such
can very rarely occur in the higher animals, since they
possess none of those facilities for the almost infinite
modifications of external form which exist in the very
nature of insect organization. The outer covering of

H 2

100 MIMICRY, AND OTHER PROTECTIVE

insects being more or less solid and horny, they are
capable of almost any amount of change of form
and appearance without any essential modification
internally. In many groups the \vings give much of
the character, and these organs may be much modified
both in form and colour without interfering with their
special functions. Again, the number of species of
insects is so great, and there is such diversity of form
and proportion in every group, that the chances of an
accidental approximation in size, form, and colour, of
one insect to another of a different group, are very
considerable ; and it is these chance approximations
that furnish the basis of mimicry, to be continually
advanced and perfected by the survival of those
varieties only which tend in the right direction.

In the Vertebrata, on the contrary, the skeleton
being internal the external form depends almost en-
tirely on the proportions and arrangement of that
skeleton, which again is strictly adapted to the func-
tions necessary for the well-being of the animal. The
form cannot therefore be rapidly modified by variation,
and the thin and flexible integument will not admit
of the development of such strange protuberances as
occur continually in insects. The number of species of
each group in the same country is also comparatively
small, and thus the chances of that first accidental
resemblance which is necessary for natural selection
to work upon are much diminished. We can hardly
see the possibility of a mimicry by which the elk could
escape from the wolf, or the buffalo from the tiger.

RESEMBLANCES AMONG ANIMALS. 101

There is, however, in one group of Vertebrata such a
general similarity of form, that a very slight modi-
fication, if accompanied by identity of colour, would
produce the necessary amount of resemblance ; and
at the same time there exist a number of species which
it would be advantageous for others to resemble, since
they are armed with the most fatal weapons of offence.
We accordingly find that reptiles furnish us with a
very remarkable and instructive case of true mimicry.

Mimicry among Snakes.

There are in tropical America a number of venomous
snakes of the genus Elaps, which are ornamented with
brilliant colours disposed in a peculiar manner. The
ground colour is generally bright red, on which are
black bands of various widths and sometimes divided
into two or three by yellow rings. Now, in the same
country are found several genera of harmless snakes,
having no affinity whatever with the above, but
coloured exactly the same. For example, the poisonous
Elaps fulvius often occurs in Guatemala with simple
black bands on a coral-red ground ; and in the same
country is found the harmless snake Pliocerus equalis,
coloured and banded in identically the same manner.
A variety of Elaps corallinus has the black bands
narrowly bordered with yellow on the same red ground
colour, and a harmless snake, Homalocranium semi-
cinctum, has exactly the same markings, and both are
found in Mexico. The deadly Elaps lemniscatus has
the black bands very broad, and each of them divided

102 MIMICRY, AND OTHER PROTECTIVE

into three by narrow yellow rings ; and this again is
exactly copied by a harmless snake, Pliocerus elapoides,
which is found along with its model in Mexico.

&

But, more remarkable still, there is in South Ame-
rica a third group of snakes, the genus Oxyrhopus,
doubtfully venomous, and having no immediate affinity
with either of the preceding, which has also the same
curious distribution of colours, namely, variously dis-
posed rings of red, yellow, and black; and there are
some cases in which species of all three of these
groups similarly marked inhabit the same district.
For example, Elaps mipartitus has single black rings
very close together. It inhabits the west side of the
Andes, and in the same districts occur Pliocerus eury-
zonus and Oxyrhopus petolarius, which exactly copy
its pattern. In Brazil Elaps lemniscatus is copied by
Oxyrhopus trigeminus, both having black rings dis-
posed in threes. In Elaps hemiprichii the ground
colour appears to be black, with alternations of two
narrow yellow bands and a broader red one; and of
this pattern again we have an exact double in Oxy-
rhopus formosus, both being found in many localities
of tropical South America.

What adds much to the extraordinary character of
these resemblances is the fact, that nowhere in the
world but in America are there any snakes at all
which have this style of colouring.' Dr. Gunther, of
the British Museum, who has kindly furnished some
of the details here referred to, assures me that this is
the case ; and that red, black, and yellow rings occur

RESEMBLANCES AMONG ANIMALS. 103

together on no other snakes in the world but on Elaps
and the species which so closely resemble it. In all
these cases, the size and form as well as the coloura-
tion, are so much alike, that none but a naturalist
would distinguish the harmless from the poisonous
species.

Many of the small tree-frogs are no doubt also
mimickers. When seen in their natural attitudes, I
have been often unable to distinguish them from beetles
or other insects sitting upon leaves, but regret to say
I neglected to observe what species or groups they
most resembled, and the subject does not yet seem to
have attracted the attention of naturalists abroad.

Mimicry among Birds.

In the class of birds there are a number of cases
that make some approach to mimicry, such as the
resemblance of the cuckoos, a weak and defenceless
group of birds, to hawks and Gallinaccse. There is,
however, one example which goes much further than
this, and seems to be of exactly the same nature as
the many cases of insect mimicry which have been
already given. In Australia and the Moluccas there is
a genus of honeysuckers called Tropidorhynchus, good
sized birds, very strong and active, having powerful
grasping claws and long, curved, sharp beaks. They
assemble together in groups and small flocks, and they
have a very loud bawling note, which can be heard
at a great distance, and serves to collect a number
together in time of danger. They are very plentiful

104 MIMICRY, AND OTHER PROTECTIVE

and very pugnacious, frequently driving away crows,
and even hawks, which perch on a tree where a few of
them are assembled. They are all of rather dull and
obscure colours. Now in the same countries there is
a group of orioles, forming the genus Mimeta, much
weaker birds, which have lost the gay colouring of
their allies the golden orioles, being usually olive-green
or brown ; and in several cases these most curiously
resemble the Tropidorhynchus of the same island. For
example, in the island of Bouru is found the Tropido-
rhynchus bouruensis, of a dull earthy colour, and the
Mimeta bouruensis, which resembles it in the follow-
ing particulars : — The upper and under surfaces of the
two birds are exactly of the same tints of dark and
light brown ; the Tropidorhynchus has a large bare
black patch round the eyes; this is copied in the
Mimeta by a patch of black feathers. The top of the
head of the Tropidorhynchus has a scaly appearance
from the narrow scale-formed feathers, which are imi-
tated by the broader feathers of the Mimeta having a
dusky line down each. The Tropidorhynchus has a
pale ruff formed of curious recurved feathers on the
nape (which has given the whole genus the name of
Friar birds) ; this is represented in the Mimeta by a
pale band in the same position. Lastly, the bill of the
Tropidorhynchus is raised into a protuberant keel at the
base, and the Mimeta has the same character, although
it is not a common one in the genus. The result is,
that on a superficial examination the birds are identical,
although they have important structural differences,

RESEMBLANCES AMONG ANIMALS. 105

and cannot be placed near each other in any natural
arrangement. As a proof that the resemblance is really
deceptive, it may be mentioned that the Mimeta is
figured and described as a honeysucker in the costly
" Voyage de 1' Astrolabe," under the name of Philedon
bouruensis !

Passing to the island of Ceram, we find allied species
of both genera. The Tropidorhynchus subcornuttis is
of an earthy brown colour washed with yellow ochre,
with bare orbits, dusky cheeks, and the usual pale re-
curved nape-ruff. The Mimeta forsteni is absolutely
identical in the tints of every part of the body, the
details of which are imitated in the same manner as
in the Bouru birds already described. In two other
islands there is an approximation towards mimicry,
although it is not so perfect as in the two preced-
ing cases. In Timor the Tropidorhynchus timoriensis
is of the usual earthy brown above, with the nape-ruff
very prominent, the cheeks black, the throat nearly
white, and the whole under surface pale whitish brown.
These various tints are all well reproduced in Mimeta
virescens, the chief want of exact imitation being that
the throat and breast of the Tropidorhynchus has a
very scaly appearance, being covered with rigid pointed
feathers which are not imitated in the Mimeta, although
there are signs of faint dusky spots which may easily
furnish the groundwork of a more exact imitation by
the continued survival of favourable variations in the
same direction. There is also a large knob at the base
of the bill of the Tropidorhynchus which is not at all

106 MIMICRY, AND OTHER PEOTECT1VE

imitated by the Mimeta. In the island of Morty
(north of Gilolo) there exists the Tropidorhynchus
fuscicapillus, of a dark sooty brown colour, especially
on the head, while the under parts are rather lighter,
and the characteristic ruff of the nape is wanting.
Now it is curious that in the adjacent island of Gilolo
should be found the Mimeta phacochromus, the upper
surface of which is of exactly the same dark sooty
tint as the Tropidorhynchus, and is the only known
species that is of such a dark colour. The under side
is not quite light enough, but it is a good approxi-
mation. This Mimeta is a rare bird, and may very
probably exist in Morty, though not yet found there ;
or, on the other hand, recent changes in physical geo-
graphy may have led to the restriction of the Tropido-
rhynchus to that island, where it is very common.

Here, then, we have two cases of perfect mimicry
and two others of good approximation, occurring
between species of the same two genera of birds ; and
in three of these cases the pairs that resemble each
other are found together in the same island, and
to which they are peculiar. In all these cases the
Tropidorhynchus is rather larger than the Mimeta,
but the difference is not beyond the limits of varia-
tion in species, and the two genera are somewhat
alike in form and proportion. There are, no doubt,
some special enemies by which many small birds are
attacked, but which are afraid of the Tropidorhynchus
(probably some of the hawks), and thus it becomes
advantageous for the weak Mimeta to resemble the

RESEMBLANCES AMONG ANIMALS. 107

strong, pugnacious, noisy, and very abundant Tropi-
dorhynchus.

My friend, Mr. Osbert Salvin, has given me another
interesting case of bird mimicry. In the neighbour-
hood of Rio Janeiro is found an insect-eating hawk
(Harpagus diodon), and in the same district a bird-
eating hawk (Accipiter pileatus) which closely re-
sembles it. Both are of the same ashy tint beneath,
with the thighs and under wing-coverts reddish brown,
so that when on the wing and seen from below they
are undistinguishable. The curious point, however, is
that the Accipiter has a much wider range than the
Harpagus, and in the regions where the insect-eating
species is not found it no longer resembles it, the under
wing-coverts varjdng to white ; thus indicating that
the red-brown colour is kept true by its being useful
to the Accipiter to be mistaken for the insect-eating
species, which birds have learnt not to be afraid of.

Mimicry among Mammals.

Among the Mammalia the only case which may be
true mimicry is that of the insectivorous genus Cla-
dobates, found in the Malay countries, several species
of which very closely resemble squirrels. The size is
about the same, the long bushy tail is carried in the
same way, and the colours are very similar. In this
case the use of the resemblance must be to enable the
Cladobates to approach the insects or small birds on
which it feeds, under the disguise of the harmless fruit-
eating squirrel.

108 MIMICRY, AND OTHER PROTECTIVE

Objections to Mr. Bates' Theory of Mimicry.

Having now completed our survey of the most pro-
minent and remarkable cases of mimicry that have yet
been noticed, we must say something of the objections
that have been made to the theory of their production
given by Mr. Bates, and which we have endeavoured to
illustrate and enforce in the preceding pages. Three
counter explanations have been proposed. Professor
Westwood admits the fact of the mimicry and its pro-
bable use to the insect, but maintains that each species
was created a mimic for the purpose of the protection
thus afforded it. Mr. Andrew Murray, in his paper on
the " Disguises of Nature," inclines to the opinion that
similar conditions of food and of surrounding circum-
stances have acted in some unknown way to produce the
resemblances ; and when the subject was discussed before
the Entomological Society of London, a third objection
was added — that heredity or the reversion to ancestral
types of form and colouration, might have produced
many of the cases of mimicry.

Against the special creation of mimicking species
there are all the objections and difficulties in the way
of special creation in other cases, with the addition of
a few that are peculiar to it. The most obvious is,
that we have gradations of mimicry and of protective
resemblance — a fact which is strongly suggestive of a
natural process having been at work. Another very
serious objection is, that as mimicry has been shown
to be useful only to those species and groups which

RESEMBLANCES AMONG ANIMALS. 109

are rare and probably dying out, and would cease to
have any effect should the proportionate abundance of
the two species be reversed, it follows that on the
special-creation theory the one species must have been
created plentiful, the other rare ; and, notwithstanding
the many causes that continually tend to alter the pro-
portions of species, these two species must have always
been specially maintained at their respective propor-
tions, or the very purpose for which they each received
their peculiar characteristics would have completely
failed. A third difficulty is, that although it is very
easy to understand how mimicry may be brought
about by variation and the survival of the fittest, it
seems a very strange thing for a Creator to protect
an animal by making it imitate another, when the
very assumption of a Creator implies his power to
create it so as to require no such circuitous protection.
These appear to be fatal objections to the application
of the special-creation theory to this particular case.
The .other two supposed explanations, which may
be shortly expressed as the theories of " similar con-
ditions" and of " heredity," agree in making mimicry,
where it exists, an adventitious circumstance not ne-
cessarily connected with the well-being of the mimick-
ing species. But several of the most striking and
most constant facts which have been adduced, directly
contradict both these hypotheses. The law that mi-
micry is confined to a few groups only is one of these,
for " similar conditions " must act more or less on all
groups in a limited region, and " heredity " must

110 MIMICRY, AND OTHER PROTECTIVE

influence all groups related to each other in an equal
degree. Again, the general fact that those species
which mimic others are rare, while those which are
imitated are abundant, is in no way explained by either
of these theories, any more than is the frequent occur-
rence of some palpable mode of protection in the
imitated species. " Reversion to an ancestral type "
no way explains why the imitator and the imitated
always inhabit the very same district, whereas allied
forms of every degree of nearness and remoteness
generally inhabit different countries, and often dif-
ferent quarters of the globe; and neither it, nor
" similar conditions," will account for the likeness be-
tween species of distinct groups being superficial only —
a disguise, not a true resemblance ; for the imitation
of bark, of leaves, of sticks, of dung ; for the resem-
blance between species in different orders, and even
different classes and sub-kingdoms ; and finally, for the
graduated series of the phenomena, beginning with a
general harmony and adaptation of tint in autumn and
winter moths and in arctic and desert animals, and
ending with those complete cases of detailed mimicry
which not only deceive predacious animals, but puzzle
the most experienced insect collectors and the most
learned entomologists.

Mimicry by Female Insects only.

But there is yet another series of phenomena con-
nected with this subject, which considerably strengthens
the view here adopted, while it seems quite incompa-

RESEMBLANCES AMONG ANIMALS. Ill

tible with either of the other hypotheses ; namely, the
relation of protective colouring and mimicry to the
sexual differences of animals. It will be clear to every
one that if two animals, which as regards " external
conditions " and " hereditary descent," are exactly
alike, yet differ remarkably in colouration, one resem-
bling a protected species and the other not, the resem-
blance that exists in one only can hardly be imputed
to the influence of external conditions or as the effect
of heredity. And if, further, it can be proved that
the one requires protection more than the other, and
that in several cases it is that one which mimics the
protected species, while the one that least requires
protection never does so, it will afford very strong
corroborative evidence that there is a real connexion
between the necessity for protection and the pheno-
menon of mimicry. Now the sexes of insects offer
us a test of the nature here indicated, and appear to
furnish one of the most conclusive arguments in favour
of the theory that the phenomena termed " mimicry "
are produced by natural selection.

The comparative importance of the sexes varies
much in different classes of animals. In the higher
vertebrates, where the number of young produced at a
birth is small and the same individuals breed many
years in succession, the preservation of both sexes is
almost equally important. In all the numerous cases
in which the male protects the female and her offspring,
or helps to supply them with food, his importance in
the economy of nature is proportionately increased,

112 MIMICRY, AND OTHER PROTECTIVE

though it is never perhaps quite equal to that of the
female. In insects the case is very different ; they
pair but once in their lives, and the prolonged existence
of the male is in most cases quite unnecessary for the
continuance of the race. The female, however, must
continue to exist long enough to deposit her eggs in a
place adapted for the development and growth of the
progeny. Hence there is a wide difference in the need
for protection in the two sexes ; and we should, there-
fore, expect to find that in some cases the special pro-
tection given to the female was in the male less in
amount or altogether wanting. The facts entirely con-
firm this expectation. In the spectre insects (Phas-
midae) it is often the females alone that so strikingly
resemble leaves, wrhile the males show only a rude
approximation. The male Diadema misippus is a very
handsome and conspicuous butterfly, without a sign of
protective or imitative colouring, while the female is
entirely unlike her partner, and is one of the most
wonderful cases of mimicry on record, resembling
most accurately the common Danais chrysippus, in
whose company it is often found. So in several species
of South American Pieris, the males are white and
black, of a similar type of colouring to our own
" cabbage " butterflies, while the females are rich
yellow and buff, spotted and marked so as exactly to
resemble species of HeliconidaB with which they asso-
ciate in the forest. In the Malay archipelago is found
a Diadema which had always been considered a male
insect on account of its glossy metallic-blue tints,

RESEMBLANCES AMONG ANIMALS. 113

while its companion of sober brown was looked upon
as the female. I discovered, however, that the reverse
is the case, and that the rich and glossy colours of
the female are imitative and protective, since they
cause her exactly to resemble the common Euploea
midamus of the same regions, a species which has
been already mentioned in this essay as mimicked
by another butterfly, Papilio paradoxa. I have since
named this interesting species Diadema anomala (see
the Transactions of the Entomological Society, 1869,
p. 285). In this case, and in that of Diadema misippus,
there is no difference in the habits of the two sexes,
which fly in similar localities; so that the influence
of " external conditions " cannot be invoked here as
it has been in the case of the South American Pieris
pyrrha and allies, where the white males frequent
open sunny places, while the Heliconia-like females
haunt the shades of the forest.

We may impute to the same general cause (the
greater need of protection for the female, owing to
her weaker flight, greater exposure to attack, and
supreme importance) — the fact of the colours of female
insects being so very generally duller and less conspi-
cuous than those of the other sex. And that it is
chiefly due to this cause rather than to what Mr.
Darwin terms " sexual selection " appears to be
shown by the otherwise inexplicable fact, that in the
groups which have a protection of any kind inde-
pendent of concealment, sexual differences of colour
are either quite wanting or slightly developed. The

I

114 MIMICRY, AND OTHER PROTECTIVE

Heliconidse and Danaidse, protected by a disagree-
able flavour, have the females as bright and conspi-
cuous as the males, and very rarely differing at all
from them. The stinging Hymenoptera have the two
sexes equally well coloured. The Carabidaa, the Coc-
cinellidye, Chrysomelida3, and the Telephori have both
sexes equally conspicuous, and seldom differing in
colours. The brilliant Curculios, which are protected
by their hardness, are brilliant in both sexes. Lastly,
the glittering CetoniadaB and Buprestidas, which seem
to be protected by their hard and polished coats, their
rapid motions, and peculiar habits, present few sexual
differences of colour, while sexual selection has often
manifested itself by structural differences, such as-
horns, spines, or other processes.

Cause of the dull Colours of Female Birds.

The same law manifests itself in Birds. The female
while sitting on her eggs requires protection by con-
cealment to a much greater extent than the male ; and
we accordingly find that in a large majority of the
cases in which the male birds are distinguished by
unusual brilliancy of plumage, the females are much
more obscure, and often remarkably plain-coloured.
The exceptions are such as eminently to prove the
rule, for in most cases we can see a very good reason
for them. In particular, there are a few instances
among wading and gallinaceous birds in which the
female has decidedly more brilliant colours than the
male; but it is a most curious and interesting fact

RESEMBLANCES AMONG ANIMALS. 115

that in most if not all these cases the males sit upon
the eggs; so that this exception to the usual rule
almost demonstrates that it is because the process of
incubation is at once very important and very dan-
gerous, that the protection of obscure colouring is
developed. The most striking example is that of the
gray phalarope (Phalaropus fulicarius). When in
winter plumage, the sexes of this bird are alike in
colouration, but in summer the female is much the
most conspicuous, having a black head, dark wings,
and reddish-brown back, while the male is nearly
uniform brown, with dusky spots. Mr. Gould in his
" Birds of Great Britain " figures the two sexes in
both winter and summer plumage, and remarks on
the strange peculiarity of the usual colours of the two
sexes being reversed, and also on the still more curious
fact that the " male alone sits on the eggs," which
are deposited on the bare ground. In another British
bird, the dotterell, the female is also larger and more
brightly-coloured than the male ; and it seems to be
proved that the males assist in incubation even if they
do not perform it entirely, for Mr. Gould tells us,
"that they have been shot with the breast bare of
feathers, caused by sitting on the eggs." The small
quail-like birds forming the genus Turnix have also
generally large and bright-coloured females, and we
are told by Mr. Jerdon in his " Birds of India " that
"the natives report that during the breeding season
the females desert their eggs and associate in flocks
while the males are employed in hatching the eggs."

I 2

116 MIMICRY, AND OTHER PROTECTIVE

It is also an ascertained fact, that the females are
more bold and pugnacious than the males. A further
confimation of this view is to be found in the fact
(not hitherto noticed) that in a large majority of the
cases in which bright colours exist in both sexes incu-
bation takes place in a dark hole or in a dome-shaped
nest. Female kingfishers are often equally brilliant
with the male, and they build in holes in banks. Bee-
eaters, trogons, motmotSj and toucans, all build in
holes, and in none is there any difference in the sexes,
although they are, without exception, showy birds.
Parrots build in holes in trees, and in the majority
of cases they present no marked sexual difference
tending to concealment of the female. Woodpeckers
are in the same category, since though the sexes often
differ in colour, the female is not generally less con-
spicuous than the male. Wagtails and titmice build
concealed nests, and the females are nearly as gay as
their mates. The female of the pretty Australian bird
Pardalotus punctatus, is very conspicuously spotted
on the upper surface, and it builds in a hole in the
ground. The gay-coloured hang-nests (Icterinse) and
the equally brilliant tanagers may be well contrasted;
for the former, concealed in their covered nests, pre-
sent little or no sexual difference of colour — while the
open-nested tanagers have the females dull-coloured
and sometimes with almost protective tints. No doubt
there are many individual exceptions to the rule here
indicated, because many and various causes have com-
bined to determine both the colouration and the habits

RESEMBLANCES AMONG ANIMALS. 117

of birds. These have no doubt acted and re-acted
on each other; and when conditions have changed
one of these characters may often have become modi-
fied, while the other, though useless, may continue
by hereditary descent an apparent exception to what
otherwise seems a very general rule. The facts pre-
sented by the sexual differences of colour in birds and
their mode of nesting, are on the whole in perfect
harmony with that law of protective adaptation of
colour and form, which appears to have checked to
some extent the powerful action of sexual selection,
and to have materially influenced the colouring of
female birds, as it has undoubtedly done that of
female insects.

Use of the gaudy Colours of many Caterpillars.

Since this essay was first published a very curious
difficulty has been cleared up by the application of
the general principle of protective colouring. Great
numbers of caterpillars are so brilliantly marked and
coloured as to be very conspicuous even at a consi-
derable distance, and it has been noticed that such
caterpillars seldom hide themselves. Other species,
however, are green or brown, closely resembling the
colours of the substances on which they feed, while
others again imitate sticks, and stretch themselves out
motionless from a twig so as to look like one of its
branches. Now, as caterpillars form so large a part of
the food of birds, it was not easy to understand why
any of them should have such bright colours and mark

118 MIMICRY, AND OTHER PROTECTIVE

ings as to make them specially visible. Mr. Darwin
had put the case to me as a difficulty from another
point of view, for he had arrived at the conclusion that
brilliant colouration in the animal kingdom is mainly
clue to sexual selection, and this could not have acted
in the case of sexless larvse. Applying here the analogy
of other insects, I reasoned, that since some caterpillars
were evidently protected by their imitative colouring,
and others by their spiny or hairy bodies, the bright
colours of the rest must also be in some way useful to
them. I further thought that as some butterflies and
moths were greedily eaten by birds while others were
distasteful to them, and these latter were mostly of con-
spicuous colours, so probably these brilliantly coloured
caterpillars were distasteful, and therefore never eaten
by birds. Distastefulness alone would however be of
little service to caterpillars, because their soft and juicy
bodies are so delicate, that if seized and afterwards re-
jected by a bird they would almost certainly be killed.
Some constant and easily perceived signal was therefore
necessary to serve as a warning to birds never to touch
these uneatable kinds, and a very gaudy and conspi-
cuous colouring with the habit of fully exposing them-
selves to view becomes such a signal, being in strong
contrast with the green or brown tints and retiring
habits of the eatable kinds. The subject was brought
by me before the Entomological Society (see Proceed-
ings, March 4th, 1867), in order that those members
having opportunities for making observations might do
so in the following summer ; and I also wrote a letter to

RESEMBLANCES AMONG ANIMALS. 119

the Field newspaper, begging that some of its readers
would co-operate in making observations on what in-
sects were rejected by birds, at the same time fully
explaining the great interest and scientific importance
of the problem. It is a curious example of how few of
the country readers of that paper are at all interested
in questions of simple natural history, that I only
obtained one answer from a gentleman in Cumber-
land, who gave me some interesting observations on
the general dislike and abhorrence of all birds to the
"Gooseberry Caterpillar," probably that of the Magpie-
moth (Abraxas grossulariata). Neither young phea-
sants, partridges, nor wild-ducks could be induced to
eat it, sparrows and finches never touched it, and all
birds to whom he offered it rejected it with evident
dread and abhorrence. It will be seen that these ob-
servations are confirmed by those of two members of
the Entomological Society to whom we are indebted
for more detailed information.

In March, 1869, Mr. J. Jenner Weir communicated a
valuable series of observations made during many years,
but more especially in the two preceding summers, in
his aviary, containing the following birds of more or
less insectivorous habits: — Robin, Yellow - Hammer,
Reed-bunting, Bullfinch, Chaffinch, Crossbill, Thrush,
Tree-Pipit, Siskin, and Redpoll. He found that hairy
caterpillars were uniformly rejected ; five distinct species
were quite unnoticed by all his birds, and were allowed
to crawl about the aviary for days with impunity. The
spiny caterpillars of the Tortoiseshell and Peacock but-

120 MIMICRY, ASD OTHER PROTECTIVE

terflies were equally rejected ; but in both these cases
Mr. Weir thinks it is the taste, not the hairs or spines,
that are disagreeable, because some very young cater-
pillars of a hairy species were rejected although no hairs
were developed, and the smooth pupaa of the above-
named butterflies were refused as persistently as the
spined larvae. In these cases, then, both hairs and
spines would seem to be mere signs of uneatableness.

His next experiments were with those smooth gaily-
coloured caterpillars which never conceal themselves,
but on the contrary appear to court observation. Such
are those of the Magpie moth (Abraxas grossulariata),
whose caterpillar is conspicuously white and black
spotted — the Diloba coeruleocephala, whose larvae is
pale yellow with a broad blue or green lateral band —
the Cucullia verbasci, whose larvse is greenish white
with yellow bands and black spots, and Anthrocera
filipendulse (the six spot Burnet moth), whose cater-
pillar is yellow with black spots. These were given
to the birds at various times, sometimes mixed with
other kinds of larvse which were greedily eaten, but
they were in every case rejected apparently unnoticed,
and were left to crawl about till they died.

The next set of observations were on the dull-
coloured and protected larvse, and the results of nu-
merous experiments are thus summarised by Mr.
Weir. " All caterpillars whose habits are nocturnal,
which are dull coloured, with fleshy bodies and
smooth skins, are eaten with the greatest avidity.
Every species of green caterpillar is also much re-

RESEMBLANCES AMONG ANIMALS. 121

lished. All Geometry, whose larvse resemble twigs
as they stand out from the plant on their anal
prolegs, are invariably eaten."

At the same meeting Mr. A. G. Butler, of the
British Museum, communicated the results of his
observations with lizards, frogs, and spiders, which
strikingly corroborate those of Mr. Weir. Three green
lizards (Lacerta viridis) which he kept for several
years, were very voracious, eating all kinds of food,
from a lemon cheesecake to a spider, and devouring
flies, caterpillars, and humble bees ; yet there were
some caterpillars and moths which they would seize
only to drop immediately. Among these the principal
were the caterpillar of the Magpie moth (Abraxas
grossulariata) and the perfect six spot Burnet moth
(Anthrocera filipendulaB). These would be first seized
but invariably dropped in disgust, and afterwards left
unmolested. Subsequently frogs were kept and fed
with caterpillars from the garden, but two of these —
that of the before-mentioned Magpie moth, and that
of the V. moth (Halia wavaria), which is green with
conspicuous white or yellow stripes and black spots —
were constantly rejected. When these species were
first offered, the frogs sprang at them eagerly and
licked them into their mouths; no sooner, however,
had they done so than they seemed to be aware of
the mistake that they had made, and sat with gaping
mouths, rolling their tongues about until they had
got quit of the nauseous morsels.

With spiders the same thing occurred. These two

122 MIMICRY, AND OTHER PROTECTIVE

caterpillars were repeatedly put into the webs both of
the geometrical and hunting spiders (Epeira diadema
and Lycosa sp.), but in the former case they were
cut out and allowed to drop ; in the latter, after dis-
appearing in the jaws of their captor down his dark
silken funnel, they invariably reappeared, either from
below or else taking long strides up the funnel again.
Mr. Butler has observed lizards fight with and finally
devour humble bees, and a frog sitting on a bed of
stone-crop leap up and catch the bees which flew over
his head, and swallow them, in utter disregard of
their stings. It is evident, therefore, that the posses-
sion of a disagreeable taste or odour is a more effec-
tual protection to certain conspicuous caterpillars and
moths, than would be even the possession of a sting.
The observations of these two gentlemen supply
a very remarkable confirmation of the hypothetical
solution of the difficulty which I had given two years
before. And as it is generally acknowledged that
the best test of the truth and completeness of a
theory is the power which it gives us of prevision,
we may I think fairly claim this as a case in which
the power of prevision has been successfully exerted,
and therefore as furnishing a very powerful argu-
ment in favour of the truth of the theory of Natural
Selection.

t Summary.

I have now completed a brief, and necessarily very
imperfect, survey of the various ways in which the

RESEMBLANCES AMONG ANIMALS. 123

external form and colouring of animals is adapted to
be useful to them, either by concealing them from their
enemies or from the creatures they prey upon. It has,
I hope, been shown that the subject is one of much
interest, both as regard a true comprehension of the
place each animal fills in the economy of nature, and
the means by which it is enabled to maintain that
place; and also as teaching us how important a part
is played by the minutest details in the structure
of animals, and how complicated and delicate is the
equilibrium of the organic world.

My exposition of the subject having been necessarily
somewhat lengthy and full of details, it will be as
well to recapitulate its main points.

There is a general harmony in nature between the
colours of an animal and those of its habitation.
Arctic animals are white, desert animals are sand-
coloured ; dwellers among leaves and grass are green ;
nocturnal animals are dusky. These colours are not
universal, but are very general, and are seldom re-
versed. Going on a little further, we find birds,
reptiles, and insects, so tinted and mottled as exactly
to match the rock, or bark, or leaf, or flower, they
are accustomed to rest upon, — and thereby effec-
tually concealed. Another step in advance, and we
have insects which are formed as well as coloured so
as exactly to resemble particular leaves, or sticks, or
mossy twigs, or flowers; and in these cases very
peculiar habits and instincts come into play to aid
in the deception and render the concealment more

124 MIMICRY, AND OTHER PROTECTIVE

complete. We now enter upon a new phase of the
phenomena, and come to creatures whose colours neither
conceal them nor make them like vegetable or mineral
substances; on the contrary, they are conspicuous
enough, but they completely resemble some other
creature of a quite different group, while they differ
much in outward appearance from those with which
all essential parts of their organization show them
to be really closely allied. They appear like actors
or masqueraders dressed up and painted for amuse-
ment, or like swindlers endeavouring to pass them-
selves off for well-known and respectable members
of society. What is the meaning of this strange
travestie ? Does Nature descend to imposture or mas-
querade ? We answer, she does not. Her principles
are too severe. There is a use in every detail of
her handiwork. The resemblance of one animal to
another is of exactly the same essential nature as the
resemblance to a leaf, or to bark, or to desert sand,
and answers exactly the same purpose. In the one
case the enemy will not attack the leaf or the bark,
and so the disguise is a safeguard ; in the other case
it is found that for various reasons the creature re-
sembled is passed over, and not attacked by the usual
enemies of its order, and thus the creature that
resembles it has an equally effectual safeguard. We
are plainly shown that the disguise is of the same
nature in the two cases, by the occurrence in the
same group of one species resembling a vegetable
substance, while another resembles a living animal of

RESEMBLANCES AMONG ANIMALS. 125

another group; and we know that the creatures re-
sembled, possess an immunity from attack, by their
being always very abundant, by their being conspi-
cuous and not concealing themselves, and by their
having generally no visible means of escape from
their enemies ; while, at the same time, the particular
quality that makes them disliked is often very clear,
such as a nasty taste or an indigestible hardness.
Further examination reveals the fact that, in several
cases of both kinds of disguise, it is the female only
that is thus disguised ; and as it can be shown that the
female needs protection much more than the male,
and that her preservation for a much longer period is
absolutely necessary for the continuance of the race,
we have an additional indication that the resemblance
is in all cases subservient to a great purpose — the
preservation of the species.

In endeavouring to explain these phenomena as
having been brought about by variation and natural
selection, we start with the fact that white varieties
frequently occur, and when protected from enemies
show no incapacity for continued existence and in-
crease. We know, further, that varieties of many
other tints occasionally occur; and as f'the survival
of the fittest " must inevitably weed out those whose
colours are prejudicial and preserve those whose
colours are a safeguard, we require no other mode of
accounting for the protective tints of arctic and
desert animals. But this being granted, there is
such a perfectly continuous and graduated series of

126 MIMICRY, AND OTHER PROTECTIVE

examples of every kind of protective imitation, up to
the most wonderful cases of what is termed "mimicry,"
that we can find no place at which to draw the line,
and say, — so far variation and natural selection will
account for the phenomena, but for all the rest we
require a more potent cause. The counter theories
that have been proposed, that of the " special creation "
of each imitative form, that of the action of " similar
conditions of existence " for some of the cases, and of
the laws of Ce hereditary descent and the reversion to
ancestral forms " for others, — have all been shown
to be beset with difficulties, and the two latter to be
directly contradicted by some of the most constant and
most remarkable of the facts to be accounted for.

General deductions as to Colour in Mature.

The important part that " protective resemblance "
has played in determining the colours and markings
of many groups of animals, will enable us to under-
stand the meaning of one of the most striking facts
in nature, the uniformity in the colours of the vege-
table as compared with the wonderful diversity of the
animal world. There appears no good reason why
trees and shrubs should not have been adorned with
as many varied hues and as strikingly designed pat-
terns as birds and butterflies, since the gay colours
of flowers show that there is no incapacity in vege-
table tissues to exhibit them. But even flowers them-
selves present us with none of those wonderful designs,
those complicated arrangements of stripes and dots

RESEMBLANCES AMONG ANIMALS. 127

and patches of colour, that harmonious blending of
hues in lines and bands and shaded spots, which are
so general a feature in insects. It is the opinion of
Mr. Darwin that we owe much of the beauty of
flowers to the necessity of attracting insects to aid
in their fertilisation, and that much of the develop-
ment of colour in the animal world is due to " sexual
selection,'* colour being universally attractive, and thus
leading to its propagation and increase; but while
fully admitting this, it will be evident from the facts
and arguments here brought forward, that very much
of the variety both of colour and markings among
animals is due to the supreme importance of con-
cealment, and thus the various tints "of minerals and
vegetables have been directly reproduced in the ani-
mal kingdom, and again and again modified as more
special protection became necessary. We shall thus
have two causes for the development of colour in the
animal world, and shall be better enabled to under-
stand how, by their combined and separate action,
the immense variety we now behold has been pro-
duced. Both causes, however, will come under the
general law of " Utility," the advocacy of which, in its
broadest sense, we owe almost entirely to Mr. Darwin.
A more accurate knowledge of the varied phenomena
connected with this subject may not improbably give
us some information both as to the senses and the
mental faculties of the lower animals. For it is
evident that if colours which please us also attract
them, and if the various disguises which have been

128 MIMICRY, AND OTHER PROTECTIVE

here enumerated are equally deceptive to them as to
ourselves, then both their powers of vision and their
faculties of perception and emotion, must be essentially
of the same nature as our own — a fact of high philo-
sophical importance in the study of our own nature
and our true relations to the lower animals.

Conclusion.

Although such a variety of interesting facts have
been already accumulated, the subject we have been
discussing is one of which comparatively little is really
known. The natural history of the tropics has never
yet been studied on the spot with a full appreciation
of " what to observe " in this matter. The varied
ways in which the colouring and form of animals serve
for their protection, their strange disguises as vege-
table or mineral substances, their wonderful mimicry
of other beings, offer an almost unworked and inex-
haustible field of discovery for the zoologist, and will
assuredly throw much light on the laws and conditions
which have resulted in the wonderful variety of colour,
shade, and marking which constitutes one of the most
pleasing characteristics of the animal world, but the
immediate causes of which it has hitherto been most
difficult to explain.

If I have succeeded in showing that in this wide
and picturesque domain of nature, results which have
hitherto been supposed to depend either upon those
incalculable combinations of laws which we term
chance or upon the direct volition of the Creator, are

RESEMBLANCES AMONG ANIMALS. 129

really due to the action of comparatively well-known
and simple causes, I shall have attained my present
purpose, which has been to extend the interest so
generally felt in the more striking facts of natural
history to a large class of curious but much neglected
details ; and to further, in however slight a degree,
our knowledge of the subjection of the phenomena of
life to the "Reign of Law."

130

IV.

THE MALAYAN PAPILIONID^ OR SWAL-
LOW-TAILED BUTTERFLIES, AS ILLUS-
TRATIVE OF THE THEORY OF NATURAL
SELECTION.

Special Value of the Diurnal Lepidoptera for enquiries
of this nature.

WHEN the naturalist studies the habits, the structure,
or the affinities of animals, it matters little to which
group he especially devotes himself; all alike offer him
endless materials for observation and research. But,
for the purpose of investigating the phenomena of geo-
graphical distribution and of local, sexual, or general
variation, the several groups differ greatly in their
value and importance. Some have too limited a range,
others are not sufficiently varied in specific forms,
while, what is of most importance, many groups
have not received that amount of attention over the
whole region they inhabit, which could furnish mate-
rials sufficiently approaching to completeness to enable
us to arrive at any accurate conclusions as to the
phenomena they present as a whole. It is in those
groups which are, and have long been, favourites with
collectors, that the student of distribution and varia-
tion will find his materials the most satisfactory, from
their comparative completeness.

THE MALAYAN PAPILIOXIDM, ETC. 131

Pre-eminent among such groups are the diurnal
Lepidoptera or Butterflies, whose extreme beauty
and endless diversity have led to their having been
assiduously collected in all parts of the world, and
to the numerous species and varieties having been
figured in a series of magnificent works, from those
of Cramer, the contemporary of Linnseus, down to
the inimitable productions of our own Hewitson.*
But, besides their abundance, their universal distri-
bution, and the great attention that has been paid
to them, these insects have other qualities that espe-
cially adapt them to elucidate the branches of inquiry
already alluded to. These are, the immense develop-
ment and peculiar structure of the wings, which not
only vary in form more than those of any other
insects, but offer on both surfaces an endless variety
of pattern, colouring, and texture. The scales, with
which they are more or less completely covered, imi-
tate the rich hues and delicate surfaces of satin or
of velvet, glitter with metallic lustre, or glow with
the changeable tints of the opal. This delicately
painted surface acts as a register of the minutest
differences of organization — a shade of colour, an
additional streak or spot, a slight modification of
outline continually recurring with the greatest regu-
larity and fixity, while the body and all its other

* W. C. Hewitson, Esq., of Oatlands, Walton-on-Thames,
author of " Exotic Butterflies " and several other works, illus-
trated by exquisite coloured figures drawn by himself; and
owner of the finest collection of Butterflies in the world.

K 2

132 THE MALAYAN PAPILIONID1E AS

members exhibit no appreciable change. The wings
of Butterflies, as Mr. Bates has well put it, "serve
as a tablet on which Nature writes the story of the
modifications of species ; " they enable us to perceive
changes that would otherwise be uncertain and diffi-
cult of observation, and exhibit to us on an enlarged
scale the effects of the climatal and other physical
conditions which influence more or less profoundly
the organization of every living thing.

A proof that this greater sensibility to modifying
causes is not imaginary may, I think, be drawn from
the consideration, that while the Lepidoptera as a
whole are of all insects the least essentially varied in
form, structure, or habits, yet in the number of their
specific forms they are not much inferior to those
orders which range over a much wider field of nature,
and exhibit more deeply seated structural modifica-
tions. The Lepidoptera are all vegetable-feeders in
their larva-state, and suckers of juices or other liquids
in their perfect form. In their most widely separated
groups they differ but little from a common type,
and offer comparatively unimportant modifications of
structure or of habits. The Coleoptera, the Diptera,
or the Hymenoptera, on the other hand, present far
greater and more essential variations. In either of
these orders we have both vegetable and animal-
feeders, aquatic, and terrestrial, and parasitic groups.
Whole families are devoted to special departments in
the economy of nature. Seeds, fruits, bones, car-
cases, excrement, bark, have each their special and

ILLUSTRATIVE OF NATURAL SELECTION. 133

dependent insect tribes from among them; whereas
the Lepidoptera are, with but few exceptions, confined
to the one function of devouring the foliage of living
vegetation. We might therefore anticipate that their
species - population would be only equal to that of
sections of the other orders having a similar uniform
mode of existence ; and the fact that their numbers
are at all comparable with those of entire orders, so
much more varied in organization and habits, is, I
think, a proof that they are in general highly sus-
ceptible of specific modification.

Question of the rank of the Papilionidce.

The Papilionidas are a family of diurnal Lepidop-
tera which have hitherto, by almost universal consent,
held the first rank in the order ; and though this
position has recently been denied them, I cannot
altogether acquiesce in the reasoning by which it has
been proposed to degrade them to a lower rank. In
Mr. Bates's most excellent paper on the Heliconida3,
(published in the Transactions of the Linnasan So-
ciety, vol. xxiii., p. 495) he claims for that family
the highest position, chiefly because of the imperfect
structure of the fore legs, which is there carried to
an extreme degree of abortion, and thus removes
them further than any other family from the Hes-
peridge and Heterocera, which all have perfect legs.
Now it is a question whether any amount of differ-
ence which is exhibited merely in the imperfection
or abortion of certain organs, can establish in the

13 1 THE MALAYAN PAPILIONIVM AS

group exhibiting it a claim to a higli grade of organ-
ization ; still less can this be allowed when another
group along with perfection of structure in the same
organs, exhibits modifications peculiar to it, together
with the possession of an organ which in the re-
mainder of the order is altogether wanting. This is,
however, the position of the Papilionidae. The per-
fect insects possess two characters quite peculiar to
them. Mr. Edward Doubleday, in his " Genera of
Diurnal Lepidoptera," says, " The Papilionidae may
be known by the apparently four-branched median
nervule and the spur on the anterior tibiae, charac-
ters found in no other family." The four -branched
median nervule is a character so constant, so pecu-
liar, and so well marked, as to enable a person to
tell, at a glance at the wings only of a butterfly,
whether it does or does not belong to this family ;
and I am not aware that any other group of butter-
flies, at all comparable to this in extent and modifi-
cations of form, possesses a character in its neuration
to which the same degree of certainty can be attached.
The spur on the anterior tibiae is also found in some
of the Hesperidae, and is therefore supposed to show a
direct affinity between the two groups : but I do not
imagine it can counterbalance the differences in neura-
tion and in every other part of their organization.
The most characteristic feature of the Papilionidae,
however, and that on which I think insufficient
stress has been laid, is undoubtedly the peculiar
structure of the larvae. These all possess an extra-

ILLUSTRATIVE OF NATURAL SELECTION. 135

ordinary organ situated on the neck, the well-known
Y-shaped tentacle, which is entirely concealed in a
state of repose, but which is capable of being sud-
denly thrown out by the insect when alarmed. When
we consider this singular apparatus, which in some
species is nearly half an inch long, the arrange-
ment of muscles for its protrusion and retraction,
its perfect concealment during repose, its blood-red
colour, and the suddenness with which it can be
thrown out, we must, I think, be led to the con-
clusion that it serves as a protection to the larva,
by startling and frightening away some enemy when
about to seize it, and is thus one of the causes which
has led to the wide extension and maintained the per-
manence of this now dominant group. Those who
believe that such peculiar structures can only have
arisen by very minute successive variations, each one
advantageous to its possessor, must see, in the pos-
session of such an organ by one group, and its
complete absence in every other, a proof of a very
ancient origin and of very long-continued modifica-
tion. And such a positive structural addition to
the organization of the family, subserving an impor-
tant function, seems to me alone sufficient to warrant
us in considering the Papilionidse as the most highly
developed portion of the whole order, and thus in
retaining it in the position which the size, strength,
beauty, and general structure of the perfect insects
liave been generally thought to deserve.

In Mr. Trimen's paper on "Mimetic Analogies

136 THE MALAYAN PAPJLIONJD^E AS

among African Butterflies," in the Transactions of the
Linnsean Society, for 1868, lie has argued strongly
in favour of Mr. Bates' views as to the higher posi-
tion of the Danaidse and the lower grade of the
Papilionidse, and has adduced, among other facts, the
undoubted resemblance of the pupa of Parnassius, a
genus of Papilionidoa, to that of some HesperidsB and
moths. I admit, therefore, that he has proved the
Papilionidas to have retained several characters of
the nocturnal Lepidoptera which the Danaidse have
lost, but I deny that they are therefore to be con-
sidered lower in the scale of organization. Other
characters may be pointed out which indicate that
they are farther removed from the moths even than
the Danaidse. The club of the antennae is the most
prominent and most constant feature by which but-
terflies may be distinguished from moths, and of
all butterflies the Papilionidaa have the most beauti-
ful and most perfectly developed clubbed antennae.
Again, butterflies and moths are broadly character-
ised by their diurnal and nocturnal habits respectively,
and the Papilionidse, with their close allies the Pier-
idge, are the most pre-eminently diurnal of butterflies,
most of them lovers of sunshine, and not presenting
a single crepuscular species. The great group of the
Nymphalidse, on the other hand (in which Mr. Bates
includes the Danaidse and Heliconidae as sub-fami-
lies), contains an entire sub-family (Brassolidse) and
a number of genera, such as Thaumantis, Zeuxidia,
Pavonia, &c., of crepuscular habits, while a large

ILLUSTRATIVE OF NATURAL SELECTION. 137

proportion of the Satyridae and many of the Dana-
idse are shade -loving butterflies. This question, of
what is to be considered the highest type of any
group of organisms, is one of such general interest to
naturalists that it will be well to consider it a little
further, by a comparison of the Lepidoptera with some
groups of the higher animals.

Mr. Trimen's argument, that the lepidopterous type,
like that of birds, being pre-eminently aerial, " there-
fore a diminution of the ambulatory organs, instead
of being a sign of inferiority, may very possibly in-
dicate a higher, because a more thoroughly aerial
form," is certainly unsound, for it would imply that
the most aerial of birds (the swift and the frigate-
birds, for example) are the highest in the scale of
bird-organization, and the more so on account of their
feet being very ill adapted for walking. But no or-
nithologist has ever so classed them, and the claim to
the highest rank among birds is only disputed be-
tween three groups, all very far removed from these.
They are — 1st. The Falcons, on account of their
general perfection, their rapid flight, their piercing
vision, their perfect feet armed with retractile claws,
the beauty of their forms, and the ease and rapidity of
their motions ; 2nd. The Parrots, whose feet, though
ill-fitted for walking, are perfect as prehensile organs,
and which possess large brains with great intelligence,
though but moderate powers of flight ; and, 3rd. The
Thrushes or Crows, as typical of the perching birds,
on account of the well-balanced development of their

138 THE MALAYAN PAPILIONID& AS

whole structure, in which no organ or function has
attained an undue prominence.

Turning now to the Mammalia, it might be argued
that as they are pre-eminently the terrestrial type
of vertebrates, to walk and run well is essential to the
typical perfection of the group ; but this would give
the superiority to the horse, the deer, or the hunting
leopard, instead of to the Quadrumana. We seem here
to have quite a case in point, for one group of Quad-
rumana, the Lemurs, is undoubtedly nearer to the
low Insectivora and Marsupials than the Carnivora or
the Ungulata, as shown among other characters by
the Opossums possessing a hand with perfect opposable
thumb, closely resembling that of some of the Lemurs ;
and by the curious Graleopithecus, which is sometimes
classed as a Lemur, and sometimes with the Insecti-
vora. Again, the implacental mammals, including
the Ornithodelphia and the Marsupials, are admitted
to be lower than the placental series. But one of the
distinguishing characters of the Marsupials is that the
young are born blind and exceedingly imperfect, and
it might therefore be argued that those orders in
which the young are born most perfect are the highest,
because farthest from the low Marsupial type. This
would make the Ruminants and Ungulata higher than
the Quadrumana or the Carnivora. But the Mam-
malia offer a still more remarkable illustration of the
fallacy of this mode of reasoning, for if there is one
character more than another which is essential and
distinctive of the class, it is that from which it derives

ILLUSTRATIVE OF NATURAL SELECTION. 139

its name, the possession of mammary glands and the
power of suckling the young. What more reasonable,
apparently, than to argue that the group in which
this important function is most developed, that in
which the young are most dependent upon it, and
for the longest period, must be the highest in the
Mammalian scale of organization? Yet this group is
the Marsupial, in which the young commence suckling
in a foetal condition, and continue to do so till they
are fully developed, and are therefore for a long time
absolutely dependent on this mode of nourishment.

These examples, I think, demonstrate that we can-
not settle the rank of a group by a consideration of
the degree in which certain characters resemble or
differ from those in what is admitted to be a lower
group ; and they also show that the highest group of
a class may be more closely connected to one of the
lowest, than some other groups which have developed
laterally and diverged farther from the parent type,
but which yet, owing to want of balance or too great
specialization in their structure, have never reached
a high grade of organization. The Quadrumana afford
a very valuable illustration, because, owing to their
undoubted affinity with man, we feel certain that they
are really higher than any other order of Mammalia,
while at the same time they are more distinctly allied
to the lowest groups than many others. The case of
the PapilionidaB seems to me so exactly parallel to
this, that, while I admit all the proofs of affinity
with the undoubtedly lower groups of Hesperidse and

140 THE MALAYAN PAPILIONIDJE AS

moths, I yet maintain that, owing to the complete
and even development of every part of their organi-
zation, these insects best represent the highest per-
fection to which the butterfly type has attained, and
deserve to be placed at its head in every system of
classification.

Distribution of tlie Papilionidce.

The Papilionidaa are pretty widely distributed over
the earth, but are especially abundant in the tropics,
where they attain their maximum of size and beauty,
and fhe greatest variety of form and colouring.
South America, North India, and the Malay Islands
are the regions where these fine insects occur in the
greatest profusion, and where they actually become
a not unimportant feature in the scenery. In the
Malay Islands in particular, the giant Ornithoptera?
may be frequently seen about the borders of the cul-
tivated and forest districts, their large size, stately
flight, and gorgeous colouring rendering them even
more conspicuous than the generality of birds. In
the shady suburbs of the town of Malacca two large
and handsome Papilios (Memnon and ISTephelus) are
not uncommon, flapping with irregular flight along
the roadways, or, in the early morning, expanding
their wings to the invigorating rays of the sun. In
Amboyna and other towns of the Moluccas, the mag-
nificent Deiphobus and Severus, and occasionally even
the azure-winged Ulysses, frequent similar situations,
fluttering about the orange-trees and flower-beds, or

ILLUSTRATIVE OF NATURAL SELECTION. 141

sometimes even straying into the narrow bazaars or
covered markets of the city. In Java the golden-
dusted Arjuna may often be seen at damp places on
the roadside in the mountain districts, in company
with Sarpedon, Bathycles, and Agamemnon, and less
frequently the beautiful swallow-tailed Antiphates.
In the more luxuriant parts of these islands one can
hardly take a morning's walk in the neighbourhood
of a town or village without seeing three or four
species of Papilio, and often twice that number. No
less than 130 species of the family are now known
to inhabit the Archipelago, and of these ninety-six
were collected by myself. Thirty species are found
in Borneo, being the largest number in any one island,
twenty-three species having been obtained by myself
in the vicinity of Sarawak; Java has twenty-eight
species ; Celebes twenty-four, and the Peninsula of
Malacca, twenty- six species. Further east the num-
bers decrease ; Batchian producing seventeen, and New
Guinea only fifteen, though this number is certainly
too small, owing to our present imperfect knowledge
of that great island.

Definition of the word Species.

In estimating these numbers I have had the usual
difficulty to encounter, of determining what to con-
sider species and what varieties. The Malayan region,
consisting of a large number of islands of generally
great antiquity, possesses, compared to its actual area,
a great number of distinct forms, often indeed dis-

142 THE MALAYAN PAP1LIONID& AS

tinguished by very slight characters, but in most
cases so constant in large series of specimens, and
so easily separable from each other, that I know not
on what principle we can refuse to give them the
name and rank of species. One of the best and most
orthodox definitions is that of Pritchard, the great
ethnologist, who says, that " separate origin and dis-
tinctness of race, evinced by a constant transmission of
some characteristic peculiarity of organization," consti-
tutes a species. Now leaving out the question of
" origin," which we cannot determine, and taking
only the proof of separate origin, " the constant trans-
mission of some characteristic peculiarity of organiza-
tion" we have a definition which will compel us to
neglect altogether the amount of difference between
any two forms, and to consider only whether the dif-
ferences that present themselves are permanent. The
rule, therefore, I have endeavoured to adopt is, that
when the difference between two forms inhabiting
separate areas seems quite constant, when it can be
defined in words, and when it is not confined to a
single peculiarity only, I have considered such forms
to be species. When, however, the individuals of
each locality vary among themselves, so as to cause
the distinctions between the two forms to become
inconsiderable and indefinite, or where the differences,
though constant, are confined to one particular only,
such as size, tint, or a single point of difference in
marking or in outline, I class one of the forms as a
variety of the other.

ILLUSTRATIVE OF NATURAL SELECTION. 143

I find as a general rule that the constancy of species
is in an inverse ratio to their range. Those which
are confined to one or two islands are generally very
constant. When they extend to many islands, con-
siderable variability appears ; and when they have an
extensive range over a large part of the Archipelago,
the amount of unstable variation is very large. These
facts are explicable on Mr. Darwin's principles. When
a species exists over a wide area, it must have had,
and probably still possesses, great powers of disper-
sion. Under the different conditions of existence in
various portions of its area, different variations from
the type would be selected, and, were they completely
isolated, would soon become distinctly modified forms ;
but this process is checked by the dispersive powers
of the whole species, which leads to the more or less
frequent intermixture of the incipient varieties, which
thus become irregular and unstable. Where, how-
ever, a species has a limited range, it indicates less
active powers of dispersion, and the process of modi-
fication under changed conditions is less interfered
with. The species will therefore exist under one or
more permanent forms according as portions of it have
been isolated at a more or less remote period.

Laws and Modes of Variation.

What is commonly called variation consists of several
distinct phenomena which have been too often con-
founded. I shall proceed to consider these under the
heads of — 1st, simple variability ; 2nd, polymorphism ;

144 THE MALAYAN PAPILIONID& AS

3rd, local forms ; 4th, co-existing varieties ; 5th, races
or subspecies ; and 6th, true species.

1. Simple variability. — Under this head I include all
those cases in which the specific form is to some extent
unstable. Throughout the whole range of the species,
and even in the progeny of individuals, there occur
continual and uncertain differences of form, analogous
to that variability which is so characteristic of domestic
breeds. It is impossible usefully to define any of these
forms, because there are indefinite gradations to each
other form. Species which possess these characteristics
have always a wide range, and are more frequently the
inhabitants of continents than of islands, though such
cases are always exceptional, it being far more common
for specific forms to be fixed within very narrow limits
of variation. The only good example of this kind of
variability which occurs among the Malayan Papilio-
nida3 is in Papilio Severus, a species inhabiting all the
islands of the Moluccas and New Guinea, and exhibit-
ing in each of them a greater amount of individual
difference than often serves to distinguish well -
marked species. Almost equally remarkable are the
variations exhibited in most of the species of Ornithop-
tera, which I have found in some cases to extend even
to the form of the wing and the arrangement of the
nervures. Closely allied, however, to these variable
species are others which, though differing slightly from
them, are constant and confined to limited areas. After
satisfying oneself, by the examination of numerous
specimens captured in their native countries, that the

ILLUSTRATIVE OF NATURAL SELECTION. 145

one set of individuals are variable and the others are
not, it becomes evident that by classing all alike as
varieties of one species we shall be obscuring an impor-
tant fact in nature ; and that the only \> ay to exhibit
that fact in its true light is to treat the invariable local
form as a distinct species, even though it does not offer
better distinguishing characters than do the extreme
forms of the variable species. Cases of this kind are
the Ornithoptera Priamus, which is confined to the
islands of Ceram and Amboyna, and is very constant
in both sexes, while the allied species inhabiting New
Guinea and the Papuan Islands is exceedingly variable ;
and in the island of Celebes is a species closely allied to
the variable P. Severus, but which, being exceedingly
constant, I have described as a distinct species under
the name of Papilio Pertinax.

2. Polymorphism or dimorphism. — By this term I
understand the co-existence in the same locality of two
or more distinct forms, not connected by intermediate
gradations, and all of which are occasionally produced
from common parents. These distinct forms generally
occur in the female sex only, and their offspring, in-
stead of being hybrids, or like the two parents, appear
to reproduce all the distinct forms in varying propor-
tions. I believe it will be found that a considerable
number of what have been classed as varieties are really
cases of polymorphism. Albinoism and melanism are
of this character, as well as most of those cases in
which well-marked varieties occur in company with the
parent species, but without any intermediate forms. If

L

146 THE MALAYAN PAPILIONIDJE AS

these distinct forms breed independently, and are never
reproduced from a common parent, they must be con-
sidered as separate species, contact without intermix-
ture being a good test of specific difference. On the
other hand, intercrossing without producing an inter-
mediate race is a test of dimorphism. I consider,
therefore, that under any circumstances the term
" variety " is wrongly applied to such cases.

The Malayan Papilionidas exhibit some very curious
instances of polymorphism, some of which have been
recorded as varieties, others as distinct species; and
they all occur in the female sex. Papilio Memnon
is one of the most striking, as it exhibits the mixture
of simple variability, local and polymorphic forms, all
hitherto classed under the common title of varieties.
The polymorphism is strikingly exhibited by the fe-
males, one set of which resemble the males in form,
with a variable paler colouring ; the others have a
large spatulate tail to the hinder wings and a distinct
style of colouring, which causes them closely to resem-
ble P. Coon, a species having the two sexes alike and
inhabiting the same countries, but with which they have
no direct affinity. The tailless females exhibit simple
variability, scarcely two being found exactly alike even
in the same locality. The males of the island of Borneo
exhibit constant differences of the under surface, and
may therefore be distinguished as a local form, while
the continental specimens, as a whole, offer such large
and constant differences from those of the islands, that
I am inclined to separate them as a distinct species, to*

ILLUSTRATIVE OF NATURAL SELECTION. 147

which the name P. Androgeus (Cramer) may be ap-
plied. We have here, therefore, distinct species, local
forms, polymorphism, and simple variability, which
seem to me to be distinct phenomena, but which have
been hitherto all classed together as varieties. I may
mention that the fact of these distinct forms being one
species is doubly proved. The males, the tailed and
tailless females, have all been bred from a single group
of the larvae, by Messrs. Payen and Bocarme, in Java,
and I myself captured, in Sumatra, a male P. Memnon,
and a tailed female P. Achates, under circumstances
which led me to class them as the same species.

Papilio Pammon offers a somewhat similar case.
The female was described by Linnaeus as P. Polytes,
and was considered to be a distinct species till Wes-
termann bred the two from the same larvae (see
Boisduval, " Species General des Lepidopteres," p. 272).
They were therefore classed as sexes of one species by
Mr. Edward Doubleday, in his " Genera of Diurnal
Lepidoptera," in 1846. Later, female specimens were
received from India closely resembling the male in-
sect, and this was held to overthrow the authority of
M. Westermann's observation, and to re-establish P.
Polytes as a distinct species ; and as such it accord-
ingly appears in the British Museum List of Papilio-
nidae in 1856, and in the Catalogue of the East India
Museum in 1857. This discrepancy is explained by the
fact of P. Pammon having two females, one closely re-
sembling the male, while the other is totally different
from it. A long familiarity with this insect (which

L 2

148 THE MALAYAN PAPILIONID^ AS

replaced by local forms or by closely allied species, occurs
in every island of the Archipelago) has convinced me
of the correctness of this statement ; for in every place
where a male allied to P. Pammon is found, a female
resembling P. Polytes also occurs, and sometimes,
though less frequently than on the continent, another
female closely resembling the male : while not only has
no male specimen of P. Polytes yet been discovered,
but the female (Polytes) has never yet been found in
localities to which the male (Pammon) does not extend.
In this case, as in the last, distinct species, local forms,
and dimorphic specimens, have been .confounded under
the common appellation of varieties.

But, besides the true P. Polytes, there are several
allied forms of females to be considered, namely, P.
Theseus (Cramer), P. Melanides (De Haan), P. Elyros
(G. R. Gray), and P. Romulus (Linnaeus). The dark
female figured by Cramer as P. Theseus seems to be
the common and perhaps the only form in Sumatra,
whereas in Java, Borneo, and Timor, along with males
quite identical with those of Sumatra, occur females
of the Polytes form, although a single specimen of
the true P. Theseus taken at Lombock would seem to
show that the two forms do occur together. In the
allied species found in the Philippine Islands (P. Al-
phenor, Cramer = P. Ledebouria, Eschscholtz, the
female of which is P. Elyros, G. R. Gray,) forms
corresponding to these extremes occur, along with a
number of intermediate varieties, as shown by a fine
series in the British Museum. We have here an

ILLUSTRATIVE OF NATURAL SELECTION. 149

indication of how dimorphism may be produced ; for
let the extreme Philippine forms be better suited to
their conditions of existence than the intermediate
connecting links, and the latter will gradually die
out, leaving two distinct forms of the same insect,
each adapted to some special conditions. As these
conditions are sure to vary in different districts, it
will often happen, as in Sumatra and Java, that the
one form will predominate in the one island, the
other in the adjacent one. In the island of Borneo
there seems to be a third form; for P. Melanides
(De Haan) evidently belongs to this group, and has
all the chief characteristics of P. Theseus, with a
modified colouration of the hind wings. I now come
to an insect which, if I am correct, offers one of the
most interesting cases of variation yet adduced. Pa-
pilio Romulus, a butterfly found over a large part of
India and Ceylon, and not uncommon in collections,
has always been considered a true and independent
species, and no suspicions have been expressed regard-
ing it. But a male of this form does not, I believe,
exist. I have examined the fine series in the British
Museum, in the East India Company's Museum, in
the Hope Museum at Oxford, in Mr. Hewitson's and
several other private collections, and can find nothing
but females ; and for this common butterfly no male
partner can be found except the equally common P.
Pammon, a species already provided with two wives,
and yet to whom we shall be forced, I believe, to
assign a third. On carefully examining P. Romulus,

150 THE MALAYAN PAPILIONIDjE AS

I find that in all essential characters — the form and
texture of the wings, the length of the antennas, the
spotting of the head and thorax, and even the peculiar
tints and shades with which it is ornamented — it
corresponds exactly with the other females of the
Fammon group ; and though, from the peculiar mark-
ing of the fore wings, it has at first sight a very dif-
ferent aspect, yet a closer examination shows that
every one of its markings could be produced by slight
and almost imperceptible modifications of the various
allied forms. I fully believe, therefore, that I shall
be correct in placing P. Romulus as a third Indian
form of the female P. Pammon, corresponding to P.
Melanides, the third form of the Malayan P. Theseus.
I may mention here that the females of this group
have a superficial resemblance to the Polydorus group
of Papilios, as shown by P. Theseus having been con-
sidered to be the female of P. Antiphus, and by P.
Romulus being arranged next to P. Hector. There is
no close affinity between these two groups of Papilio,
and I am disposed to believe that we have here a
case of mimicry, brought about by the same causes
which Mr. Bates has so well explained in his account
of the Heliconidaa, and which has led to the singular
exuberance of polymorphic forms in this and allied
groups of the genus Papilio. I shall have to devote
a section of my essay to the consideration of this
subject.

The third example of polymorphism I have to bring
forward is Papilio Ormenus, which is closely allied

ILLUSTRATIVE OF NATURAL SELECTION. 151

to the well-known P. Erechtheus, of Australia. The
most common form of the female also resembles that
of P. Erechtheus ; but a totally different-looking in-
sect was found by myself in the Aru Islands, and
figured by Mr. Hewitson under the name of P. Ones-
imus, which subsequent observation has convinced me
is a second form of the female of P. Ormenus. Com-
parison of this with BoisduvaPs description of P.
Amanga, a specimen of which from New Guinea is
in the Paris Museum, shows the latter to be a closely
similar form ; and two other specimens were obtained
by myself, one in the island of Goram and the other in
Waigiou, all evidently local modifications of the same
form. In each of these localities males and ordinary
females of P. Ormenus were also found. So far there
is no evidence that these light- coloured insects are
not females of a distinct species, the males of which
have not been discovered. But two facts have con-
vinced me this is not the case. At Dorey, in New
Guinea, where males and ordinary females closely
allied to P. Ormenus occur (but which seem to me
worthy of being separated as a distinct species), I
found one of these light-coloured females closely fol-
lowed in her flight by three males, exactly in the same
manner as occurs (and, I believe, occurs only) with
the sexes of the same species. After watching them
a considerable time, I captured the whole of them, and
became satisfied that I had discovered the true rela-
tions of this anomalous form. The next year I had
corroborative proof of the correctness of this opinion

152 THE MALAYAN PAPILIONIDJE AS

by the discovery in the island of Batchian of a new
species allied to P. Ormenus, all the females of which,
either seen or captured by me, were of one form, and
much more closely resembling the abnormal light-
coloured females of P. Ormenus and P. Pandion than
the ordinary specimens of that sex. Every naturalist
will, I think, agree that this is strongly confirmative
of the supposition that both forms of female are of
one species ; and when we consider, further, that in
four separate islands, in each of which I resided for
several months, the two forms of female were obtained
and only one form of male ever seen, and that about
the same time, M. Montrouzier in Woodlark Island,
at the other extremity of New Guinea (where he
resided several years, and must have obtained all the
large Lepidoptera of the island), obtained females
closely resembling mine, which, in despair at finding
no appropriate partners for them, he mates with a
widely different species — it becomes, I think, suffi-
ciently evident this is another case of polymorphism
of the same nature as those already pointed out in
P. Pammon and P. Memnon. This species, however,
is not only dimorphic, but trimorphic ; for, in the
island of Waigiou, I obtained a third female quite
distinct from either of the others, and in some degree
intermediate between the ordinary female and the
male. The specimen is particularly interesting to
those who believe, with Mr. Darwin, that extreme
difference of the sexes has been gradually produced
by what he terms sexual selection, since it may be

ILLUSTRATIVE OF NATURAL SELECTION. 153

supposed to exhibit one of the intermediate steps in
that process, which has been accidentally preserved in
company with its more favoured rivals, though its
extreme rarity (only one specimen having been seen
to many hundreds of the other form) would indicate
that it may soon become extinct.

The only other case of polymorphism in the genus
Papilio, at all equal in interest to those I have now
brought forward, occurs in America; and we have,
fortunately, accurate information about it. Papilio
Turnus is common over almost the whole of tem-
perate North America ; and the female resembles the
male very closely. A totally different-looking insect
both in form and colour, Papilio Glaueus, inhabits the
same region ; and though, down to the time when
Boisduval published his " Species General," no con-
nexion was supposed to exist between the two species,
it is now well ascertained that P. Glaucus is a second
female form of P. Turnus. In the " Proceedings
of the Entomological Society of Philadelphia," Jan.,
1863, Mr. Walsh gives a very interesting account of
the distribution of this species. He tells us that in
the New England States and in New York all the
females are yellow, while in Illinois and further south
all are black; in the intermediate region both black
and yellow females occur in varying proportions.
Lat. 37° is approximately the southern limit of the
yellow form, and 42° the northern limit of the black
form ; and, to render the proof complete, both black
and yellow insects have been bred from a single batch

154 THE MALAYAN PAPILIONIDJE AS

of eggs. He further states that, out of thousands
of specimens, he has never seen or heard of inter-
mediate varieties between these forms. In this in-
teresting example we see the effects of latitude in
determining the proportions in which the individuals
of each form should exist. The conditions are here
favourable to the one form, tJiere to the other ; but
we are by no means to suppose that these conditions
consist in climate alone. It is highly probable that
the existence of enemies, and of competing forms of
life, may be the main determining influences; and
it is much to be wished that such a competent ob-
server as Mr. Walsh would endeavour to ascertain
what are the adverse causes which are most efficient
in keeping down the numbers of each of these con-
trasted forms.

Dimorphism of this kind in the animal kingdom
does not seem to have any direct relations to the
reproductive powers, as Mr. Darwin has shown to
be the case in plants, nor does it appear to be very
general. One other case only is known to me in
another family of my eastern Lepidoptera, the Pier-
idas ; and but few occur in the Lepidoptera of other
countries. The spring and autumn broods of some
European species differ very remarkably; and this
must be considered as a phenomenon of an analo-
gous though not of an identical nature, while the
Araschnia prorsa, of Central Europe, is a striking
example of this alternate or seasonal dimorphism.
Among our nocturnal Lepidoptera, I am informed,

ILLUSTRATIVE OF NATURAL SELECTION. 155

many analogous cases occur ; and as the whole
history of many of these has been investigated by
breeding successive generations from the egg, it is
to be hoped that some of our British Lepidopterists
will give us a connected account of all the abnormal
phenomena which they present. Among the Coleop-
tera Mr. Pascoe has pointed out the existence of two
forms of the male sex in seven species of the two
genera Xenocerus and Mecocerus belonging to the
family Anthribidae, (Proc. Ent. Soc. Lond., 1862);
and no less than six European Water-beetles, of the
genus Dytiscus, have females of two forms, the most
common having the elytra deeply sulcate, the rarer
smooth as in the males. The three, and sometimes
four or more, forms under which many Hymenop-
cerous insects (especially Ants) occur, must be con-
sidered as a related phenomenon, though here each
form is specialized to a distinct function in the
economy of the species. Among the higher animals,
albinoism and melanism may, as I have already stated,
be considered as analogous facts ; and I met with
one case of a bird, a species of Lory (Eos fuscata),
clearly existing under two differently coloured forms,
since I obtained both sexes of each from a single
flock, while no intermediate specimens have yet been
found.

The fact of the two sexes of one species differing
very considerably is so common, that it attracted but
little attention till Mr. Darwin showed how it could
in many cases be explained by the principle of

156 THE MALAYAN PAPILIONIDJE A3

sexual selection. For instance, in most polygamous
animals the males fight for the possession of the
females, and the victors, always becoming the pro-
genitors of the succeeding generation, impress upon
their male offspring their own superior size, strength,
or unusually developed offensive weapons. It is thus
that we can account for the spurs and the superior
strength and size of the males in Gallinaceous birds,
and also for the large canine tusks in the males of
fruit-eating Apes. So the superior beauty of plumage
and special adornments of the males of so many birds
can be explained by supposing (what there are many
facts to prove) that the females prefer the most beau-
tiful and perfect-plumaged males, and that thus, slight
accidental variations of form and colour have been
accumulated, till they have produced the wonderful
train of the Peacock and the gorgeous plumage of
the Bird of Paradise. Both these causes have no
doubt acted partially in insects, so many species
possessing horns and powerful jaws in the male sex
only, and still more frequently the males alone re-
joicing in rich colours or sparkling lustre. But there
is here another cause which has led to sexual differ-
ences, viz., a special adaptation of the sexes to diverse
habits or modes of life. This is well seen in female
Butterflies (which are generally weaker and of slower
flight), often having colours better adapted to con-
cealment; and in certain South American species (Pa-
pilio torquatus) the females, which inhabit the forests,
resemble the JEneas group of Papilios which abound

ILLUSTRATIVE OF NATURAL SELECTION. 157

in similar localities, while the males, which frequent
the sunny open river-banks, have a totally different
colouration. In these cases, therefore, natural selec-
tion seems to have acted independently of sexual
selection ; and all such cases may be considered as
examples of the simplest dimorphism, since the off-
spring never offer intermediate varieties between the
parent forms.

The phenomena of dimorphism and polymorphism
may be well illustrated by supposing that a blue-eyed,
flaxen-haired Saxon man had two wives, one a black-
haired, red-skinned Indian squaw, the other a woolly-
headed, sooty-skinned negress — and that instead of the
children being mulattoes of brown or dusky tints,
mingling the separate characteristics of their parents
in varying degrees, all the boys should be pure Saxon
boys like their father, while the girls should altogether
resemble their mothers. This would be thought a
sufficiently wonderful fact ; yet the phenomena here
brought forward as existing in the insect-world are
still more extraordinary ; for each mother is capable
not only of producing male offspring like the father,
and female like herself, but also of producing other
females exactly like her fellow-wife, and altogether
differing from herself. If an island could be stocked
with a colony of human beings having similar phy-
siological idiosyncrasies with Papilio Pammon or
Papilio Ormenus, we should see white men living
with yellow, red, and black women, and their off-
spring always reproducing the same types ; so that

158 THE MALAYAN PAPILIOXIDE AS

at the end of many generations the men would remain
pure white, and the women of the same well-marked
races as at the commencement.

The distinctive character therefore of dimorphism
is this, that the union of these distinct forms does
not produce intermediate varieties, but reproduces the
distinct forms unchanged. In simple varieties, on the
other hand, as well as when distinct local forms or
distinct species are crossed, the offspring never re-
sembles either parent exactly, but is more or less in-
termediate between them. Dimorphism is thus seen to
be a specialized result of variation, by which new phy-
siological phenomena have been developed ; the two
should therefore, whenever possible, be kept separate.

3. Local form, or variety. — This is the first step in
the transition from variety to species. It occurs in
species of wide range, when groups of individuals have
become partially isolated in several points of its area
of distribution, in each of which a characteristic form
has become more or less completely segregated. Such
forms are very common in all parts of the world, and
have often been classed by one author as varieties, by
another as species. I restrict the term to those cases
where the difference of the forms is very slight, or
where the segregation is more or less imperfect. The
best example in the present group is Papilio Agamem-
non, a species which ranges over the greater part of
tropical Asia, the whole of the Malay archipelago,
and a portion of the Australian and Pacific regions.
The modifications are principally of size and form,

ILLUSTRATIVE OF NATURAL SELECTION. 159

and, though slight, are tolerably constant in each local-
ity. The steps, however, are so numerous and gradual
that it would be impossible to define many of them,
though the extreme forms are sufficiently distinct. Pa-
pilio Sarpedon presents somewhat similar but less nu-
merous variations.

4. Co-existing Variety. — This is a somewhat doubtful
case. It is when a slight but permanent and heredi-
tary modification of form exists in company with the
parent or typical form, without presenting those inter-
mediate gradations which would constitute it a case
of simple variability. It is evidently only by direct
evidence of the two forms breeding separately that this
can be distinguished from dimorphism. The difficulty
occurs in Papilio Jason, and P. Evemon, whioh in-
habit the same localities, and are almost exactly alike
in form, size, and colouration, except that the latter
always wants a very conspicuous red spot on the under
surface, which is found not only in P. Jason, but in all
the allied species. It is only by breeding the two in-
sects that it can be determined whether this is a case of
a co-existing variety or of dimorphism. In the former
case, however, the difference being constant and so very
conspicuous and easily defined, I see not how we could
escape considering it as a distinct species. A true case
of co-existing forms would, I consider, be produced, if
a slight variety had become fixed as a local form, and
afterwards been brought into contact with the parent
species, with little or no intermixture of the two ; and
such instances do very probably occur.

160 THE MALAYAN PAPILIONIDM AS

5. Race or subspecies. — These are local forms com-
pletely fixed and isolated ; and there is no possible test
but individual opinion to determine which of them shall
be considered as species and which varieties. If sta-
bility of form and " the constant transmission of some
characteristic peculiarity of organization " is the test of
a species (and I can find no other test that is more
certain than individual opinion) then every one of
these fixed races, confined as they almost always are
to distinct and limited areas, must be regarded as a
species ; and as such I have in most cases treated them.
The various modifications of Papilio Ulysses, P. Peran-
thus, P. Codrus, P. Eurypilus, P. Helenus, &c., are
excellent examples; for while some present great and
well-marked, others offer slight and inconspicuous dif-
ferences, yet in all cases these differences seem equally
fixed and permanent. If, therefore, we call some of
these forms species, and others varieties, we introduce a
purely arbitrary distinction, and shall never be able to
decide where to draw the line. The races of Papilio
Ulysses, for example, vary in amount of modification
from the scarcely differing New Guinea form to those
of Woodlark Island and New Caledonia, but all seem
equally constant ; and as most of these had already
been named and described as species, I have added the
New Guinea form under the name of P. Autolycus.
We thus get a little group of Ulyssine Papilios, the
whole comprised within a very limited area, each one
confined to a separate portion of that area, and, though
differing in various amounts, each apparently constant.

ILLUSTRATIVE OF NATUEAL SELECTION. 161

Few naturalists will doubt that all these may and pro-
bably have been derived from a common stock, and
therefore it seems desirable that there should be a unity
in our method of treating them ; either call them all
varieties or all species. Varieties, however, continually
get overlooked ; in lists of species they are often alto-
gether unrecorded ; and thus we are in danger of
neglecting the interesting phenomena of variation and
distribution which they present. I think it advisable,
therefore, to name all such forms ; and those who will
not accept them as species may consider them as sub-
species or races.

6. Species. — Species are merely those strongly
marked races or local forms which when in contact
do not intermix, and when inhabiting distinct areas
are generally believed to have had a separate origin,
and to be incapable of producing a fertile hybrid
offspring. But as the test of hybridity cannot be
applied in one case in ten thousand, and even if it
could be applied would prove nothing, since it is
founded on an assumption of the very question to 'be
decided — and as the test of separate origin is in every
case inapplicable — and as, further, the test of non-
intermixture is useless, except in those rare cases
where the most closely allied species are found in-
habiting the same area, it will be evident that we
have no means whatever of distinguishing so-called
"true species" from the several modes of variation
here pointed out, and into which they so often pass
by an insensible gradation. It is ouite true that, in

21

162 THE MALAYAN PAPILIONIDJE AS

the great majority of cases, what we term " species "
are so well marked and definite that there is no dif-
ference of opinion about them ; but as the test of a
true theory is, that it accounts for, or at the very
least is not inconsistent with, the whole of the phe-
nomena and apparent anomalies of the problem to be
solved, it is reasonable to ask that those who deny
the origin of species by variation and selection should
grapple with the facts in detail, and show how the
doctrine of the distinct origin and permanence of
species will explain and harmonize them. It has been
recently asserted by Dr. J. E. Gray (in the Proceed-
ings of the Zoological Society for 1863, page 134),
that the difficulty of limiting species is in proportion
to our ignorance, and that just as groups or countries
are more accurately known and studied in greater
letail the limits of species become settled. This state-
ment has, like many other general assertions, its por-
tion of both truth and error. There is no doubt that
many uncertain species, founded on few or isolated
specimens, have had their true nature determined by
the study of a good series of examples : they have
been thereby established as species or as varieties ;
and the number of times this has occurred is doubtless
very great. But there are other, and equally trust-
worthy cases, in which, not single species, but whole
groups have, by the study of a vast accumulation of
materials, been proved to have no definite specific
limits. A few of these must be adduced. In Dr.
Carpenter's " Introduction to the Study of the Fora-

ILLUSTRATIVE OF NATURAL SELECTION. 163

minifera," he states that "there is not a single specimen
of plant or animal of which the range of variation has
been studied by the collocation and comparison of so
large a number of specimens as have passed under the
review of Messrs. Williamson) Parker, Rupert Jones, and
myself, in our studies of the types of this group ; " and
the result of this extended comparison of specimens
is stated to be, " The range of variation is so great
among the Foraminifera as to include not merely those
differential characters ivhicli have been usually accounted
SPECIFIC, but also those upon which the greater part
of the GENERA of this group have been founded, and even
in some instances those of its ORDERS " (Foraminifera,
Preface, x). Yet this same group had been divided
by D'Orbigny and other authors into a number of
clearly defined families, genera, and species, which these
careful and conscientious researches have shown to
have been almost all founded on incomplete knowledge.
Professor DeCandolle has recently given the results
of an extensive review of the species of Cupuliferas.
He finds that the best-known species of oaks are those
which produce most varieties and subvarieties ; that
they are often surrounded by provisional species ;
and, with the fullest materials at his command, two-
thirds of the species he considers more or less doubt-
ful. His general conclusion is, that (i in botany the
lowest series of groups, SUBVARIETIES, VARIETIES, and
RACES are very badly limited; these can be grouped into
SPECIES a little less vaguely limited, which again can
be formed into sufficiently precise GENERA.." This

M 2

164 THE MALAYAN PAPILIONID& AS

general conclusion is entirely objected to by the writer
of the article in the " Natural History Review," who,
however, does not deny its applicability to the par-
ticular order under discussion, while this very differ-
ence of opinion is another proof that difficulties in
the determination of species do not, any more than
in the higher groups, vanish with increasing mate-
rials and more accurate research.

Another striking example of the same kind is seen
in the genera Rubus and Rosa, adduced by Mr.
Darwin himself; for though the amplest materials
exist for a knowledge of these groups, and the most
careful research has been bestowed upon them, yet
the various species have not thereby been accurately
limited and defined so as to satisfy the majority of
botanists. In Mr. Baker's revision of the British
Roses, just published by the Linnsean Society, the
author includes under the single species Rosa canina,
no less than twenty-eight named varieties, distin-
guished by more or less constant characters and often
confined to special localities ; and to these are referred
about seventy of the species of Continental and British
botanists.

Dr. Hooker seems to have found the same thing
in his study of the Arctic flora. For though he has
had much of the accumulated materials of his pre-
decessors to work upon, he continually expresses him-
self as unable to do more than group the numerous
and apparently fluctuating forms into more or less im-
perfectly defined species. In his paper on the "Dis-

ILLUSTRATIVE OF NATURAL SELECTION. 165

tribution of Arctic Plants," (Trans. Linn. Soc. xxiii.,
p. 310) Dr. Hooker says: — "The 'most able and ex-
perienced descriptive botanists vary in their estimate
of the value of the f specific term ' to a much greater
extent than is generally supposed." . . "I think
I may safely affirm that the * specific term ' has three
different standard values, all current in descriptive
botany, but each more or less confined to one class
of observers." . . u This is no question of what
is right or wrong as to the real value of the spe-
cific term ; I believe each is right according to the
standard he assumes as the specific."

Lastly, I will adduce Mr. Bates's researches on the
Amazons. During eleven years he accumulated vast
materials, and carefully studied the variation and dis-
tribution of insects. Yet he has shown that many
species of Lepidoptera, which before offered no special
difficulties, are in reality most intricately combined
in a tangled web of affinities, leading by such gradual
steps from the slightest and least stable variations to
fixed races and well-marked species, that it is very
often impossible to draw those sharp dividing-lines
which it is supposed that a careful study and full
materials will always enable us to do.

These few examples show, I think, that in every
department of nature there occur instances of the in-
stability of specific form, which the increase of mate
rials aggravates rather than diminishes. And it must
be remembered that the naturalist is rarely likely to
err on the side of imputing greater indefiniteness to

166 THE MALAYAN PAPILIONIDJE AS

species than really exists. There is a completeness
and satisfaction to the mind in denning and limiting
and naming a species, which leads us all to do so
whenever we conscientiously -can, and which we know
has led many collectors to reject vague intermediate
forms as destroying the symmetry of their cabi-
nets. We must therefore consider these cases of ex-
cessive variation and instability as being thoroughly
well established ; and to the objection that, after all,
these cases are but few compared with those in which
species can be limited and defined, and are therefore
merely exceptions to a general rule, I reply that a
true law embraces all apparent exceptions, and that
to the great laws of nature there are no real excep-
tions— that what appear to be such are equally results
of law, and are often (perhaps indeed always) those
very results which are most important as revealing
the true nature and action of the law. It is for such
reasons that naturalists now look upon the study of
varieties as more important than that of well-fixed
species. It is in the former that we see nature still
at work, in the very act of producing those wonderful
modifications of form, that endless variety of colour,
and that complicated harmony of relations, which
gratify every sense and give occupation to every
faculty of the true lover of nature.

Variation as specially influenced by Locality.

The phenomena of variation as influenced by locality
have not hitherto received much attention. Botanists,

ILLUSTRATIVE OF NATURAL SELECTION. 167

ifc is true, are acquainted with the influences of climate,
altitude, and other physical conditions, in modifying
the forms and external characteristics of plants ; but
I am not aware that any peculiar influence has been
traced to locality, independent of climate. Almost
the only case I can find recorded is mentioned in
that repertory of natural-history facts, " The Origin
of Species," viz. that herbaceous groups have a ten-
dency to become arboreal in islands. In the animal
world, I cannot find that any facts have been pointed
out as showing the special influence of locality in
giving a peculiar fades to the several disconnected
species that inhabit it. What I have to adduce on
this matter will therefore, I hope, possess some in-
terest and novelty.

On examining the closely allied species, local forms,
and varieties distributed over the Indian and Malayan
regions, I find that larger or smaller districts, or even
single islands, give a special character to the majority
of their Papilionidse. For instance : 1. The species
of the Indian region (Sumatra, Java, and Borneo)
are almost invariably smaller than the allied species
inhabiting Celebes and the Moluccas ; 2. The species
of New Guinea and Australia are also, though in a
less degree, smaller than the nearest species or va-
rieties of the Moluccas ; 3. In the Moluccas them-
selves the species of Amboyna are the largest; 4.
The species of Celebes equal or even surpass in size
those of Amboyna; 5. The species and varieties of
Celebes possess a striking character in the form of

1G8 THE MALAYAN PAPILIONIDJE AS

the anterior wings, different from that of the allied
species and varieties of all the surrounding islands ;
6. Tailed species in India or the Indian region become
tailless as they spread eastward through the archi-
pelago ; 7. In Amboyna and Ceram the females of
several species are dull -coloured, while in the adjacent
islands they are more brilliant.

Local variation of Size. — Having preserved the finest
and largest specimens of Butterflies in my own col-
lection, and having always taken for comparison the
largest specimens of the same sex, I believe that the
tables I now give are sufficiently exact. The differences
of expanse of wings are in most cases very great, and
are much more conspicuous in the specimens themselves
than on paper. It will be seen that no less than four-
teen Papilionida3 inhabiting Celebes and the Moluccas
are from one- third to one-half greater in extent of wing
than the allied species representing them in Java, Su-
matra, and Borneo. Six species inhabiting Amboyna
are larger than the closely allied forms of the northern
Moluccas and New Guinea by about one-sixth. These
include almost every case in which closely allied
species can be compared.

Species of Papilionidae of the Closely allied species of Java and

Moluccas and Celebes (large). the Indian region (small).

Expanse. Expanse.

Inches. Inches.

Ornithoptera Helena f O. Pompeus 5'8

Amboyna) 7 '6 { O. Amphrisius 6'0

Papilio Adamantius

(Celebes) 5'8

P. Lorquinianus (Mo-
luccas) 4'8

P. Peranthus 3'8

ILLUSTRATIVE OF NATURAL SELECTION.

169

Species of Papilionidce of the
Moluccas and Celebes (large).

Expanse.
Inches.

P. Blumei (Celebes) ... 5-4
P. Alphenor( Celebes)... 4'8
P. Gigon (Celebes) ... 5'4
P. Deucalion ( Celebes)... 4-6
P. Agamemnon, var.

(Celebes) 4'4

P. Eurypilus (Moluccas) 4'0
P. Telephus (Celebes)... 4-3
P. JEgisthus (Moluccas) 4'4
P. Milon (Celebes) ... 4'4
P. Androcles (Celebes)... 4'8
P. Polyphontes (Celebes) 4'6
Leptocircus Ennius

(Celebes) 2'0

Species inhabiting Ainboyna
(large).

Papilio Ulysses

P. Polydorus

P. Deiphobus

P. Gambrisius

P. Codrus

Ornithoptera Priamus,
(male)

6-1

4-9

6-8

6-4
5-1

8-3

Closely allied species of Java and
the Indian region (small).

Expanse.
Inches.

P. Brama , ... 4'0

P. Theseus 3-6

P. Demolion 4-0

P. Macareus 37

P. Agamemnon, var. ... 38
P. Jason... .. 3-4

P. Rama

P. Sarpedon ..
P. Antiphates
P. Diphilus ..

3-2
3-8
3-7
3-9

L. Meges 1-8

Allied species of New Guinea and
the North Moluccas (smaller).

P. Autolycus 52

P. Telegonus

P. Leodamas

P. Deiphontes

P. Ormenus

P. Tydeus

P. Codrus, var. papu-

ensis

Ornitnoptera Poseidon,

(male)

4-0
4-0
5-8
5-6
6-0

4-3
7-0

Local variation of Form. — The differences of form are
equally clear. Papilio Pammon everywhere on the con-
tinent is tailed in both sexes. In Java, Sumatra, and
Borneo, the closely allied P. Theseus has a very short
tail, or tooth only, in the male, while in the females the
tail is retained. Further east, in Celebes and the South
Moluccas, the hardly separable P. Alphenor has quite

170 THE MALAYAN PAPILIONID2E A3

lost the tail in the male, while the female retains it, but
in a narrower and less spatulate form. A little further,
in Gilolo, P. Nicanor has completely lost the tail in
both sexes.

Papilio Agamemnon exhibits a somewhat similar
series of changes. In India it is always tailed; in
the greater part of the archipelago it has a very short
tail ; while far east, in New Guinea and the adjacent
islands, the tail has almost entirely disappeared.

In the Polydorus-group two species, P. Antiphus
^and P. Diphilus, inhabiting India and the Indian
region, are tailed, while the two which take their
place in the Moluccas, New Guinea, and Australia,
P. Polydorus and P. Leodamas, are destitute of tail,
the species furthest east having lost this ornament
the most completely.

Western species, Tailed. Allied Eastern species not Tailed.

Papilio Pammon (India) ... P. Thesus (Islands) minute tail.

P. Agamemnon, var. (India) P. Agamemnon, var. (Islands).

P. Antiphus (India, Java) ... P. Polydorus (Moluccas).

P. Diphilus (India, Java) ... P. Leodamas (New Guinea).

The most conspicuous instance of local modification
of form, however, is exhibited in the island of Celebes,
which in this respect, as in some others, stands alone
and isolated in the whole archipelago. Almost every
species of Papilio inhabiting Celebes has the wings
of a peculiar shape, which distinguishes them at a
glance from the allied species of every other island.
This peculiarity consists, first, in the upper wings
being generally more elongate and falcate ; and se-

ILLUSTRATIVE OF' NATURAL SELECTION. Ill

condly, in the costa or anterior margin being much
more curved, and in most instances exhibiting near
the base an abrupt bend or elbow, which in some
species is very conspicuous. This peculiarity is visible,
not only when the Celebesian species are compared
with their small- sized allies of Java and Borneo, but
also, and in an almost equal degree, when the large
forms of A.mboyna and the Moluccas are the objects
of comparison, showing that this is quite a distinct
phenomenon from the difference of size which has just
been pointed out.

In the following Table I have arranged the chief
Papilios of Celebes in the order in which they exhibit
this characteristic form most prominently.

Papilios of Celebes, having the Closely allied Papilios of the sur-
wings falcate or with abruptly rounding islands, with less falcate

curved costa. wings and slightly curved costa.

1. P. Gigon P. Demotion (Java).

2. P. Pamphylus P. Jason (Sumatra).

3. P. Milon P. Sarpedon (Moluccas, Java).

4. P. Agamemnon, var. ... P. Agamemnon, var. (Borneo).

5. P. Adamantius P. Peranthus (Java).

6. P. Ascalaphus P. Deiphontes (Gilolo).

7. P. Sataspes P. Helenus (Java).

8. P. Blumei P. Brama (Sumatra).

9. P. Androcles P. Anfciphates (Borneo).

10. P. Rhesus P. Aristseus (Moluccas).

11. P. Theseus, var. (male) ... P. Thesus (male) (Java).

12. P. Codrus, var P. Codrus (Moluccas).

13. P. Encelades P. Leucothoe (Malacca).

It thus appears that every species of Papilio exhibits
this peculiar form in a greater or less degree, except
one, P. Polyphontes, allied to P. Diphilus of India

172

THE MALAYAN PAPILIONID3Z AS

and P. Polydorus of the Moluccas. This fact I shall
recur to again, as I think it helps us to understand
something of the causes that may have brought about
the phenomenon we are considering. Neither do the
genera Ornithoptera and Leptocircus exhibit any traces
of this peculiar form. In several other families of
Butterflies this characteristic form reappears in a few
species. In the Pieridse the following species, all
peculiar to Celebes, exhibit it distinctly : —
1. Pieris Eperia compared with P. Coronis (Java).

2. Thyca Zebuda

3. T. Rosenbergii

4. Tachyris Hombronii ...

5. T. Lycaste

6. T. Zarinda

7. T. Ithome

8. Eronia tritsea

9 Iphias Glaucippe, var.

Thyca Descombesi
(India).

T. Hyparete (Java).

T. Lyncida.

T. Lyncida.

T. Nero (Malacca).

T. Nephele.

Ercnia Valeria
(Java).

Iphias Glaucippe
(Java).

The species of Terias, one or two Pieris, and the genus
Callidryas do not exhibit any perceptible change of
form.

In the other families there are but few similar
examples. The following are all that I can find in my
collection : —

Cethosia ^Eole ... compared with Cethosia Biblis (Java).
Eurhinia megalonice „ „ Eurhinia Polynice

(Borneo).
Limenitis Limire ... „ „ Limenitis Procris

(Java).
Cynthia Arsinoe, var. „ „ Cynthia Arsinoe (Java,

Sumatra, Borneo)

ILLUSTEATIVE OF NATURAL SELECTION. 173

All these belong to the family of the Nymphalidse.
Many other genera of this family, as Diadema, Adolias,
Charaxes, and Cyrestis, as well as the entire families
of the Danaidse, SatyridaB, Lycsenidse, and Hesperidse,
present no examples of this peculiar form of the upper
wing in the Celebesian species.

Local variations of Colour. — In Amboyna and Ceram
the female of the large and handsome Ornithoptera
Helena has the large patch on the hind wings con-
stantly of a pale dull ochre or buff colour, while in
the scarcely distinguishable varieties from the adjacent
islands of Bouru and New Guinea, it is of a golden
yellow, hardly inferior in brilliancy to its colour in
the male sex. The female of Ornithoptera Priamus
(inhabiting Amboyna and Ceram exclusively) is of a
pale dusky brown tint, while in all the allied species the
same sex is nearly black with contrasted white mark-
ings. As a third example, the female of Papilio Ulysses
has the blue colour obscured by dull and dusky tints,
while in the closely allied species from the surrounding
islands, the females are of almost as brilliant an azure
blue as the males. A parallel case to this is the occur-
rence, in the small islands of Goram, Matabello, Ke,
and Aru, of several distinct species of Euplasa and
Diadema, having broad bands or patches of white,
which do not exist in any of the allied species from
the larger islands. These facts seem to indicate some
local influence in modifying colour, as unintelligible
and almost as remarkable as that which has resulted
in the modifications of form previously described.

17 '-! THE MALAYAN PAP1LIONID1E AS

Remarks on the facts of Local variation.

The facts now brought forward seem to me of the
highest interest. We see that almost all the species
in two important families of the Lepidoptera (Papi-
lionidse and Pieridse) acquire, in a single island, a
characteristic modification of form distinguishing them
from the allied species and varieties of all the sur-
rounding islands. In other equally extensive families
no such change occurs, except in one or two isolated
species. However we may account for these pheno-
mena, or whether we may be quite unable to account
for them, they furnish, in my opinion, a strong cor-
roborative testimony in favour of the doctrine of the
origin of species by successive small variations ; for
we have here slight varieties, local races, and un-
doubted species, all modified in exactly the same
manner, indicating plainly a common cause producing
identical results. On the generally received theory
of the original distinctness and permanence of species,
we are met by this difficulty : one portion of these
curiously modified forms are admitted to have been
produced by variation and some natural action of local
conditions ; whilst the other portion, differing from
the former only in degree, and connected with them
by insensible gradations, are said to have possessed
this peculiarity of form at their first creation, or to
have derived it from unknown causes of a totally dis-
tinct nature. Is not the a priori evidence in favour
of an identity of the causes that have produced such

ILLUSTRATIVE OF NATURAL SELECTION. 175

similar results ? and have we not a right to call upon
our opponents for some proofs of their own doctrine,
and for an explanation of its difficulties, instead of
their assuming that they are right, and laying upon
us the burthen of disproof?

Let us now see if the facts in question do not them-
selves furnish some clue to their explanation. Mr.
Bates has shown that certain groups of butterflies have
a defence against insectivorous animals, independent
of swiftness of motion. These are generally very
abundant, slow, and weak fliers, and are more or less
the objects of mimicry by other groups, which thus
gain an advantage in a freedom from persecution
similar to that enjoyed by those they resemble. Now
the only Papilios which have not in Celebes acquired
the peculiar form of wing, belong to a group which is
imitated both by other species of Papilio and by
Moths of the genus Epicopeia. This group is of weak
and slow flight; and we may therefore fairly conclude
that it possesses some means of defence (probably in
a peculiar odour or taste) which saves it from attack.
Now the arched costa and falcate form of wing is gener-
ally supposed to give increased powers of flight, or, as
seems to me more probable, greater facility in making
sudden turnings, and thus baffling a pursuer. But the
members of the Polydorus-group (to which belongs
the only unchanged Celebesian Papilio), being already
guarded against attack, have no need of this increased
power of wing ; and " natural selection " would there-
fore have no tendency to produce it. The whole family

176 1HE MALAYAN PAPILIONIDJE AS

of DanaidaB are in the same position : they are slow
and weak fliers ; yet they abound in species and indi-
viduals, and are the objects of mimicry. The Satyrida)
have also probably a means of protection — perhaps their
keeping always near the ground and their generally
obscure colours ; while the Lyca3nida3 and Hesperidse
may find security in their small size and rapid motions.
In the extensive family of the Nymphalida3, however,
we find that several of the larger species, of com-
paratively feeble structure, have their wings modified
(Cethosia, Limenitis, Junonia, Cynthia), while the large-
bodied powerful species, which have all an excessively
rapid flight, have exactly the same form of wing in
Celebes as in the other islands. On the whole, there-
fore, we may say that all the butterflies of rather large
size, conspicuous colours, and not very swift flight have
been affected in the manner described, while the smaller
sized and obscure groups, as well as those which are
the objects of mimicry, and also those of exceedingly
swift flight have remained unaffected.

It would thus appear as if there must be (or once
have been) in the island of Celebes, some peculiar
enemy to these larger-sized butterflies which does not
exist, or is less abundant, in the surrounding islands.
Increased powers of flight, or rapidity of turning, was
advantageous in baffling this enemy ; and the peculiar
form of wing necessary to give this would be readily
acquired by the action of " natural selection" on the
slight variations of form that are continually occurring.

Such an enemy one would naturally suppose to be

ILLUSTRATIVE OF NATURAL SELECTION. 177

an insectivorous bird ; but it is a remarkable fact that
most of the genera of Fly-catchers of Borneo and Java
on the one side (Muscipeta, Philentoma,) and of the
Moluccas on the other (Monarcha, Ehipidura), are
almost entirely absent from Celebes. Their place seems
to be supplied by the Caterpillar-catchers (Grauca-
lus, Campephaga, &c.), of which six or seven species
are known from Celebes and are very numerous in
individuals. We have no positive evidence that these
birds pursue butterflies on the wing, but it is highly
probable that they do so when other food is scarce.
Mr. Bates has suggested to me that the larger Dragon-
flies (^Eshna, &c.) prey upon butterflies ; but I did not
notice that they were more abundant in Celabes than
elsewhere. However this may be, the fauna of Celebes
is undoubtedly highly peculiar in every department of
which we have any accurate knowledge ; and though we
may not be able satisfactorily to trace how it has been
effected, there can, I think, be little doubt that the
singular modification in the wings of so many of the
butterflies of that island is an effect of that complicated
action and reaction of all living things upon each other
in the struggle for existence, which continually tends
to readjust disturbed relations, and to bring every
species into harmony with the varying conditions of
the surrounding universe.

But even the conjectural explanation now given fails
us in the other cases of local modification. Why the
species of the Western islands should be smaller than
those further east, — why those of Amboyna should

IT

178 THE MALAYAN PAPILIONIDJE AS

exceed in size those of Gilolo and New Guinea — why
the tailed species of India should begin to lose that
appendage in the islands, and retain no trace of it on
the borders of the Pacific, — and why, in three separate
cases, the females of Amboyna species should be less
gaily attired than the corresponding females of the
surrounding islands, — are questions which we cannot
at present attempt to answer. That they depend, how-
ever, on some general principle is certain, because ana-
logous facts have been observed in other parts of the
world. Mr. Bates informs me that, in three distinct
groups, Papilios which on the Upper Amazon and in
most other parts of South America have spotless upper
wings obtain pale or white spots at Para and on the
Lower Amazon ; and also that the ^Eneas-group of Pa-
pilios never have tails in the equatorial regions and the
Amazons valley, but gradually acquire tails in many
cases as they range towards the northern or southern
tropic. Even in Europe we have somewhat similar
facts ; for the species and varieties of butterflies peculiar
to the island of Sardinia are generally smaller and more
deeply coloured than those of the mainland, and the
same has recently been shown to be the case with the
common tortoiseshell butterfly in the Isle of Man ;
while Papilio Hospiton, peculiar to the former island,
has lost the tail, which is a prominent feature of the
closely allied P. Machaon.

Facts of a similar nature to those now brought for-
ward would no doubt be found to occur in other
groups of insects, were local faunas carefully studied in

ILLUSTRATIVE OF NATUEAL SELECTION. 179

relation to those of the surrounding countries ; and
they seem to indicate that climate and other physical
causes have, in some cases, a very powerful effect in
modifying specific form and colour, and thus directly
aid in producing the endless variety of nature.

Mimicry,

Having fully discussed this subject in the preceding
essay, I have only to adduce such illustrations of it, as
are furnished by the Eastern Papilionidae, and to show
their bearing upon the phenomena of variation already
mentioned. As in America, so in the Old "World,
species of Danaidse are the objects which the other
families most often imitate. But besides these, some
genera of Morphida3 and one section of the genus
Papilio are also less frequently copied. Many species
of Papilio mimic other species of these three groups so
closely that they are undistinguishable when on the
wing ; and in every case the pairs which resemble
each other inhabit the same locality.

The following list exhibits the most important and
best marked cases of mimicry which occur among the
Papilionidse of the Malayan region and India : —

Mimickers. Species mimicked. Common habitat.

1. Papilio paradoxa Euplcea Midamusl

(male & female) (male & female) J bumatra> «0.

2. P. Catmus ...

3. P. Thule ...
4. P. Macareus

... E. Rhadamanthus .

... Danais sobrina ...
... D. Aglaia

Borneo and Su-
matra.
New Guinea.
Malacca, Java.

N 2

180 THE MALAYAN PAPILIONIDJE AS

Mimickers. Species mimicked. Common habitat.

5. Papilio Agestor. . .

6. P. Idseoides ...

7. P. Delessertii ...

Danais Tytia. . .
Hestia Leuconoe
Idcopsis daos

Northern India-
Philippines.
Penang.

8. P. Pandion (fe-

male) Brasilia bioculata . New Guinea.

PAPILIO (PoLYDORUs- and Coosr-groups).

9. P. Pammon (Ro-

mulus, female)... Papilio Hector .., India.

10. P. Theseus, var.

(female) P. Antiphus Sumatra,Bornco.

11. P. Theseus, var.

(female) P. Diphilus Sumatra, Java.

12. P. Memnon, var.

(Achates, female) P. Coon Sumatra.

13. P. Androgeus,var.

(Achates, female) P. Doubledayi ... Northern India.

14. P. (Enomaus (fe-

male) P. Liris Timor.

We have, therefore, fourteen species or marked varie-
ties of Papilio, which so closely resemble species of
other groups in their respective localities, that it is not
possible to impute the resemblance to accident. The
first two in the list (Papilio paradoxa and P. Caunus)
are so exactly like Euploea Midamus and E. Rhadaman-
thus on the wing, that although they fly very slowly, I
was quite unable to distinguish them. The first is a
very interesting case, because the male and female differ
considerably, and each mimics the corresponding sex
of the Euploea. A new species of Papilio which I
discovered in New Guinea resembles Danais sobrina,

ILLUSTRATIVE OF NATURAL SELECTION. 181

from the same country, just as Papilio Marcareus re-
sembles Danais Aglaia in Malacca, and (according to
Dr. Horsfield's figure) still more closely in Java. The
Indian Papilio Agestor closely imitates Danais Tytia,
which has quite a different style of colouring from the
preceding; and the extraordinary Papilio Idaeoides
from the Philippine Islands, must, when on the wing,
perfectly resemble the Hestia Leuconoe of the same
region, as also does the Papilio Delessertii imitate
the Ideopsis daos from Penang. Now in every one of
these cases the Papilios are very scarce, while the
DanaidaB which they resemble are exceedingly abun-
dant— most of them swarming so as to be a positive
nuisance to the collecting entomologist by continually
hovering before him when he is in search of newer and
more varied captures. Every garden, every roadside,
the suburbs of every village are full of them, indicating
very clearly that their life is an easy one, and that
they are free from persecution by the foes which keep
down the population of less favoured races. This
superabundant population has been shown by Mr.
Bates to be a general characteristic of all American
groups and species which are objects of mimicry ; and
it is interesting to find his observations confirmed by
examples on the other side of the globe.

The remarkable genus Drusilla, a group of pale-
coloured butterflies, more or less adorned with ocellate
spots, is also the object of mimicry by three distinct
genera (Melanitis, Hyantis, and Papilio). These in-
sects, like the Danaidse, are abundant in individuals,

182 THE MALAYAN PAP1LIONIDJZ AS

have a very weak and slow flight, and do not seek
concealment, or appear to have any means of protec-
tion from insectivorous creatures. It is natural to
conclude, therefore, that they have some hidden pro-
perty which saves them from attack ; and it is easy
to see that when any other insects, by what we call
accidental variation, come more or less remotely to
resemble them, the latter will share to some extent in
their immunity. An extraordinary dimorphic form of
the female of Papilio Ormenus has come to resemble
the Drusillas sufficiently to be taken for one of that
group at a little distance ; and it is curious that I cap-
tured one of these Papilios in the Aru Islands hovering
along the ground, and settling on it occasionally, just
as it is the habit of the Drusillas to do. The resem-
blance in this case is only general ; but this form of
Papilio varies much, and there is therefore material
for natural selection to act upon, so as ultimately to
produce a copy as exact as in the other cases.

The eastern Papilios allied to Polydorus, Coon,
and Philoxenus, form a natural section of the genus
resembling, in many respects, the ^Eneas-group of
South America, which they may be said to represent
in the East. Like them, they are forest insects,
have a low and weak flight, and in their favourite
localities are rather abundant in individuals ; and like
them, too, they are the objects of mimicry. We may
conclude, therefore, that they possess some hidden
means of protection, which makes it useful to other
insects to be mistaken for them.

ILLUSTRATIVE OF NATURAL SELECTION. 183

The Papilios which resemble them belong to a very
distinct section of the genus, in which the sexes differ
greatly ; and it is those females only which differ most
from the males, and which have already been alluded
to as exhibiting instances of dimorphism, which resem-
ble species of the other group.

The resemblance of P. Romulus to P. Hector is,
in some specimens, very considerable, and has led to
the two species being placed following each other in
the British Museum Catalogues and by Mr. E. Double-
day. I have shown, however, that P. Romulus is
probably a dimorphic form of the female P. Pammon,
and belongs to a distinct section of the genus.

The next pair, Papilio Theseus, and P. Antiphus,
have been united as one species both by De Haan
and in the British Museum Catalogues. The ordi-
nary variety of P. Theseus found in Java almost as
nearly resembles P. Diphilus, inhabiting the same
country. The most interesting case, however, is the
extreme female form of P. Memnon (figured by Cramer
under the name of P. Achates), which has acquired
the general form and markings of P. Coon, an insect
which differs from the ordinary male P. Memnon,
as much as any two species which can be chosen
in this extensive and highly varied genus; and, as
if to show that this resemblance is not accidental,
but is the result of law, when in India we find a
species closely allied to P. Coon, but with red instead
of yellow spots (P. Doubledayi), the corresponding
variety of P. Androgeus (P. Achates, Cramer, 182,

181 THE MALAYAN PAPILIONIDJE AS

A, B,) has acquired exactly the same peculiarity of
having red spots instead of yellow. Lastly, in the
island of Timor, the female of P. (Enomaus (a species
allied to P. Memnon) resembles so closely P. Liris
(one of the Polydorus-group), that the two, which
were often seen flying together, could only be distin-
guished by a minute comparison after being captured.

The last six cases of mimicry are especially instruc-
tive, because they seem to indicate one of the pro-
cesses by which dimorphic forms have been produced.
When, as in these cases, one sex differs much from
the other, and varies greatly itself, it may happen
that occasionally individual variations will occur having
a distant resemblance to groups which are the objects
of mimicry, and which it is therefore advantageous to
resemble. Such a variety will have a better chance of
preservation ; the individuals possessing it will be mul-
tiplied ; and their accidental likeness to the favoured
group will be rendered permanent by hereditary trans-
mission, and, each successive variation which increases
the resemblance being preserved, and all variations
departing from the favoured type having less chance
of preservation, there will in time result those singular
cases of two or more isolated and fixed forms, bound
together by that intimate relationship which consti-
tutes them the sexes of a single species. The reason
why the females are more subject to this kind of
modification than the males is, probably, that their
slower flight, when laden with eggs, and their exposure
to attack while in the act of depositing their eggs

ILLUSTRATIVE OF NATURAL SELECTION. 185

upon leaves, render it especially advantageous for
them to have some additional protection. This they
at once obtain by acquiring a resemblance to other
species which, from whatever cause, enjoy a compara-
tive immunity from persecution.

Concluding remarks on Variation in Lepidoptera.

This summary of the more interesting phenomena
of variation presented by the eastern Papilionidse is,
I think, sufficient to substantiate my position, that
the Lepidoptera are a group that offer especial faci-
lities for such inquiries ; and it will also show that
they have undergone an amount of special adaptive
modification rarely equalled among the more highly
organized animals. And, among the Lepidoptera, the
great and pre-eminently tropical families of Papilionida3
and Danaida3 seem to be those in which complicated
adaptations to the surrounding organic and inorganic
universe have been most completely developed, offer-
ing in this respect a striking analogy to the equally
extraordinary, though totally different, adaptations
which present themselves in the Orchidea?, the only
family of plants in which mimicry of other organisms
appears to play any important part, and the only one
in which cases of conspicuous polymorphism occur ; for
as such we must class the male, female, and hermaph-
rodite forms of Catasetum tridentatum, which differ so
greatly in form and structure that they were long con-
sidered to belong to three distinct genera.

18G THE MALAYAN PAPIL10NIDJE AS

Arrangement and Geographical Distribution of the
Malayan Papilionidce.

Arrangement. — Although the species of Papilionidaa
inhabiting the Malayan region are very numerous,
they all belong to three out of the nine genera into
which the family is divided. One of the remaining
genera (Eurycus) is restricted to Australia, and another
(Teinopalpus) to the Himalayan Mountains, while no
less than four (Parnassius, Doritis, Thais, and Seri-
cinus) are confined to Southern Europe and to the
mountain-ranges of the Palaearctic region.

The genera Ornithoptera and Leptocircus are highly
characteristic of Malayan entomology, but are uniform
in character and of small extent. The genus Papilio,
on the other hand, presents a great variety of forms,
and is so richly represented in the Malay Islands, that
more than one-fourth of all the known species are
found there. It becomes necessary, therefore, to divide
this genus into natural groups before we can success-
fully study its geographical distribution.

Owing principally to Dr. Horsfield's observations
in Java, we are acquainted with a considerable number
of the larvae of Papilios ; and these furnish good char-
acters for the primary division of the genus into na-
tural groups. The manner in which the hinder wings
are plaited or folded back at the abdominal margin, the
size of the anal valves, the structure of the antennae,
and the form of the wings are also of much service,
as well as the character of the flight and the style of

ILL USTEA TIVE OF NA T UEAL SELECTION. 187

colouration. Using these characters, I divide the
Malayan Papilios into four sections, and seventeen
groups, as follows : —

Genus OENITHOPTEEA.

a. Priamus-group. 1 ,

c. Brookeanus-group. j Black and ^een'

b. Pompeus-group. Black and yellow.

Genus PAPILIO.

A. Larvae short, thick, with numerous fleshy tubercJes ;

of a purplish colour.

a. Nox-group. Abdominal fold in male very large ;

anal valves small, but swollen ; antennae mode-
rate ; wings entire, or tailed ; includes the Indian
Philoxenus - group .

b. Coon-group. Abdominal fold in male small ; anal

valves small, but swollen; antennas moderate;
wings tailed.

c. Polydorus-group. Abdominal fold in male small,

or none; anal valves small or obsolete, hairy;
wings tailed or entire.

B. Larvae with third segment swollen, transversely or

obliquely banded ; pupa much bent. Imago with
abdominal margin in male plaited, but not re-
flexed ; body weak ; antennae long ; wings much
dilated, often tailed.

d. Ulysses-group.

Protenor - group (Indian) is

e. Peranthus-group.

f. Memnon-group.

somewhat intermediate be-
tween these, and is nearest

to the Nox-group.
g. Helenus-group.
h. Erectheus-group.
i. Pammon-group.
k. Demolion-group.

C. Larvae subcylindrical, variously coloured. Imago with
abdominal margin in male plaited, but not re-
flexed ; body weak ; antennas short, with a thick
curved club; wings entire.

188 THE MALAYAN PAPILIONIDJE AS

1. Erithonius-group. Sexes alike, larva and pupa
something like those of P. Demotion.

m. Paradoxa-group. Sexes different.

n. Dissimilis - group. Sexes alike ; larva bright -
coloured; pupa straight, cylindric.

D. Larvae elongate, attenuate behind, and often bifid, with
lateral and oblique pale stripes, green. Imago
with the abdominal margin in male reflexed,
woolly or hairy within ; anal valves small, hairy ;
antennas short, stout ; body stout.

o. Macareus -group. Hind wings entire.

p. Antiphates-group. Hind wings much tailed (swal-
low-tails).

q. Eurypylus-group. Hind wings elongate or tailed.

Genus LEPTOCIRCTJS.

Making, in all, twenty distinct groups of Malayan
Papilionidae.

The first section of the genus Papilio (A) comprises
insects which, though differing considerably in struc-
ture, having much general resemblance. They all have
a weak, low flight, frequent the most luxuriant forest-
districts, seem to love the shade, and are the objects
of mimicry by other Papilios.

Section B consists of weak-bodied, large-winged in-
sects, with an irregular wavering flight, and which,
when resting on foliage, often expand the wings, which
the species of the other sections rarely or never do.
They are the most conspicuous and striking of eastern
Butterflies.

Section C consists of much weaker and slower-flying
insects, often resembling in their flight, as well as in
their colours, species of Danaida3.

ILLUSTRATIVE OF NATURAL SELECTION. 189

Section D contains the strongest-bodied and most
swift-flying of the genus. They love sunlight, and
frequent the borders of streams and the edges of
puddles, where they gather together in swarms con-
sisting of several species, greedily sucking up the
moisture, and, when disturbed, circling round in the
air, or flying high and with great strength and
rapidity.

Geographical Distribution. — One hundred and thirty
species of Malayan PapilionidjB are now known within
the district extending from the Malay peninsula, on
the north-west, to Woodlark Island, near New Guinea,
on the south-east.

The exceeding richness of the Malayan region in
these fine insects is seen by comparing the number
of species found in the different tropical regions of the
earth. From all Africa only 33 species of Papilio are
known ; but as several are still undescribed in collec-
tions, we may raise their number to about 40. In all
tropical Asia there are at present described only 65
species, and I have seen in collections but two or three
which have not yet been named. In South America,
south of Panama, there are 150 species, or about one-
seventh more than are yet known from the Malayan
region ; but the area of the two countries is very dif-
ferent ; for while South America (even excluding Pata-
gonia) contains 5,000,000 square miles, a line encircling
the whole of the Malayan islands would only include an
area of 2,700,000 square miles, of which the land-area
would be about 1,000,000 square miles. This superior

190 THE MALAYAN PAPILIONIDJE A3

richness is partly real and partly apparent. The break-
ing up of a district into small isolated portions, as
in an archipelago, seems highly favourable to the segre-
gation and perpetuation of local peculiarities in certain
groups ; so that a species which on a continent might
have a wide range, and whose local forms, if any,
would be so connected together that it would be im-
possible to separate them, may become by isolation
reduced to a number of such clearly defined and con-
stant forms that we are obliged to count them as
species. From this point of view, therefore, the
greater proportionate number of Malayan species may
be considered as apparent only. Its true superiority
is shown, on the other hand, by the possession of
three genera and twenty groups of Papilionidas against
a single genus and eight groups in South America,
and also by the much greater average size of the Ma-
layan species. In most other families, however, the
reverse is the case, the South American Nymphalida3,
Satyridse, and ErycinidaB far surpassing those of the
East in number, variety, and beauty.

The following list, exhibiting the range and distri-
bution of each group, will enable us to study more
easily their internal and external relations.

Range of the Groups of Malayan Papilionidce.
Ornithoptera.

1. Prianms - group. Moluccas to Woodlark

Island 5 species.

2. Pompeus • group. Himalayas to New

Guinea, (Celebes, maximum) ... ... 11 ,,

3. Brookeana- group. Sumatra and Borneo... 1 „

ILLUSTRATIVE OF NATURAL SELECTION. 191

Papilio.

4. Nox-group. North India, Java, and Philip-

pines ... ... ... ... ... ... 5 species.

5. Coon-gronp. North India to Java 2 „

6. Poly dorus- group. India to New Guinea

and Pacific 7 ,,

7. Ulysses-group. Celebes to New Caledonia 4 „

8. Peranthus - group. India to Timor and

Moluccas (India, maximum) 9 „

9. Memnon-group. India to Timor and Mo-

luccas (Java, maximum) ... ... ... 10 ,,

10. Helenus- group. Africa and India to New

Guinea 11 „

11. Pammon-group. India to Pacific and Aus-

tralia 9 .,

12. Erectheus-group. Celebes to Australia ... 8 „

13. Demolion-group. India to Celebes ... 2 „

14. Erithonius-group. Africa, India, Australia 1 „

15. Paradoxa-group. India to Java (Borneo,

maximum) 5 .,

16. Dissimilis-group. India to Timor (India,

maximum) 2 „

17. Macareus-group. India to New Guinea ... 10 „

18. Antiphates-group. Widely distributed ... 8 „

19. Eurypylus-group. India to Australia ... 15 „

Leptocircus.

20 Leptocircus -group. India to Celebes ... 4 „

This Table shows the great affinity of the Malayan
with the Indian Papilionidge, only three out of the
nineteen groups ranging beyond, into Africa, Europe,
or America. The limitation of groups to the Indo-
Malayan or Austro- Malay an divisions of the archi-
pelago, which is so well marked in the higher animals,
is much less conspicuous in insects, but is shown in
some degree by the Papilionidas. The following groups

192 THE MALAYAN PAPILIONIDJE AS

are either almost or entirely restricted to one portion
of the archipelago : —

IndO'Malayan Region. Austro-Malayan Region.

Nox-group. Priamus- group.

Coon-group. Ulysses -group.

Macareus-group (nearly). Erechtheus-group.

Par adoxa - group .
Dissimilis-group (nearly).
Broo keanus - group .
LEPTOCIECTJS (genus),

The remaining groups, which range over the whole
archipelago, are, in many cases, insects of very power-
ful flight, or they frequent open places and the sea-
beach, and are thus more likely to get blown from
island to island. The fact that three such character-
istic groups as those of Priamus, Ulysses, and Erech-
theus are strictly limited to the Australian region of
the archipelago, while five other groups are with equal
strictness confined to the Indian region, is a strong
corroboration of that division which has been founded
almost entirely on the distribution of Mammalia and
Birds.

If the various Malayan islands have undergone
recent changes of level, and if any of them have been
more closely united within the period of existing
species than they are now, we may expect to find
indications of such changes in community of species
between islands now widely separated ; while those
islands which have long remained isolated would have
had time to acquire peculiar forms by a slow and
natural process of modification.

ILLUSTRATIVE OF NATURAL SELECTION. 193

An examination of the relations of the species of
the adjacent islands, will thus enable us to correct
opinions formed from a mere consideration of their
relative positions. For example, looking at a map of
the archipelago, it is almost impossible to avoid the
idea that Java and Sumatra have been recently united;
their present proximity is so great, and they have
such an obvious resemblance in their volcanic struc-
ture. Yet there can be little doubt that this opinion
is erroneous, and that Sumatra has had a more recent
and more intimate connexion with Borneo than it has
had with Java. This is strikingly shown by the mam-
mals of these islands — very few of the species of Java
and Sumatra being identical, while a considerable
number are common to Sumatra and Borneo. The
birds show a somewhat similar relationship ; and we
shall find that the distribution of the Papilionidas tells
exactly the same tale. Thus : —

Sumatra has... 21 species"!

-g 30 20 sp. common to both islands;

Sumatra „ ... 21 „ }

j oo I SP* common to both islands ;

Borneo ., ... 30 „ ]

9o 20 sp. common to both islands ;

showing that both Sumatra and Java have a much
closer relationship to Borneo than they have to each
other — a most singular and interesting result, when we
consider the wide separation of Borneo from them both,
and its very different structure. The evidence fur-
nished by a single group of insects would have had

o

104 THE MALAYAN PAPILIONIDJE AS

but little weight on a point of such magnitude if
standing alone ; but coming as it does to confirm
deductions drawn from whole classes of the higher
animals, it must be admitted to have considerable
value.

We may determine in a similar manner the relations
of the different Papuan Islands to New Guinea. Of
thirteen species of PapilionidaB obtained in the Aru
Islands, six were also found in New Guinea, and
seven not. Of nine species obtained at Waigiou, six
were New Guinea, and three not. The five species
found at Mysol were all New Guinea species. Mysol,
therefore, has closer relations to New Guinea than
the other islands ; and this is corroborated by the
distribution of the birds, of which I will only now
give one instance. The Paradise Bird found in Mysol
is the common New Guinea species, while the Aru
Islands and Waigiou have each a species peculiar to
themselves.

The large island of Borneo, which contains more
species of Papilionidas than any other in the archi-
pelago, has nevertheless only three peculiar to itself;
and it is quite possible, and even probable, that one
of these may be found in Sumatra or Java. The last-
named island has also three species peculiar to it;
Sumatra has not one, and the peninsula of Malacca
only two. The identity of species is even greater
than in birds or in most other groups of insects, and
points very strongly to a recent connexion of the
whole with each other and the continent.

ILLUSTRATIVE OF NATURAL. SELECTION. 195

Remarkable Peculiarities of the Island of Celebes.

If we now pass to the next island (Celebes), sepa-
rated from those last mentioned by a strait not wider
than that which divides them from each other, we
have a striking contrast; for with a total number
of species less than either Borneo or Java, no fewer
than eighteen are absolutely restricted to it. Further
east, the large islands of Ceram and New Guinea have
only three species peculiar to each, and Timor has
five. We shall have to look, not to single islands,
but to whole groups, in order to obtain an amount
of individuality comparable with that of Celebes. For
example, the extensive group comprising the large
islands of Java, Borneo, and Sumatra, with the penin-
sula of Malacca, possessing altogether 48 species, has
about 24, or just half, peculiar to it; the numerous-
group of the Philippines possess 22 species, of which
17 are peculiar; the seven chief islands of the Moluccas
have 27, of which 12 are peculiar ; and the whole
of the Papuan Islands, with an equal number of species,
have 17 peculiar. Comparable with the most isolated
of these groups is Celebes, with its 24 species, of
which the large proportion of 18 are peculiar. We
see, therefore, that the opinion I have elsewhere ex-
pressed, of the high degree of isolation and the remark-
able distinctive features of this interesting island, is
fully borne out by the examination of this conspi-
cuous family of insects. A single straggling island
with a few small satellites, it is zoologically of equal

o 2

106 THE MALAYAN PAPIL10XIDM AS

importance with extensive groups of islands many
times as large as itself ; and standing in the very centre
of the archipelago, surrounded on every side with islets
connecting it with the larger groups, and which seem
to afford the greatest facilities for the migration and
intercommunication of their respective productions, it
yet stands out conspicuous with a character of its own
in every department of nature, and presents peculiari-
ties which are, I believe, without a parallel in any
similar locality on the globe.

Briefly to summarize these peculiarities, Celebes
possesses three genera of mammals (out of the very
small number which inhabit it) which are of singular
and isolated forms, viz., Cynopithecus, a tailless Ape
allied to the Baboons ; Anoa, a straight-horned Ante-
lope of obscure affinities, but quite unlike anything
else in the whole archipelago or in India : and Babi-
rusa, an altogether abnormal wild Pig. With a rather
limited bird population, Celebes has an immense pre-
ponderance of species confined to it, and has also six
remarkable genera (Meropogon, Ceycopsis, Strepto-
citta, Enodes, Scissirostrum, and Megacephalon) en-
tirely restricted to its narrow limits, as well as two
others (Prioniturus and Basilornis) which only range
to a single island beyond it.

Mr. Smith's elaborate tables of the distribution of
Malayan Hymenoptera (see " Proc. Linn. Soc." Zool.
vol. vii.) show that out of the large number of 301
species collected in Celebes, 190 (or nearly two-thirds)
are absolutely restricted to it, although Borneo on one

ILLUSTRATIVE OF NATURAL SELECTION. }<Jj

side, and the various islands of the Moluccas on the
other, were equally well explored by me ; and no less
than twelve of the genera are not found in any other
island of the archipelago. I have shown in the present
essay that, in the Papilionidre, it has far more species of
its own than any other island, and a greater proportion
of peculiar species than many of the large groups of
islands in the archipelago — and that it gives to a large
number of the species and varieties which inhabit it,
1st, an increase of size, and, 2nd, a peculiar modifica-
tion in the form of the wings, which stamp upon the
most dissimilar insects a mark distinctive of their
common birth-place.

What, I would ask, are we to do with phenomena
such as these? Are we to rest content with that very
simple, but at the same time very unsatisfying expla-
nation, that all these insects and other animals were
created exactly as they are, and originally placed ex-
actly where they are, by the inscrutable will of their
Creator, and that we have nothing to do but to register
the facts and wonder ? Was this single island selected
for a fantastic display of creative power, merely to ex-
cite a childlike and unreasoning admiration ? Is all
this appearance of gradual modification by the action of
natural causes — a modification the successive steps of
which we can almost trace — all delusive ? Is this har-
mony between the most diverse groups, all presenting
analogous phenomena, and indicating a dependence
upon physical changes of which we have independent
evidence, all false testimony ? If I could think so, the

198 THE MALAYAN PAPILIONID^E AS

study of nature would have lost for me its greatest
charm. I should feel as would the geologist, if you
could convince him that his interpretation of the earth's
past history was all a delusion — that strata were never
formed in the primeval ocean, and that the fossils he so
carefully collects and studies are no true record of a
former living world, but were all created just as they
now are, and in the rocks where he now finds them.

I must here express my own belief that none of these
phenomena, however apparently isolated or insignificant,
can ever stand alone — that not the wing of a butterfly
can change in form or vary in colour, except in har-
mony with, and as a part of the grand march of nature.
I believe, therefore, that all the curious phenomena I
have just recapitulated, are immediately dependent on
the last series of changes, organic and inorganic, in
these regions ; and as the phenomena presented by the
island of Celebes differ from those of all the surround-
ing islands, it can, I conceive, only be because the past
history of Celebes has been, to some extent, unique and
different from theirs. We must have much more evi-
dence to determine exactly in what that difference has
consisted. At present, I only see my way clear to one
deduction, viz., that Celebes represents one of the oldest
parts of the archipelago ; that it has been formerly more
completely isolated both from India and from Australia
than it is now, and that amid all the mutations it has
undergone, a relic or substratum of the fauna and
flora of some more ancient land has been here pre-
served to us.

ILLUSTRATIVE OF NATURAL SELECTION. 199

It is only since my return home, and since I have
been able to compare the productions of Celebes side
by side with those of the surrounding islands, that I
have been fully impressed with their peculiarity, and
the great interest that attaches to them. The plants
and the reptiles are still almost unknown ; and it is to
be hoped that some enterprising naturalist may soon
devote himself to their study. The geology of the
country would also be well worth exploring, and its
newer fossils would be of especial interest as eluci-
dating the changes which have led to its present ano-
malous condition. This island stands, as it were, upon
the boundary-line between two worlds. On one side is
that ancient Australian fauna, which preserves to the
present day the facies of an early geological epoch ; on
the other is the rich and varied fauna of Asia, which
seems to contain, in every class and order, the most
perfect and highly organised animals. Celebes has
relations to both, yet strictly belongs to neither : it
possesses characteristics which are altogether its own ;
and I am convinced that no single island upon the
globe would so well repay a careful and detailed re-
search into its past and present history.

Concluding Remarks.

In writing this essay it has been my object to show
how much may, under favourable circumstances, be
learnt by the study of what may be termed the external
physiology of a small group of animals, inhabiting a
limited district. This branch of natural history had

200 THE MALAYAN PAPILIOXIDM, ETC.

received little attention till Mr. Darwin showed how
important an adjunct it may become towards a true
interpretation of the history of organized beings, and
attracted towards it some small share of that research
which had before been almost exclusively devoted to
internal structure and physiology. The nature of spe-
cies, the laws of variation, the mysterious influence
of locality on both form and colour, the phenomena of
dimorphism and of mimicry, the modifying influence
of sex, the general laws of geographical distribution,
and the interpretation of past changes of the earth's
surface, have all been more or less fully illustrated
by the very limited group of the Malayan Papilio-
nidso ; while, at the same time, the deductions drawn
therefrom have been shown to be supported by analo-
gous facts, occurring in other and often widely-sepa-
rated groups of animals.

201

V.
ON INSTINCT IN MAN AND ANIMALS.

THE most perfect and most striking examples of what
is termed instinct, those in which reason or observa-
tion appear to have the least influence, and which
seem to imply the possession of faculties farthest re-
moved from our own, are to be found among insects.
The marvellous constructive powers of bees and wasps,
the social economy of ants, the careful provision for
the safety of a progeny they are never to see mani-
fested by many beetles and flies, and the curious pre-
parations for the pupa state by the larvae of butterflies
and moths, are typical examples of this faculty, and
are supposed to be conclusive as to the existence of
some power or intelligence, very different from that
which we derive from our senses or from our reason.

How Instinct may be best Studied.

Whatever we may define instinct to be, it is evi-
dently some form of mental manifestation, and as we
can only judge of mind by the analogy of our own
mental functions and by observation of the results of
mental action in other men and in animals, it is in-
cumbent on us, first, to study and endeavour to com-
prehend the minds of infants, of savage men, and of

202 ON INSTINCT IN MAN AND ANIMALS.

animals not very far removed from ourselves, before
we pronounce positively as to the nature of the mental
operations in creatures so radically different from us
as insects. We have not yet even been able to ascer-
tain what are the senses they possess, or what relation
their powers of seeing, hearing, and feeling have to
ours. Their sight may far exceed ours both in delicacy
and in range, and may possibly give them knowledge
of the internal constitution of bodies analogous to that
which we obtain by the spectroscope ; and that their
visual organs do possess some powers which ours do
not, is indicated by the extraordinary crystalline rods
radiating from the optic ganglion to the facets of the
compound eye, which rods vary in form and thickness
in different parts of their length, and possess distinc-
tive characters in each group of insects. This complex
apparatus, so different from anything in the eyes of
vertebrates, may subserve some function quite incon-
ceivable by us, as well as that which we know as
vision. There is reason to believe that insects appre-
ciate sounds of extreme delicacy, and it is supposed
that certain minute organs, plentifully supplied with
nerves, and situated in the subcostal vein of the wing
in most insects, are the organs of hearing. But be-
sides these, the Orthoptera (such as grasshoppers,
&c.) have what are supposed to be ears on their fore
legs, and Mr. Lowne believes that the little stalked
balls, which are the sole remnants of the hind wings
in flies, are also organs of hearing or of some ana-
logous sense. In flies, too, the third joint of the

ON INSTINCT IN MAN AND ANIMALS. 203

antennae contains thousands of nerve-fibres, which
terminate in small open cells, and this Mr. Lowne
believes to be the organ of smell, or of some other,
perhaps new, sense. It is quite evident, therefore,
that insects may possess senses which give them a
knowledge of that which we can never perceive, and
enable them to perform acts which to us are incom-
prehensible. In the midst of this complete ignorance
of their faculties and inner nature, is it wise for us
to judge so boldly of their powers by a comparison
with our own ? How can we pretend to fathom the
profound mystery of their mental nature, and decide
what, and how much, they can perceive or remem-
ber, reason or reflect! To leap at one bound from
our own consciousness to that of an insect's, is as
unreasonable and absurd as if, with a pretty good
knowledge of the multiplication table, we were to
go straight to the study of the calculus of functions,
or as if our comparative anatomists should pass from
the study of man's bony structure to that of the fish,
and, without any knowledge of the numerous inter-
mediate forms, were to attempt to determine the homo-
logies between these distant types of vertebrata. In
such a case would not error be inevitable, and would
not continued study in the same direction only render
the .erroneous conclusions more ingrained and more
irremovable.

Definition of Instinct.
Before going further into this subject, we must

201 ON INSTINCT IN MAS AND ANIMALS.

determine what we mean by the term instinct. It
has been variously defined as — u disposition operating
without the aid of instruction or experience," " a
mental power totally independent of organization," or
"a power enabling an animal to do that which, in those
things man can do, results from a chain of reasoning,
and in things which man cannot do, is not to be ex-
plained by any efforts of the intellectual faculties."
We find, too, that the word instinct is very frequently
applied to acts which are evidently the result either
of organization or of habit. The colt or calf is said
to walk instinctively, almost as soon as it is born ;
but this is solely due to its organization, which ren-
ders walking both possible and pleasurable to it. So
we are said instinctively to hold out our hands to
save ourselves from falling, but this is an acquired
habit, which the infant does not possess. It appears
to me that instinct should be defined as — sc the per-
formance by an animal of complex acts, absolutely
without instruction or previously-acquired knowledge."
Thus, acts are said to be performed by birds in build-
ing their nests, by bees in constructing their cells,
and by many insects in providing for the future wants
of themselves or their progeny, without ever having
seen such acts performed by others, and without any
knowledge of why they perform them themselves.
This is expressed by the very common term " blind
instinct." But we have here a number of assertions
of matters of fact, which, strange to say, have never
been proved to be facts at all. They are thought to

Oy INSTINCT IN MAN AND ANIMALS. 205

be so self-evident that they may be taken for granted.
No one has ever yet obtained the eggs of some bird
which builds an elaborate nest, hatched these eggs by
steam or under a quite distinct parent, placed them
afterwards in an extensive aviary or covered garden,
where the situation and the materials of a nest simi-
lar to that of the parent birds may be found, and then
seen what kind of nest* these birds would build. If
under these rigorous conditions they choose the same
materials, the same situation, and construct the nest
in the same way and as perfectly as their parents did,
instinct would be proved in their case ; now it is only
assumed, and assumed, as I shall show further on,
without any sufficient reason. So, no one has ever
carefully taken the pupse of a hive of bees out of the
comb, removed them from the presence of other bees,
and loosed them in a large conservatory with plenty
of flowers and food, and observed what kind of cells
they would construct. But till this is done, no one
can say that bees build without instruction, no one
can say that with every new swarm there are no bees
older than those of the same year, who may be the
teachers in forming the new comb. Now, in a scien-
tific inquiry, a point which can be proved should not
be assumed, and a totally unknown power should not
be brought in to explain facts, when known powers
may be sufficient. For both these reasons I decline to
accept the theory of instinct in any case where all
other possible modes of explanation have not been
exhausted.

206 ON INSTINCT IN MAX AND ANIMALS.

Does Man possess Instincts.

Many of the upholders of the instinctive theory
maintain, that man has instincts exactly of the same
nature as those of animals, but more or less liable to
be obscured by his reasoning powers; and as this is
a case more open to our observation than any other,
I will devote a few pages to its consideration. Infants
are said to suck by instinct, and afterwards to walk
by the same power, while in adult man the most pro-
minent case of instinct is supposed to be, the powers
possessed by savage races to find their way across a
trackless and previously unknown wilderness. Let
us take first the case of the infant's sucking. It is
sometimes absurdly stated that the new-born infant
" seeks the breast," and this is held to be a wonderful
proof of instinct. No doubt it would be if true, but
unfortunately for the theory it is totally false, as
every nurse and medical man can testify. Still, the
child undoubtedly sucks without teaching, but this is
one of those simple acts dependent upon organization,
which cannot properly be termed instinct, any more
than breathing or muscular motion. Any object of
suitable size in the mouth of an infant excites the
nerves and muscles so as to produce the act of suction,
and when at a little later period, the will comes into
play, the pleasurable sensations consequent on the act
lead to its continuance. So, walking is evidently de-
pendent on the arrangement of the bones and joints,
and the pleasurable exertion of the muscles, which

ON INSTINCT IN MAN AND ANIMALS. 207

lead to the vertical posture becoming gradually the
most agreeable one ; and there can be little doubt
that an infant would learn of itself to walk, even if
suckled by a wild beast.

How Indians travel through unknown and trackless
Forests.

Let us now consider the fact, of Indians finding their
way through forests they have never traversed before.
This is much misunderstood, for I believe it is only
performed under such special conditions, as at once to
show that instinct has nothing to do with it. A savage,
it is true, can find his way through his native forests
in a direction in which he has never traversed them
before ; but this is because from infancy he has been
used to wander in them, and to find his way by in-
dications which he has observed himself or learnt from
others. Savages make long journeys in many direc-
tions, and, their whole faculties being directed to the
subject, they gain a wide and accurate knowledge
of the topography, not only of their own district,
but of all the regions round about. Every one who
has travelled in a new direction communicates his
knowledge to those who have travelled less, and de-
scriptions of routes and localities, and minute incidents
of travel, form one of the main staples of conversation
round the evening fire. Every wanderer or captive
from another tribe adds to the store of information,
and as the very existence of individuals and of whole
families and tribes, depends upon the completeness of

208 ON INSTINCT IN MAN AND ANIMALS.

this knowledge, all the acute perceptive faculties of
the adult savage are devoted to acquiring and perfect-
ing it. The good hunter or warrior thus comes to
know the bearing of every hill and mountain range,
the directions and junctions of all the streams, the
situation of each tract characterized by peculiar
vegetation, not only within the area he has himself
traversed, but for perhaps a hundred miles around
it. His acute observation enables him to detect
the slightest undulations of the surface, the various
changes of subsoil and alterations in the character of
the vegetation, that would be quite imperceptible to
a stranger. His eye is always open to the direction
in which he is going ; the mossy side of trees, the
presence of certain plants under the shade of rocks,
the morning and evening flight of birds, are to him
indications of direction, almost as sure as the sun in
the heavens. Now, if such a savage is required to
find his way across this country in a direction in
which he has never been before, he is quite equal
to the task. By however circuitous a route he has
come to the point he is to start from, he has observed
all the bearings and distances so well, that he knows
pretty nearly where he is, the direction of his own
home and that of the place he is required to go to.
He starts towards it, and knows that by a certain time
he must cross an upland or a river, that the streams
should flow in a certain direction, and that he should
cross some of them at a certain distance from their
sources. The nature of the soil throughout the whole

ON INSTINCT IN MAN AND ANIMALS. 209

region is known to him, as well as all the great fea-
tures of the vegetation. As he approaches any tract oi
country he has been in or near before, many minute
indications guide him, but he observes them so cau-
tiously that his white companions cannot perceive by
what he has directed his course. Every now and
then he slightly changes his direction, but he is never
confused, never loses himself, for he always feels at
home ; till at last he arrives at a well-known country,
and directs his course so as to reach the exact spot
desired. To the Europeans whom he guides, he seems
to have come without trouble, without any special ob-
servation, and in a nearly straight unchanging course.
They are astonished, and ask if he has ever been the
same route before, and when he answers "No," con-
clude that some unerring instinct could alone have
guided him. But take this same man into another
country very similar to his own, but with other streams
and hills, another kind of soil, with a somewhat dif-
ferent vegetation and animal life ; and after bringing
him by a circuitous route to a given point, ask him to
return to his starting place, by a straight line of fifty
miles through the forest, and he will certainly decline
to attempt it, or, attempting it, will more or less com-
pletely fail. His supposed instinct does not act out of
his own country.

A savage, even in a new country, has, however,
undoubted advantages, from his familiarity with forest
life, his entire fearlessness of being lost, his accurate
perception of direction and of distance, and he is thus

p

210 ON INSTINCT IN MAN AND ANIMALS.

able very soon to acquire a knowledge of the district
that seems marvellous to a civilized man ; but my own
observation of savages in forest countries has convinced
me, that they find their way by the use of no other
faculties than those which we ourselves possess. It
appears to me, therefore, that to call in the aid of a
new and mysterious power to account for savages
being able to do that which, under similar conditions,
we could almost all of us perform, although perhaps
less perfectly, is almost ludicrously unnecessary.

In the next essay I shall attempt to show, that much
of what has been attributed to instinct in birds, can be
also very well explained by crediting them with those
faculties of observation, memory, and imitation, and
with that limited amount of reason, which they un-
doubtedly exhibit.

211

VI.

THE PHILOSOPHY OF BIRDS' NESTS.

Instinct or Reason in the Construction of Birds' Nests.

BIRDS, we are told, build their nests by instinct, while
man constructs his dwelling by the exercise of reason.
Birds never change, but continue to build for ever on
the self-same plan ; man alters and improves his houses
continually. Reason advances ; instinct is stationary.

This doctrine is so very general that it may almost
be said to be universally adopted. Men who agree
on nothing else, accept this as a good explanation of
the facts. Philosophers and poets, metaphysicians and
divines, naturalists and the general public, not only
agree in believing this to be probable, but even adopt
it as a sort of axiom that is so self-evident as to need
no proof, and use it as the very foundation of their
speculations on instinct and reason. A belief so general,
one would think, must rest on indisputable facts, and
be a logical deduction from them. Yet I have come to
the conclusion that not only is it very doubtful, but
absolutely erroneous ; that it not only deviates widely
from the truth, but is in almost every particular exactly
opposed to it. I believe, in short, that birds do not
build their nests by instinct; that man does not con-

P 2

212 THE PHILOSOPHY OF BIRDS' NESTS.

struct his dwelling by reason ; that birds do change and
improve when affected by the same causes that make
men do so ; and that mankind neither alter nor improve
when they exist under conditions similar to those which
are almost universal among birds.

Do Men build by Reason or by Imitation?

Let us first consider the theory of reason, as alone
determining the domestic architecture of the human
race. Man, as a reasonable animal, it is said, con-
tinually alters and improves his dwelling. This I en-
tirely deny. As a rule, he neither alters nor improves,
any more than the birds do. What have the houses of
most savage tribes improved from, each as invariable as
the nest of a species of bird ? The tents of the Arab
are the same now as they were two or three thousand
years ago, and the mud villages of Egypt can scarcely
have improved since the time of the Pharoahs. The
palm-leaf huts and hovels of the various tribes of South
America and the Malay Archipelago, what have they
improved from since those regions were first inhabited ?
The Patagonian's rude shelter of leaves, the hollowed

O *

bank of the South African Earthmen, we cannot even
conceive to have been ever inferior to what they now
are. Even nearer home, the Irish turf cabin and the
Highland stone shelty can hardly have advanced much
during the last two thousand years. Now, no one
imputes this stationary condition of domestic archi-
tecture among these savage tribes to -instinct, but to
simple imitation from one generation to another, and

THE PHILOSOPHY OF BIEDS' NESTS. 213

the absence of any sufficiently powerful stimulus to
change or improvement. No one imagines that if an
infant Arab could be transferred to Patagonia or to
the Highlands, it would, when it grew up, astonish
its foster-parents by constructing a tent of skins. On
the other hand, it is quite clear that physical condi-
tions, combined with the degree of civilization arrived
at, almost necessitate certain types of structure. The
turf, or stones, or snow — the palm-leaves, bamboo, or
branches, which are the materials of houses in various
countries, are used because nothing else is so readily
to be obtained. The Egyptian peasant has none of
these, not even wood. What, then, can he use but
mud ? In tropical forest-countries, the bamboo and the
broad palm-leaves are the natural material for houses,
and the form and mode of structure will be decided
in part by the nature of the country, whether hot or
cool, whether swampy or dry, whether rocky or plain,
whether frequented by wild beasts, or whether subject
to the attacks of enemies. When once a particular
mode of building has been adopted, and has become
confirmed by habit and by hereditary custom, it will
be long retained, even when its utility has been lost
through changed conditions, or through migration into
a very different region. As a general rule, through-
out the whole continent of America, native houses are
built directly upon the ground — strength and security
being given by thickening the low walls and the roof.
In almost the whole of the Malay Islands, on the
contrary, the houses are raised on posts, often to a

214 THE PHILOSOPHY OF BIRDS' NESTS.

great height, with an open bamboo floor; and the
whole structure is exceedingly slight and thin. Now,
what can be the reason of this remarkable difference
between countries, many parts of which are strikingly
similar in physical conditions, natural productions, and
the state of civilization of their inhabitants ? We ap-
pear to have some clue to it in the supposed origin
and migrations of their respective populations. The
indigenes of tropical America are believed to have im-
migrated from the north — from a country where the
winters are severe, and raised houses with open floors
would be hardly habitable. They moved southwards
by land along the mountain ranges and uplands, and
in an altered climate continued the mode of construc-
tion of their forefathers, modified only by the new
materials they met with. By minute observations of
the Indians of the Amazon Valley, Mr. Bates arrived
at the conclusion that they were comparatively recent
immigrants from a colder climate. He says : — " No
one could live long among the Indians of the Upper
Amazon without being struck with their constitutional
dislike to the heat. . . Their skin is hot to the touch,
and they perspire little. . . They are restless and
discontented in hot, dry weather, but cheerful on cool
days, when the rain is pouring down their naked
backs." And, after giving many other details, he
concludes, " How different all this is with the Negro,
the true child of tropical climes ! The impression gra-
dually forced itself on my mind that the Red Indian
lives as an immigrant or stranger in these hot regions,

THE PHILOSOPHY OF BIRDS' NESTS. 215

and that his constitution was not originally adapted,
and has not since become perfectly adapted, to the
climate."

The Malay races, on the other hand, are no doubt
very ancient inhabitants of the hottest regions, and
are particularly addicted to forming their first settle-
ments at the mouths of rivers or creeks, or in land-
locked bays and inlets. They are a pre-eminently
maritime or semi-aquatic people, to whom a canoe is a
necessary of life, and who will never travel by land if
they can do so by water. In accordance with these
tastes, they have built their houses on posts in the
water, after the manner of the lake-dwellers of ancient
Europe ; and this mode of construction has become so
confirmed, that even those tribes who have spread far
into the interior, on dry plains and rocky mountains,
continue to build in exactly the same manner, and
find safety in the height to which they elevate their
dwellings above the ground.

Why does each Bird build a peculiar kind of Nest ?

These general characteristics of the abode of savage
man will be found to be exactly paralleled by the nests
of birds. Each species uses the materials it can most
readily obtain, and builds in situations most congenial
to its habits. The wren, for example, frequenting
hedgerows and low thickets, builds its nest generally of
moss, a material always found where it lives, and among
which it probably obtains much of its insect food ; but
it varies sometimes, using hay or feathers when these

216 THE PHILOSOPHY OF BIRDS' NESTS.

are at hand. Rooks dig in pastures and ploughed fields
for grubs, and in doing so must continually encounter
roots and fibres. These are used to line its nest. What
more natural ! The crow feeding on carrion, dead rab-
bits, and lambs, and frequenting sheep-walks and war-
rens, chooses fur and icool to line its nest. The lark
frequents cultivated fields, and makes its nest, on the
ground, of grass lined with Jiorsehair — materials the
most easy to meet with, and the best adapted to its
needs. The kingfisher makes its nest of the lones of
the fish which it has eaten. Swallows use clay and
mud from the margins of the ponds and rivers over
which they find their insect food. The materials of
birds' nests, like those used by savage man for his
house, are, then, those which come first to hand ; and
it certainly requires no more special instinct to select
them in one case than in the other.

But, it will be said, it is not so much the materials
as the form and structure of nests, that vary so much,
and are so wonderfully adapted to the wants and habits
of each species; how are these to be accounted for
except by instinct ? I reply, they may be in a great
measure explained by the general habits of the species,
the nature of the tools they have to work with, and the
materials they can most easily obtain, with the very
simplest adaptations of means to an end, quite within
the mental capacities of birds. The delicacy and per-
fection of the nest will bear a direct relation to the
size of the bird, its structure and habits. That of the
wren or the humming-bird is perhaps not finer or more

THE PHILOSOPHY OF J3IBDS' NESTS. 217

beautiful in proportion than that of the blackbird, the
magpie, or the crow. The wren, having a slender beak,
long legs, and great activity, is able with great ease to
form a well-woven nest of the finest materials, and
places it in thickets and hedgerows which it frequents
in its search for food. The titmouse, haunting fruit-
trees and walls, and searching in cracks and crannies for
insects, is naturally led to build in holes where it has
shelter and security ; while its great activity, and the
perfection of its tools (bill and feet), enable it readily
to form a beautiful receptable for its eggs and young.
Pigeons having heavy bodies and weak feet and bills (im-
perfect tools for forming a delicate structure) build rude,
flat nests of sticks, laid across strong branches which
will bear their weight and that of their bulky young.
They can do no better. The Caprimulgidae have the
most imperfect tools of all, feet that will not support
them except on a flat surface (for they cannot truly
perch) and a bill excessively broad, short, and weak, and
almost hidden by feathers and bristles. They cannot
build a nest of twigs or fibres, hair or moss, like other
birds, and they therefore generally dispense with one
altogether, laying their eggs on the bare ground, or
on the stump or flat limb of a tree. The clumsy hooked
bills, short necks and feet, and heavy bodies of Parrots,
render them quite incapable of building a nest like
most other birds. They cannot climb up a branch
without using both bill and feet ; they cannot even
turn round on a perch without holding on with their
bill. How, then, could they inlay, or weave, or twist

218 THE PHILOSOPHY OF BIRDS' NESTS.

the materials of a nest? Consequently, they all lay
in holes of trees, the tops of rotten stumps, or in
deserted ants' nests, the soft materials of which they
can easily hollow out.

Many terns and sandpipers lay their eggs on the
bare sand of the sea-shore, and no doubt the Duke of
Argyll is correct when he says, that the cause of
this habit is not that they are unable to form a nest,
but that, in such situations, any nest would be con-
spicuous and lead to the discovery of the eggs. The
choice of place is, however, evidently determined by
the habits of the birds, who, in their daily search
for food, are continually roaming over extensive tide-
washed flats. Gulls vary considerably in their mode of
nesting, but it is always in accordance with their struc-
ture and habits. The situation is either on a bare rock
or on ledges of sea-cliffs, in marshes or on weedy shores.
The materials are sea-weed, tufts of grass or rushes,
or the debris of the shore, heaped together with as
little order and constructive art as might be expected
from the webbed feet and clumsy bill of these birds,
the latter better adapted for seizing fish than for
forming a delicate nest. The long-legged, broad-billed
flamingo, who is continually stalking over muddy flats
in search of food, heaps up the mud into a conical
stool, on the top of which it lays its eggs. The bird
can thus sit upon them conveniently, and they are
kept dry, out of reach of the tides.

Now I believe that throughout the whole class of
birds the same general principles will be found to hold

THE PHILOSOPHY OF BIRDS' RESTS. 219

good, sometimes distinctly, sometimes more obscurely
apparent, according as the habits of the species are
more marked, or their structure more peculiar. It
is true that, among birds differing but little in struc-
ture or habits, we see considerable diversity in the
mode of nesting, but we are now so well assured that
important changes of climate and of surface have oc-
cured within the period of existing species, that it
is by no means difficult to see how such differences
have arisen. Simple habits are known to be here-
ditary, and as the area now occupied by each species
is different from that of every other, we may be sure
that such changes would act differently upon each, and
would often bring together species which had acquired
their peculiar habits in distinct regions and under
different conditions.

How do Young Birds learn to Build their First Nest?

But it is objected, birds do not learn to make their
nest as man does to build, for all birds will make
exactly the same nest as the rest of their species, even if
they have never seen one, and it is instinct alone that
can enable them to do this. JSTo doubt this would be
instinct if it were true, and I simply ask for proof
of the fact. This point, although so important to the
question at issue, is always assumed without proof, and
even against proof, for what facts there are, are op-
posed to it. Birds brought up from the egg in cages
do not make the characteristic nest of their species,
even though the proper materials are supplied them,

220 THE PHILOSOPHY OF BIRDS' NESTS.

and often make no nest at all, but rudely heap together
a quantity of materials ; and the experiment has never
been fairly tried, of turning out a pair of birds so
brought up, into an enclosure covered with netting,
and watching the result of their untaught attempts at
nest-making. With regard to the song of birds, how-
ever, which is thought to be equally instinctive, the
experiment has been tried, and it is found that young
birds never have the song peculiar to their species if
they have not heard it, whereas they acquire very
easily the song of almost any other bird with which
they are associated.

Do Birds sing by Instinct or by Imitation ?

The Hon. Daines Barrington has given an account of
his experiments in the "Philosophical Transactions " for
1773 (Vol. 63) ; he says : " I have educated nestling
linnets under the three best singing larks — the sky-
lark, woodlark, and titlark, every one of which, instead
of the linnet's song, adhered entirely to that of their
respective instructors. When the note of the titlark
linnet was thoroughly fixed, I hung the bird in a room
with two common linnets for a quarter of a year, which
were full in song ; the titlark linnet, however, did not
borrow any passage from the linnet's song, but adhered
stedfastly to that of the titlark." He then goes on to
say that birds taken from the nest at two or three weeks
old have already learnt the call-note of their species.
To prevent this the birds must be taken from the nest
when a day or two old, and he gives an account of a

THE PHILOSOPHY OF BIRDS' NESTS. 221

goldfinch which he saw at Knighton in Radnorshire, and
which sang exactly like a wren, without any portion of
the proper note of its species. This bird had been
taken from the nest at two or three days old, and had
been hung at a window opposite a small garden, where
it had undoubtedly acquired the notes of the wren
without having any opportunity of learning even the
call of the goldfinch.

He also saw a linnet, which had been taken from the
nest when only two or three days old, and which, not
having any other sounds to imitate, had learnt almost
to articulate, and could repeat.the words "Pretty Boy,"
and some other short sentences.

The Rev. W. H. Herbert made similar observations,
and states that the young whinchat and wheatear,
which have naturally little variety of song, are ready in
confinement, to learn from other species, and become
much better songsters. The bullfinch, whose natural
notes are weak, harsh, and insignificant, has never-
theless a wonderful musical faculty, since it can be
taught to whistle complete tunes. The nightingale, on
the other hand, whose natural song is so beautiful, is
exceedingly apt in confinement to learn that of other
birds instead. Bechstein gives an account of a redstart
which had built under the eaves of his house, which
imitated the song of a caged chaffinch, in a window
underneath, while another in his neighbour's garden
repeated some of the notes of a blackcap, which had a
nest close by.

These facts and many others which might be quoted,

222 THE PHILOSOPHY OF BIRDS NESTS.

render it certain .that the peculiar notes of birds
are acquired by imitation, as surely as a child learns
English or French, not by instinct, but by hearing the
language spoken by its parents.

It is especially worthy of remark that, for young
birds to acquire a new song correctly, they must be
taken out of hearing of their parents very soon, for
in the first three or four days they have already
acquired some knowledge of the parent notes, which
they will afterwards imitate. This shows that very
young birds can both hear and remember, and it would
be very extraordinary if, after they could see, they
could neither observe nor recollect, and could live for
days and weeks in a nest and know nothing of its
materials and the manner of its construction. During
the time they are learning to fly and return often to
the nest, they must be able to examine it inside and
out in every detail, and as we have seen that their
daily search for food invariably leads them among the
materials of which it is constructed, and among places
similar to that in which it is placed, is it so very
wonderful that when they want one themselves they
should make one like it? How else, in fact, should
they make it ? "Would it not be much more remark-
able if they went out of their way to get materials
quite different from those used in the parent nest,
if they arranged them in a way they had seen no
example of, and formed the whole structure differently
from that in which they themselves were reared, and
which we may fairly presume is that which their whole

THE PHILOSOPHY OF BIRDS' NESTS. 223

organization is best adapted to put together with cele-
rity and ease. It has, however, been objected that
observation, imitation, or memory, can have nothing
to do with a bird's architectural powers, because the
young birds, which in England are born in May or
June, will proceed in the following April or May to
build a nest as perfect and as beautiful as that in
which it was hatched, although it could never have
seen one built. But surely the young birds before they
left the nest had ample opportunities of observing its
form, its size, its position, the materials of which
it was constructed, and the manner in which those
materials were arranged. Memory would retain these
observations till the following spring, when the ma-
terials would come in their way during their daily
search for food, and it seems highly probable that the
older birds would begin building first, and that those
born the preceding summer would follow their ex-
ample, learning from them how the foundations of the
nest are laid and the materials put together. Again,
we have no right to assume that young birds gener-
ally pair together. It seems more probable that in
each pair there is frequently only one bird born the
preceding summer, who would be guided, to some ex-
tent, by its partner. At all events, till the crucial
experiment is made, and a pair of birds raised from
the egg, without ever seeing a nest, are shown to
be capable of making one exactly of the parental type,
I do not think we are justified in calling in the aid
of an unknown and mysterious faculty to do that

224 THE PHILOSOPHY OF BIRDS' RESTS.

which is so strictly analogous to the house-building of
savage man. In support of the view that birds learn
and improve in nest-building, it may be mentioned,
that the celebrated American observer, Wilson, strongly
insists on the variety in the nests of birds of the same
species, some being so much better finished than others ;
and he believes that the less perfect nests are built by the
younger , the more perfect by the older birds.

Again, we always assume that because a nest ap-
pears to us delicately and artfully built, that it there-
fore requires much special knowledge and acquired
skill (or their substitute, 'instinct) in the bird who
builds it. We forget that it is formed twig by twig
and fibre by fibre, rudely enough at first, but crevices
and irregularities, which must seem huge gaps and
chasms in the eyes of the little builders, are filled up
by twigs and stalks pushed in by slender beak and
active foot, and that the wool, feathers, or horsehair
are laid thread by thread, so that the result seems a
marvel of ingenuity to us, just as would the rudest
Indian hut to a native of Brobdignag.

Levaillant has given an account of the process of nest-
building by a little African warbler, which cufficiently
shows that a very beautiful structure may be produced
with very little art. The foundation was laid of moss
and flax interwoven with grass and tufts of cotton, and
presented a rude mass, five or six inches in diameter,
and four inches thick. This was pressed and trampled
down repeatedly, so as at last to make it into a kind of
felt. The birds pressed it with their bodies ; turning

THE PHILOSOPHY OF BIKDS' NESTS. 225

round upon them in every direction, so as to get it
quite firm and smooth before raising the sides. These
were added bit by bit, trimmed and beaten with the
wings and feet, so as to felt the whole together, pro-
jecting fibres being now and then worked in with the
bill. By these simple and apparently inefficient means,
the inner surface of the nest was rendered almost as
smooth and compact as a piece of cloth.

Man's Works mainly Imitative.

But look at civilised man ! it is said ; look at Grecian,
and Egyptian, and Roman, and Gothic, and modern Ar-
chitecture ! What advance ! what improvement ! what
refinements ! This is what reason leads to, whereas
birds remain for ever stationary. If, however, such
advances as these are required, to prove the effects of
reason as contrasted with instinct, then all savage and
many half-civilized tribes have no reason, but build in-
stinctively quite as much as birds do.

Man ranges over the whole earth, and exists under
the most varied conditions, leading necessarily to
equally varied habits. He migrates — he makes wars
and conquests — one race mingles with another — dif-
ferent customs are brought into contact — the habits of
a migrating or conquering race are modified by the
different circumstances of a new country. The civilized
race which conquered Egypt must have developed its
mode of building in a forest country where timber
was abundant, for it is not probable that the idea of
cylindrical columns originated in a country destitute

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226 THE PHILOSOPHY OF BIRDS' NESTS.

of trees. The pyramids might have been built by an
indigenous race, but not the temples of El Uksor and
Karnak. In Grecian architecture, almost every char-
acteristic feature can be traced to an origin in wooden
buildings. The columns, the architrave, the frieze, the
fillets, the cantelevers, the form of the roof, all point
to an origin in some southern forest-clad country, and
strikingly corroborate the view derived from philology,
that Greece was colonised from north-western India.
But to erect columns and span them with huge blocks
of stone or marble, is not an act of reason, but one
of pure unreasoning imitation. The arch is the only
true and reasonable mode of covering over wide spaces
with stone ; and therefore, Grecian architecture, how-
ever exquisitely beautiful, is false in principle, and is
by no means a good example of the application of
reason to the art of building. And what do most of
us do at the present day but imitate the buildings of
those that have gone before us ? We have not even
been able to discover or develop any definite style of
building best suited for us. We have no characteristic
national style of architecture, and to that extent are
even below the birds, who have each their characteristic
form of nest, exactly adapted to their wants and habits.

Birds do Alter and Improve their Nests when altered
Conditions require it.

The great uniformity in the architecture of each
species of bird which has been supposed to prove a
nest-building instinct, we may, therefore, fairly impute

THE PHILOSOPHY OF BIRDS' NESTS. 227

to the uniformity of the conditions under which each
species lives. Their range is often very limited, and
they very seldom permanently change their country,
so as to be placed in new conditions. When, how-
ever, new conditions do occur, they take advantage
of them just as freely and wisely as man could do.
The chimney and house-swallows are a standing proof
of a change of habit since chimneys and houses were
built, and in America this change has taken place
within about three hundred years. Thread and worsted
are now used in many nests instead of wool and
horsehair, and the jackdaw shows an affection for the
church steeple which can hardly be explained by in-
stinct. In the more thickly populated parts of the
United States, the Baltimore oriole uses all sorts of
pieces of string, skeins of silk, or the gardener's bass,
to weave into its fine pensile nest, instead of the single
hairs and vegetable fibres it has painfully to seek in
wilder regions ; and Wilson, a most careful observer,
believes that it improves in nest-building by practice
— the older birds making the best nests. The purple
martin takes possession of empty gourds or small boxes,
stuck up for its reception in almost every village and
farm in America ; and several of the American wrens
will also build in cigar boxes, with a small hole cut in
them, if placed in a suitable situation. The orchard
oriole of the United States offers us an excellent ex-
ample of a bird which modifies its nest according to
circumstances. When it is built among firm and stiff

O

branches it is very shallow, but when, as is often the

Q2

228 THE PHILOSOPHY OF BIRDS' NESTS.

case, it is suspended from the slender twigs of the
weeping willow, it is made much deeper, so that when
swayed about violently by the wind the young may not
tumble out. It has been observed also, that the nests
built in the warm Southern States are much slighter
and more porous in texture than those in the colder
regions of the north. Our own house-sparrow equally
well adapts himself to circumstances. When he builds
in trees, as he, no doubt, always did originally, he
constructs a well-made domed nest, perfectly fitted to
protect his young ones ; but when he can find a con-
renient 5liole in a building or among thatch, or in any
well-sheltered place, he takes much less trouble, and
forms a very loosely-built nest.

A curious example of a recent change of habits has
occurred in Jamaica. Previous to 1 854, the palm swift
(Tachornis phsenicobea) inhabited exclusively the palm
trees in a few districts in the island. A colony then
established themselves in two cocoa-nut palms in
Spanish Town, and remained there till 1857, when
one tree was blown down, and the other stripped of
its foliage. Instead of now seeking out other palm
trees, the swifts drove out the swallows who built in
the Piazza of the House of Assembly, and took pos-
session of it, building their nests on the tops of the
end walls and at the angles formed by the beams and
joists, a place which they continue to occupy in con-
siderable numbers. It is remarked that here they form
their nest with much less elaboration than when built
in the palms, probably from being less exposed.

THE PHILOSOPHY OF BIRDS' XE87S. 229

Our little gold-crested warbler also varies its nest
according to circumstances, building an open cup-
shaped nest where there is a natural canopy of thick
foliage, while in more exposed situations it forms a
perfect domed nest with a side entrance. Again, there
are decided imperfections in the nesting of many birds
which are quite compatible with our present theory, but
are hardly so with that of instinct, which is supposed
to be infallible. The Passenger pigeon of America
often crowds the branches with its nests till they break,
and the ground is strewn with shattered nests, eggs,
and young birds. Rooks' nests are often so imperfect
that during high winds the eggs fall out; but the
Window- Swallow is the most unfortunate in this re-
spect, for White, of Selborne, informs us that he has
seen them build, year after year, in places where their
nests are liable to be washed away by a heavy rain and
their young ones destroyed.

Conclusion.

A fair consideration of all these facts will, I think,
fully support the statement with which I commenced,
and show, that the mental faculties exhibited by birds in
the construction of their nests, are the same in kind as
those manifested by mankind in the formation of their
dwellings. These are, essentially, imitation, and a slow
and partial adaptation to new conditions. To compare
the work of birds with the highest manifestations of
human art and science, is totally beside the question. I
do not maintain that birds are gifted with reasoning

230 THE PHILOSOPHY OF BIRDS' NESTS.

faculties at all approaching in variety and extent to
those of man. I simply hold that the phenomena
presented by their mode of building their nests, when
fairly compared with those exhibited by the great mass
of mankind in building their houses, indicate no essen-
tial difference in the kind or nature of the mental facul-
ties employed. If instinct means anything, it means
the capacity to perform some complex act without
teaching or experience. It implies innate ideas of a
very definite kind, and, if established, would overthrow
Mr. Mill's sensationalism and all the modern philosophy
of experience. That the existence of true instinct may
be established in other cases is not impossible, but in
the particular instance of birds' nests, which is usually
considered one of its strongholds, I cannot find a par-
ticle of evidence to show the existence of anything
beyond those lower reasoning and imitative powers,
•which animals are universally admitted to possess.

231

VII.

A THEORY OF BIRDS' NESTS ;
SHOWING THE RELATION OF CERTAIN DIFFERENCES OF
COLOUR IN FEMALE BIRDS, TO THEIR MODE OF

NlDIFICATION.

THE habit of forming a more or less elaborate struc-
ture for the reception of their eggs and young, must
undoubtedly be looked upon as one of the most re-
markable and interesting characteristics of the class of
birds. In other classes of vertebrate animals, such
structures are few and exceptional, and never attain
to the same degree of completeness and beauty. Birds'
nests have, accordingly, attracted much attention, and
have furnished one of the stock arguments to prove
the existence of a blind but unerring instinct in the
lower animals. The very general belief that every
bird is enabled to build its nest, not by the ordinary
faculties of observation, memory, and imitation, but
by means of some innate and mysterious impulse, has
had the bad effect of withdrawing attention from the
very evident relation that exists between the struc-
ture, habits, and intelligence of birds, and the kind of
nests they construct.

In the preceding essay I have detailed several of
these relations, and they teach us, that a consideration
of the structure, the food, and other specialities of a

232 A THEORY OF BINDS' NESIS.

bird's existence, will give a clue, and sometimes a very
complete one, to the reason why it builds its nest of
certain materials, in a definite situation, and in a more
or less elaborate manner.

I now propose to consider the question from a more
general point of view, and to discuss its application
to some important problems in the natural history of
birds.

Changed Conditions and persistent Habits as influencing
Nidification.

Besides the causes above alluded to, there are two
other factors whose effect in any particular case we can
only vaguely guess at, but which must have had an
important influence in determining the existing details
of nidification. These are — changed conditions of ex-

O

istence, whether internal or external, and the influence
of hereditary or imitative habit ; the first inducing al-
terations in accordance with changes of organic struc-
ture, of climate, or of the surrounding fauna and
flora ; the other preserving the peculiarities so pro-
duced, even when changed conditions render them no
longer necessary. Many facts have been already given
which show that birds do adapt their nests to the situa-
tions in which they place them, and the adoption of
eaves, chimneys, and boxes, by swallows, wrens, and
many other birds, shows that they are always ready
to take advantage of changed conditions. It is pro-
bable, therefore, that a permanent change of climate
would cause many birds to modify the form or

A THEORY OF BIRDS' NESTS. 233

materials of their abodes, so as better to protect their
young. The introduction of new enemies to eggs or
young birds, might introduce many alterations tend-
ing to their better concealment. A change in the
vegetation of a country, would often necessitate the
use of new materials. So, also, we may be sure, that
as a species slowly became modified in any external or
internal characters, it would necessarily change in some
degree its mode of building. This effect would be
produced by modifications of the most varied nature ;
such as the power and rapidity of flight, which must
often determine the distance to which a bird will go to
obtain materials for its nest; the capacity of sustain-
ing itself almost motionless in the air, which must
sometimes determine the position in which a nest can
be built ; the strength and grasping power of the foot
in relation to the weight of the bird, a power abso-
lutely essential to the constructor of a delicately- woven
and well-finished nest ; the length and fineness of the
beak, which has to be used like a needle in building
the best textile nests ; the length and mobility of the
neck, which is needful for the same purpose ; the pos-
session of a salivary secretion like that used in the
nests of many of the swifts and swallows, as well as
that of the song-thrush — peculiarities of habits, which
ultimately depend on structure, and which often deter-
mine the material most frequently met with or most
easily to be obtained. Modifications in any of these
characters would necessarily lead, either to a change in
the materials of the nest, or in the mode of combin-

234 A THEORY OF BIRDS' NESTS.

ing them in the finished structure, or in the form or
position of that structure.

During all these changes, however, certain speciali-
ties of nest-building would continue, for a shorter or
a longer time after the causes which had necessitated
them had passed away. Such records of a vanished
past meet us everywhere, even in man's works, not-
withstanding his boasted reason. Not only are the
main features of Greek architecture, mere reproduc-
tions in stone of what were originally parts of a
wooden building, but our modern copyists of Gothic
architecture often build solid buttresses capped with
weighty pinnacles, to support a wooden roof which has
no outward thrust to render them necessary ; and even
think they ornament their buildings by adding sham
spouts of carved stone, while modern waterpipes, stuck
on without any attempt at harmony, do the real duty.
So, when railways superseded coaches, it was thought
necessary to build the first-class carriages to imitate
a number of coach-bodies joined together ; and the
arm-loops for each passenger to hold on by, which
were useful when bad roads made every journey a suc-
cession of jolts and lurches, were continued on our
smooth macadamised mail-routes, and, still more ab-
surdly, remain to this day in our railway carriages,
the relic of a kind of locomotion we can now hardly
realize. Another good example is to be seen in our
boots. When elastic sides came into fashion we had
been so long used to fasten them with buttons or laces,
that a boot without either looked bare and unfinished,

A TIIEOBY OF BIEDS' NESTS. 235

and accordingly the makers often put on a row of
useless buttons or imitation laces, because habit ren-
dered the appearance of them necessary to us. It is
universally admitted that the habits of children and of
savages give us the best clue to the habits and mode
of thought of animals ; and every one must have
observed how children at first imitate the actions of
their elders, without any regard to the use or appli-
cability of the particular acts. So, in savages, many
customs peculiar to each tribe are handed down from
father to son merely by the force of habit, and are
continued long after the purpose which they origi-
nally served has ceased to exist. With these and a
hundred similar facts everywhere around us, we may
fairly impute much of what we cannot understand in
the details of Bird-Architecture to an analogous cause.
If we do not do so, we must assume, either that birds
are guided in every action by pure reason to a far
greater extent than men are, or that an infallible in-
stinct leads them to the same result by a different
road. The first theory has never, that I am aware
of, been maintained by any author, and I have already
shown that the second, although constantly assumed,
has never been proved, and that a large body of facts
is entirely opposed to it. One of my critics has, in-
deed, maintained that I admit " instinct " under the
term a hereditary habit ;" but the whole course of my
argument shows that I do not do so. Hereditary
habit is, indeed, the same as instinct when the term
is applied to some simple action dependent upon a

236 A THEORY OF BIEDS' NESTS.

peculiarity of structure which is hereditary; as when
the descendants of tumbler pigeons tumble, and the
descendants of pouter pigeons pout. In the present
case, however, I compare it strictly to the hereditary,
or more properly, persistent or imitative, habits of
savages, in building their houses as their fathers did.
Imitation is a lower faculty than invention. Children
and savages imitate before they originate ; birds, as
well as all other animals, do the same.

The preceding observations are intended to show,
that the exact mode of nidification of each species of
bird is probably the result of a variety of causes, which
have been continually inducing changes in accordance
with changed organic or physical conditions. The
most important of these causes seem to be, in the first
place, the structure of the species, and, in the second,
its environment or conditions of existence. Now we
know, that every one of the characters or conditions
included under these two heads is variable. We have
seen that, on the large scale, the main features of the
nest built by each group of birds, bears a relation to
the organic structure of that group, and we have,
therefore, a right to infer, that as structure varies, the
nest will vary also in some particular corresponding
to the changes of structure. We have seen also, that
birds change the position, the form, and the con-
struction of their nest, whenever the available ma-
terials or the available situations, vary naturally or
have been altered by man; and we have, therefore,
a right to infer that similar changes have taken place,

A THEORY OF BIBDS' NESTS. 237

when, by a natural process, external conditions have
become in any way permanently altered. AVe must
remember, however, that all these factors are very
stable during many generations, and only change at
a rate commensurate with those of the great physical
features of the earth as revealed to us by geology ; and
we may, therefore, infer that the form and construction
of nests, which we have shown to be dependent on
them, are equally stable. If, therefore, we find less
important and more easily modified characters than
these, so correlated with peculiarities of nidification as
to indicate that one is probably the cause of the
other, we shall be justified in concluding that these
variable characters are dependent on the mode of nidi-
fication, and not that the form of the nest has been
determined by these variable characters. Such a corre-
lation I am now about to point out.

Classification of Nests.

For the purpose of this inquiry it is necessary to
group nests into two great classes, without any re-
gard to their most obvious differences or resemblances,
but solely looking to the fact of whether the contents
(eggs, young, or sitting bird) are hidden or exposed
to view. In the first class we place all those in
which the eggs and young are completely hidden, no
matter whether this is effected by an elaborate covered
structure, or by depositing the eggs in some hollow
tree or burrow underground. In the second, we group
all in which the eggs, young, and sitting bird are

238 A THEORY OF BIRDS' NESTS.

exposed to view, no matter whether there is the most
beautifully formed nest, or none at all. Kingfishers,
which build almost invariably in holes in banks ;
Woodpeckers and Parrots, which build in hollow trees ;
the Icteridaa of America, which all make beautiful
covered and suspended nests ; and our own Wren,
which builds a domed nest, are examples of the former ;
while our Thrushes, Warblers, and Finches, as well
as the Crowshrikes, Chatterers, and Tanagers of the
tropics, together with all Raptorial birds and Pigeons,
and a vast number of others in every part of the
world, all adopt the latter mode of building.

It will be seen that this division of birds according to
their nidification, bears little relation to the character
of the nest itself. It is a functional not a structural
classification. The most rude and the most perfect
specimens of bird-architecture are to be found in both
sections. It has, however, a certain relation to natural
affinities, for large groups of birds, undoubtedly allied,
fall into one or the other division exclusively. The
species of a genus or of a family are rarely divided
between the two primary classes, although they are
frequently divided between the two very distinct modes
of nidification that exist in the first of them.

All the Scansorial or climbing, and most of the
Eissirostral or wide-gaped birds, for example, build
concealed nests; and, in the latter group, the two
families which build open nests, the Swifts and the
Goat-suckers, are undoubtedly very widely separated
from the other families with which they are asso-

A THEORY OF BIRDS' NESTS. 239

ciatecl in our classifications. The Tits vary much in
their mode of nesting, some making open nests con-
cealed in a hole, while others build domed or even pen-
dulous covered nests, but they all come under the same
class. Starlings vary in a similar way. The talking
Mynahs, like our own starlings, build in holes, the
glossy starlings of the East (of the genus Calornis) form
a hanging covered nest, while the genus Sturnopastor
builds in a hollow tree. One of the most striking cases
in which one family of birds is divided between the
two classes, is that of the Finches ; for while most of
the European species build exposed nests, many of
the Australian finches make them dome-shaped,

Sexual differences of Colour in Birds.

Turning now from the nests to the creatures who
make them, let us consider birds themselves from a
somewhat unusual point of view, and form them into
separate groups, according as both sexes, or the males
only, are adorned with conspicuous colours.

The sexual differences of colour and plumage in
birds are very remarkable, and have attracted much
attention; and, in the case of polygamous birds, have
been well explained by Mr. Darwin's principle of sexual
selection. We can, to a great extent, understand
how male Pheasants and Grouse have acquired their
more brilliant plumage and greater size, by the con-
tinual rivalry of the males both in strength and beauty ;
but this theory does not throw any light on the causes
which have made the female Toucan, Bee-eater, Parro-

240 A THEORY OF BIRDS' NESTS.

quet, Macaw and Tit, in almost every case as gay and
brilliant as the male, while the gorgeous Chatterers,
Manakins, Tanagers, and Birds of Paradise, as well as
our own Blackbird, have mates so dull and incon-
spicuous that they can hardly be recognised as be-
longing to the same species.

The Law which connects the Colours of Female Birds
with the mode of Nidification.

The above-stated anomaly can, however, now be ex-
plained by the influence of the mode of nidification,
since I find that, with but very few exceptions, it is
the rule — that when both sexes are of strikingly gay and
conspicuous colours, the nest is of the first class, or
such as to conceal the sitting bird ; while, whenever there
is a striking contrast of colours, the male being gay and
conspicuous, the female dull and obscure, the nest is open
and the sitting bird exposed to view. I will now pro-
ceed to indicate the chief facts that support this state-
ment, and will afterwards explain the manner in which
I conceive the relation has been brought about.

We will first consider those groups of birds in which
the female is gaily or at least conspicuously coloured,
and is in most cases exactly like the male.

1. Kingfishers (Alcedinidse). In some of the most
brilliant species of this family the female exactly re-
sembles the male ; in others there is a sexual difference,
but it rarely tends to make the female less conspicuous.
In some, the female has a band across the breast, which
is wanting in the male, as in the beautiful Halcyon

A THEORY OF BIED& NESTS. 241

diops of Tern ate. In others the band is rufous in the
female, as in several of the American species ; while
in Dacelo gaudichaudii, and others of the same genus,
the tail of the female is rufous, while that of the male
is blue. In most kingfishers the nest is in a deep
hole in the ground ; in Tanysiptera it is said to be
in a hole in the nests of termites, or sometimes in
crevices under overhanging rocks.

2. Motmots (Momotidae). In these showy birds the
sexes are exactly alike, and the nest in a hole under
ground.

3. Puff-birds (Bucconidae). These birds are often
gaily coloured ; some have coral-red bills ; the sexes
are exactly alike, and the nest is in a hole in slop-
ing ground.

4. Trogons (Trogonidsa). In these magnificent birds
the females are generally less brightly coloured than the
males, but are yet often gay and conspicuous. The
nest is in a hole of a tree.

5. Hoopoes (Upupidse). The barred plumage and
long crests of these birds render them conspicuous. The
sexes are exactly alike, and the nest is in a hollow tree.

6. Hornbills (BucerotidaB). These large birds have
enormous coloured bills, which are generally quite as
well coloured and conspicuous in the females. Their
nests are always in hollow trees, where the female is
entirely concealed.

7. Barbets (Capitonidae). These birds are all very
gaily-coloured, and, what is remarkable, the most bril-
liant patches of colour are disposed about the head and

242 A THEORY OF BIED& NESTS.

neck, and are very conspicuous. The sexes are exactly
alike, and the nest is in a hole of a tree.

8. Toucans (Rhamphastidcc). These fine birds are
coloured in the most conspicuous parts of their body,
especially on the large bill, and on the upper and lower
tail coverts, which are crimson, white, or yellow. The
sexes are exactly alike, and they always build in a hol-
low tree.

9. Plaintain-eaters (Musophagidas). Here again the
head and bill are most brilliantly coloured in both sexes,
and the nest is in a hole of a tree.

10. Ground cuckoos (Centropus). These birds are
often of conspicuous colours, and are alike in both sexes.
They build a domed nest.

11. "Woodpeckers (Picidaa). In this family the fe-
males often differ from the males, in having a yellow
or white, instead of a crimson crest, but are almost as
conspicuous. They all nest in holes in trees.

12. Parrots (Psittaci). In this great tribe, adorned
with the most brilliant and varied colours, the rule is,
that the sexes are precisely alike, and this is the case
in the most gorgeous families, the lories, the cockatoos,
and the macaws ; but in some there is a sexual dif-
ference of colour to a slight extent. All build in holes,
mostly in trees, but sometimes in the ground, or in
white ants' nests. In the single case in which the nest
is exposed, that of the Australian ground parrot, Pezo-
porus formosus, the bird has lost the gay colouring of
its allies, and is clothed in sombre and completely pro-
tective tints of dusky green and black.

A THEORY OF EIRDS' NESTS. 243

13. Gapers (EuryljemidaB). In these beautiful East-
ern birds, somewhat allied to the American chatterers,
the sexes are exactly alike, and are adorned with the
most gay and conspicuous markings. The nest is a
woven structure, covered over, and suspended from the
extremities of branches over water.

14. Pardalotus (Ampelida?). In these Australian
birds the females differ from the males, but are
often very conspicuous, having brightly-spotted heads.
Their nests are sometimes dome-shaped, sometimes
in holes of trees, or in burrows in the ground.

15. Tits (Paridae). These little birds are always
pretty, and many (especially among the Indian species)
are very conspicuous. They always have the sexes
alike, a circumstance very unusual among the smaller
gaily-coloured birds of our own country. The nest is
always covered over or concealed in a hole.

16. Nuthatches (Sitta). Often very pretty birds, the
sexes alike, and the nest in a hole.

17. (Sittella). The female of these Australian

nuthatches is often the most conspicuous, being white-
and black-marked. The nest is, according to Gould,
c c completely concealed among upright twigs connected
together."

18. Creepers (Climacteris). In these Australian
creepers the sexes are alike, or the female most con-
spicuous, and the nest is in a hole of a tree.

19. Estrelda, Amadina. In these genera of Eastern
and Australian finches the females, although more or less
different from the males, are still very conspicuous

R 2

214 A THEOBY OF BIRDS' NESTS.

having a red rump, or being white spotted. They
differ from most others of the family in building
domed nests.

20. Certhiola. In these pretty little American
creepers the sexes are alike, and they build a domed
nest.

21. Mynahs (Sturnidas). These showy Eastern star-
lings have the sexes exactly alike. They build in holes
of trees.

22. Calornis (Sturnidce). These brilliant metallic
starlings have no sexual differences. They build a
pensile covered nest.

23. Hangnests (Icteridse). The red or yellow and
black plumage of most of these birds is very conspi-
cuous, and is exactly alike in both sexes. They are
celebrated for their fine purse-shaped pensile nests.

It will be seen that this list comprehends six im-
portant families of Fissirostres, four of Scansores, the
Psittaci, and several genera, with three entire families
of Passeres, comprising about twelve hundred species,
or about one-seventh of all known birds.

The cases in which, whenever the male is gaily
coloured, the female is much less gay or quite incon-
spicuous, are exceedingly numerous, comprising, in
fact, almost all the bright-coloured Passeres, except
those enumerated in the preceding class. The follow-
ing are the most remarkable : —

1. Chatterers (Cotingida3). These comprise some of
the most gorgeous birds in the world, vivid blues,

A 'THEORY OF BIEDS' NESTS. 245

rich purples, and bright reds, being the most charac-
teristic colours. The females are always obscurely
tinted, and are often of a greenish hue, not easily
visible among the foliage.

2. Manakins (Pipridce). These elegant birds, whose
caps or crests are of the most brilliant colours, are
usually of a sombre green in the female sex.

3. Tanagers (Tanagrid^e). These rival the chatterers
in the brilliancy of their colours, and are even more
varied. The females are generally of plain and sombre
hues, and always less conspicuous than the males.

In the extensive families of the warblers (SylviadaB),
thrushes (Turdidaa), flycatchers (Muscicapidas), and
shrikes (Laniadaj), a considerable proportion of the
species are beautifully marked with gay and conspi-
cuous tints, as is also the case in the Pheasants and
Grouse ; but in every case the females are less ga}^
and are most frequently of the very plainest and least
conspicuous hues. Now, throughout the whole of these
families the nest is open, and I am not aware of a
single instance in which any one of these birds builds
a domed nest, or places it in a hole of a tree, or under-
ground, or in any place where it is effectually con-
cealed. *

In considering the question we are now investigating,
it is not necessary to take into account the larger and
more powerful birds, because these seldom depend
much on concealment to secure their safety. In the
raptorial birds bright colours are as a rule absent ;
and their structure and habits are such as not to re-

246 A THEORY OF BIRDS' NESTS.

quire any special protection for the female. The larger
waders are sometimes very brightly coloured in both
sexes ; but they are probably little subject to the attacks
of enemies, since the scarlet ibis, the most conspicuous
of birds, exists in immense quantities in South America.
In game birds and water-fowl, however, the females
are often very plainly coloured, when the males are
adorned with brilliant hues ; and the abnormal family
of the Megapodida; offers us the interesting fact of an
identity in the colours of the sexes (which in Mega-
cephalon and Talegalla are somewhat conspicuous), in
conjunction with the habit of not sitting on the eggs
at all.

What the Facts Teach us.

Taking the whole body of evidence here brought
forward, embracing as it does almost every group of
bright-coloured birds, it will, I think, be admitted
that the relation between the two series of facts in
the colouring and nidification of birds has been suffi-
ciently established. There are, it is true, a few
apparent and some real exceptions, which I shall con-
sider presently ; but they are too few and unimportant
to weigh much against the mass of evidence on the
other side, and may for the present be neglected.
Let us then consider what we are to do with this
unexpected set of correspondences between groups of
phenomena which, at first sight, appear so discon-
nected. Do they fall in with any other groups of
natural phenomena ? Do they teach us anything of the

A THEORY OF BIRDS1 NESTS. 247

way in which nature works, and give us any insight
into the causes which have brought about the marvel-
lous variety, and beauty, and harmony of living things?
I believe we can answer these questions in the affirm-
ative; and I may mention, as a sufficient proof that
these are not isolated facts, that I was first led to
see their relation to each other by the study of an
analogous though distinct set of phenomena among in-
sects, that of protective resemblance and " mimicry."
On considering this remarkable series of correspond-
ing facts, the first thing we are taught by them seems
to be, that there is no incapacity in the female sex
among birds, to receive the same bright hues and
strongly contrasted tints with which their partners are
so often decorated, since whenever they are protected
and concealed during the period of incubation they
are similarly adorned. The fair inference is, that it is
chiefly due to the absence of protection or concealment
during this important epoch, that gay and conspicuous
tints are withheld or left undeveloped. The mode in
which this has been effected is very intelligible, if we
admit the action of natural and sexual selection. It
would appear from the numerous cases in which both
sexes are adorned with equally brilliant colours (while
both saxes are rarely armed with equally developed
offensive and defensive weapons when not required for
individual safety), that the normal action of " sexual
selection " is to develop colour and beauty in both
sexes, by the preservation and multiplication of all
varieties of colour in either sex which are pleasing

248 A THEOEY OF STUDS' NESTS.

to the other. Several very close observers of the
habits of animals have assured me, that male birds and
quadrupeds do often take very strong likes and dis-
likes to individual females, and we can hardly believe
that the one sex (the female) can have a general taste
for colour while the other has no such taste. How-
• ever this may be, the fact remains, that in a vast
number of cases the female acquires as brilliant and
as varied colours as the male, and therefore most pro-
bably acquires them in the same way as the male does ;
that is, either because the colour is useful to it, or is
correlated with some useful variation, or is pleasing to
the other sex. The only remaining supposition is that
it is transmitted from the other sex, without being ot
any use. From the number of examples above adduced
of bright colours in the female, this would imply that
colour-characters acquired by one sex are generally
(but not necessarily) transmitted to the other. If this
be the case it will, I think, enable us to explain the
phenomena, even if we do not admit that the male
bird is ever influenced in the choice of a mate by her
more gay or perfect plumage.

The female bird, while sitting on her eggs in an
uncovered nest, is much exposed to the attacks of
enemies, and any modification of colour which ren-
dered her more conspicuous would often lead to her
destruction and that of her offspring. All variations
of colour in this direction in the female, would there-
fore sooner or later be eliminated, while such modifi-
cations as rendered her inconspicuous, by assimilating

A THEORY OF BIRDS' NESTS. 210

her to surrounding objects, as the earth or the foliage,
would, on the whole, survive the longest, and thus
lead to the attainment of those brown or green and
inconspicuous tints, which form the colouring (of the
upper surface at least), of the vast majority of female
birds which sit upon open nests.

This does not imply, as some have thought, that all
female birds were once as brilliant as the males. The
change has been a very gradual one, generally dating
from the origin of genera or of larger groups, but
there can be no doubt that the remote ancestry of
birds having great sexual differences of colour, were
nearly or quite alike, sometimes (perhaps in most
cases) more nearly resembling the female, but occa-
sionally perhaps being nearer what the male is now.
The young birds (which usually resemble the females)
will probably give some idea of this ancestral type,
and it is well known that the young of allied species
and of different sexes are often undistinguishable.

Colour more variable than Structure or Habits, and
therefore the Character which has generally been
Modified.

At the commencement of this essay, I have endea-
voured to prove, that the characteristic differences and
the essential features of birds' nests, are dependent on
the structure of the species and upon the present and
past conditions of their existence. Both these factors
are more important and less variable than colour; and
we must therefore conclude that in most cases the mode

250 A THEORY OF BIRDS' NESTS.

of nidification (dependent on structure and environ-
ment) lias been the cause, and not the effect, of the
similarity or differences of the sexes as regards colour.
When the confirmed habit of a group of birds, was to
build their nests in holes of trees like the toucans, or in
holes in the ground like the kingfishers, the protection
the female thus obtained, during the important and
dangerous time of incubation, placed the two sexes on
an equality as regards exposure to attack, and allowed
" sexual selection," or any other cause, to act unchecked
in the development of gay colours and conspicuous
markings in both sexes.

When, on the other hand (as in the Tanagers and
Flycatchers), the habit of the whole group was to build
open cup-shaped nests in more or less exposed situa-
tions, the production of colour and marking in the
female, by whatever cause, was continually checked by
its rendering her too conspicuous, while in the male it
had free play, and developed in him the most gorgeous
hues. This, however, was not perhaps universally the
case ; for where there was more than usual intelligence
and capacity for change of habits, the danger the fe-
male was exposed to by a partial brightness of colour
or marking might lead to the construction of a concealed
or covered nest, as in the case of the Tits and Hang-
nests. When this occurred, a special protection to the
female would be no longer necessary ; so that the
acquisition of colour and the modification of the nest,
might in some cases act and react on each other and
attain their full development together.

A THEORY OF ZIBDS' NESTS. 251

Exceptional Cases confirmatory of the above
Explanation.

There exist a few very curious and anomalous facts
in the natural history of birds, which fortunately serve
as crucial tests of the truth of this mode of explaining
the inequalities of sexual colouration. It has been long
known, that in some species the males either assisted in,
or wholly performed, the act of incubation. It has also
been often noticed, that in certain birds the usual sexual
differences were reversed, the male being the more
plainly coloured, the female more gay and often larger.
I am not, however, aware that these two anomalies had
ever been supposed to stand to each other in the rela-
tion of cause and effect, till I adduced them in support
of my views of the general theory of protective adapta-
tion. Yet it is undoubtedly the fact, that in the best
known cases in which the female bird is more conspi-
cuously coloured than the male, it is either positively
ascertained that the latter performs the duties of in-
cubation, or there are good reasons for believing such
to be the case. The most satisfactory example is that
of the Gray Phalarope (Phalaropus fulicarius), the
sexes of which are alike in winter, while in summer
the female instead of the male takes on a gay and
conspicuous nuptial plumage ; but the male performs
the duties of incubation, sitting upon the eggs, which
are laid upon the bare ground.

In the Dotterell (Eudromias morinellus) the female
is larger and more brightly coloured than the male ; and

252 , A THEORY OF BIBBS' NESTS.

here, also, it is almost certain that the latter sits upon
the eggs. The Turnices of India also, have the female
larger and often more brightly coloured ; and Mr.
Jerdon states, in his " Birds of India," that the natives
report, that, during the breeding season, the females
desert their eggs and associate in flocks, while the
males are employed in hatching the eggs. In the few
other cases in which the females are more brightly
coloured, the habits are not accurately known. The
case of the Ostriches and Emeus will occur to many as
a difficulty, for here the male incubates, but is not less
conspicuous than the female ; but there are two reasons
why the case does not apply ; — the birds are too large
to derive any safety from concealment, from enemies
which would devour the eggs they can defend them-
selves by force, while to escape from their personal foes
they trust to speed.

We find, therefore, that a very large mass of facts
relating to the sexual colouration and the mode of
nidification of birds, including some of the most
extraordinary anomalies to be found in their natural
history, can be shown to have an interdependent re-
lation to each other, on the simple principle of the need
of greater protection to that parent which performs the
duties of incubation. Considering the very imperfect
knowledge we possess of the .habits of most extra-
European birds, the exceptions to the prevalent rule
are few, and generally occur in isolated species or in
small groups ; while several apparent exceptions can
be shown to be really confirmations of the law.

A THEORY OF BIBBS' NESTS. 253

Real or apparent Exceptions to the Law stated at
page 240.

The only marked exceptions I have been able to
discover are the following : —

1. King crows (Dicrourus). These birds are of a
glossy black colour with long forked tails. The sexes
present no difference, and they build open nests. This
apparent exception may probably be accounted for by
the fact that these birds do not need the protection
of a less conspicuous colour. They are very pugna-
cious, and often attack and drive away crows, hawks,
and kites ; and as they are semi-gregarious in their
habits, the females are not likely to be attacked while
incubating.

2. Orioles (Qriolidae). The true orioles are very gay
birds ; the sexes are, in many Eastern species, either
nearly or quite alike, and the nests are open. This
is one of the most serious exceptions, but it is one
that to some extent proves the rule ; for in this case
it has been noticed, that the parent birds display
excessive care and solicitude in concealing the nest
among thick foliage, and in protecting their offspring
by incessant and anxious watching. This indicates
that the want of protection consequent on the bright
colour of the female makes itself felt, and is obviated
by an increased development of the mental faculties.

3. Ground thrushes (Pittidoo). These elegant and
brilliantly-coloured birds are generally alike in both
sexes, and build an open 'nest. It is curious, however,

254 A THEORY OF BIRDS' 2fESTSf

that this is only an apparent exception, for almost all
the bright colours are on the under surface, the back
being usually olive green or brown, and the head black,
with brown or whitish stripes, all which colours would
harmonize with the foliage, sticks, and roots which
surround the nest, built on or near the ground, and
thus serve as a protection to the female bird.

4. Grallina Australis. This Australian bird is of
strongly contrasted black and white colours. The sexes
are exactly alike, and it builds an open clay nest in
an exposed situation on a tree. This appears to be
a most striking exception, but I am by no means
sure that it is so. We require to know what tree it
usually builds on, the colour of the bark or of the
lichens that grow upon it, the tints of the ground,
or of other surrounding objects, before we can say
that the bird, when sitting on its nest, is really con-
spicuous. It has been remarked that small patches
of wrhite and black blend at a short distance to form
grey, one of the commonest tints of natural objects.

5. Sunbirds (Nectarineidse). In these beautiful
little birds the males only are adorned with brilliant
colours, the females being quite plain, yet they build
covered nests in all the cases in which the nidification
is known. This is a negative rather than a positive
exception to the rule, since there may be other causes
besides the need for protection, which prevent the
female acquiring the gay colours of her mate, and
there is one curious circumstance which tends to
elucidate it The male of Leptocoma zeylanica is said

A THEORY OF BIRDS' NESTS. 255

to assist in incubation. It is possible, therefore, that
the group may originally have used open nests, and
some change of conditions, leading the male bird to
sit, may have been followed by the adoption of a
domed nest. This is, however, the most serious ex-
ception I have yet found to the general rule.

6. Superb warblers (MaluridaB). The males of these
little birds are adorned with the most gorgeous colours,
while the females are very plain, yet they make domed
nests. It is to be observed, however, that the male
plumage is nuptial merely, and is retained for a very
short time ; the rest of the year both sexes are plain
alike. It is probable, therefore, that the domed nest
is for the protection of these delicate little birds against
the rain, and that there is some unknown cause which
has led to the development of colour in the males only.

There is one otlier case which at first sight looks
like an exception, but which is far from being one
in reality, and deserves to be mentioned. In the
beautiful Waxwing, (Bombycilla garrula,) the sexes
are very nearly alike, and the elegant red wax tips to
the wing-feathers are nearly, and sometimes quite,
as conspicuous in the female as in the male. Yet it
builds an open nest, and a person looking at the bird
would say it ought according to my theory to cover
its nest. But it is, in reality, as completely protscted
by its colouration as the most plainly coloured bird
that flies. It breeds only in very high latitudes, and
the nest, placed in fir-trees, is formed chiefly of
lichens. Now the delicate gray and ashy and purplish

256 A THEORY OF BIRDS NESTS.

hues of the head and back, together with the yellow
of the wings and tail, are tints that exactly harmonize
with the colours of various species of lichens, while
the brilliant red wax tips exactly represent the crimson
fructification of tho common lichen, Cladonia cocci-
fera. When sitting on its nest, therefore, the female
bird will exhibit no colours that are not common
to the materials of which it is constructed ; and the
several tints are distributed in about the same pro-
portions as they occur in nature. At a short distance
the bird would be indistinguishable from the nest it is
sitting on, or from a natural clump of lichens, and
will thus be completely protected.

I think I have now noticed all exceptions of any
importance to the law of dependence of sexual colour
on nidification. It will be seen that they are very
few in number, compared with those which support
the generalization ; and in several cases there are
circumstances in the habits or structure of the species
that sufficiently explain them. It is remarkable also
that I have found scarcely any positive exceptions,
that is, cases of very brilliant or conspicuous female
birds in which the nest was not concealed. Much less
can there be shown any group of birds, in which the
females are all of decidedly conspicuous colours on
the upper surface, and yet sit in open nests. The
many cases in which birds of dull colours in both
sexes make domed or concealed nests, do not, of course,
affect this theory one way or the other ; since its
purpose is only to account for the fact, that brilliant

A THEORY OF BIRDS' NESTS. 257

females of brilliant males are always fou'.id to have
covered or hidden nests, while obscure females of
brilliant males almost always have open and exposed
nests. The fact that all classes of nests occur with
dull coloured birds in both sexes merely shows, as I
have strongly maintained, that in most cases the
character of the nest determines the colouration of
the female, and not vice versa.

If the views here advocated are correct, as to the
various influences that have determined the specialities
of every bird's nest, and the general colouration of
female birds, with their action and reaction on each
other, we can hardly expect to find evidence more
complete than that here set forth. Nature is such a
tangled web of complex relations, that a series of
correspondences running through hundreds of species,
genera, and families, in every part of the system, can
hardly fail to indicate a true casual connexion ; and
when, of the two factors in the problem, one can be
shown to be dependent on the most deeply seated and
the most stable facts of structure and conditions of
life, while the other is a character universally admitted
to be superficial and easily modified, there can be
little doubt as to which is cause and which effect.

Various modes of Protection of Animals,

But the explanation of the phenomenon here at-
tempted does not rest alone on the facts I have been
able now to adduce. In the essay on " Mimicry,"
it is shown how important a part the necessity for

258 A THEORY OF BIRDS' NESTS.

protection has played, in determining the external form
and colouration, and sometimes even the internal
structure of animals.

As illustrating this latter point, I may refer to the
remarkable hooked, branched, or star-like spiculaa in
many sponges, which are believed to have the function
chiefly, of rendering them unpalatable to other crea-
tures. The Holothuridaa or sea-cucumbers possess a
similar protection, many of them having anchor-shaped
spicules embedded in their skin, as the Synapta ; while
others (Cuviera squamata) are covered with a hard
calcareous pavement. Many of these are of a bright
red or purple colour, and are very conspicuous, while
the allied Trepangj or Beche-de-mer (Holothuria
edulis), which is not armed with any such defensive
weapons, is of a dull sand- or mud-colour, so as hardly
to be distinguished from the sea bed on which it
reposes. Many of the smaller marine animals are
protected by their almost invisible transparency, while
those that are most brightly coloured will be often
found to have a special protection, either in stinging
tentacles like Physalia, or in a hard calcareous crust,
as in the star fishes.

Females of some Groups require and obtain more Pro-
tection than the Males.

In the struggle for existence incessantly going on,
protection or concealment is one of the most general
and most effectual means of maintaining life ; and it is
by modifications of colour that this protection can be

A THEORY OF BIRDS' NESTS. 259

most readily obtained, since no other character is sub-
ject to such numerous and rapid variations. The case I
have now endeavoured to illustrate is exactly analogous
to what occurs among butterflies. As a general rule,
the female butterfly is of dull and inconspicuous colours,
even when the male is most gorgeously arrayed ; but
when the species is protected from attack by a disa-
greeable odour, as in the Heliconidaa, DanaidaB and
Acrceida?, both sexes display the same or equally bril-
liant hues. Among the species which gain a protec-
tion by imitating these, the very weak and slow-flying
Leptalides resemble them in both sexes, because both
sexes alike require protection, while in the more active
and strong-winged genera — Papilio, Pieris, and Dia-
dema — it is generally the females only that mimic the
protected groups, and in doing so often become actually
more gay and more conspicuous than the males, thus
reversing the usual and in fact almost universal char-
acters of the sexes. So, in the wonderful Eastern leaf-
insects of the genus Phyllium, it is the female only
that so marvellously imitates a green leaf; and in all
these cases the difference can be traced to the greater
need of protection for the female, on whose continued
existence, while depositing her eggs, the safety of the
race depends. In Mammalia and in reptiles, however
brilliant the colours may be, there is rarely any differ-
ence between that of the sexes, because the female is
not necessarily more exposed to attack than the male.
It may, I think, be looked upon as a confirmation of
this view, that no single case is known either in the

s 2

260 A THEORY OF BIRDS' NESTS.

above-named genera — Papilio, Pieris, and Diadema— or
in any other butterfly, of a male alone, mimicking
one of the Danaida3 or Heliconidae. Yet the necessary
colour is far more abundant in the males, and varia-
tions always seem ready for any useful purpose. This
seems to depend on the general law, that each species
and each sex can only be modified just as far as is
absolutely necessary for it to maintain itself in the
struggle for existence, not a step further. A male
insect by its structure and habits is less exposed to
clanger, and also requires less protection than the
female. It cannot, therefore, alone acquire any further
protection through the agency of natural selection.
But the female requires some extra protection, to
balance the greater danger to which she is exposed,
and her greater imroriance to the existence of the
species ; and this she always acquires, in one way or
another, through the action of natural selection.

In his " Origin of Species," fourth edition, p. 241,
Mr. Darwin recognises the necessity for protection as
sometimes being a cause of the obscure colours of fe-
male birds ; but he does not seem to consider it so
very important an agent in modifying colour as I am
disposed to do. In the same paragraph (p. 240), he
alludes to the fact of female birds and butterflies being
sometimes very plain, sometimes as gay as the males;
but, apparently, considers this mainly due to peculiar
laws of inheritance, which sometimes continue acquired
colour in the line of one sex only, sometimes in both.
Without denying the action of such a law (which Mr.

A THEOEY OF ZIBDS' XESTS. 201

Darwin informs me he has facts to support), I impute
the difference, in the great majority of cases, to the
greater or less need of protection in the female sex in
these groups of animals.

Conclusion.

To some persons it will perhaps appear, that the
causes to which I impute so much of the external as-
pect of nature are too simple, too insignificant, and too
unimportant for such a mighty work. But I would
ask them to consider, that the great object of all the
peculiarities of animal structure is to preserve the life
of the individual, and maintain the existence of the
species. Colour has hitherto been too often looked
upon as something adventitious and superficial, some-
thing given to an animal not to be useful to itself, but
solely to gratify man or even superior beings — to add
to the beauty and ideal harmony of nature. If this
were the case, then, it is evident that the colours of
organized beings would be an exception to most other
natural phenomena. They would not be the product
of general laws, or determined by ever-changing ex-
ternal conditions ; and we must give up all inquiry
into their origin and causes, since (by the hypothesis)
they are dependent on a Will whose motives must ever
be unknown to us. But, strange to say, no sooner do
we begin to examine and classify the colours of natural
objects, than we find that they are intimately related
to a variety of other phenomena, and are like them
strictly subordinated to general laws. I have here

262 A THEORY OF BIRDS' NESTS.

attempted to elucidate some of these laws in the case
of birds, and have shown how the mode of nidification
has affected the colouring of the female sex in this
group. I have before shown to how great an extent,
and in how many ways, the need of protection has
determined the colours of insects, and of some groups
of reptiles and mammalia, and I would now call parti-
cular attention to the fact that the gay tints of flowers,
so long supposed to be a convincing proof that colour
has been bestowed for other purposes than the good of
its possessor, have been shown by Mr. Darwin to follow
the same great law of utility. Flowers do not often
need protection, but very often require the aid of insects
to fertilize them, and maintain their reproductive powers
in the greatest vigour. Their gay colours attract in-
sects, as do also their sweet odours and honeyed secre-
tions ; and that this is the main function of colour in
flowers is shown by the striking fact, that those flowers
which can be perfectly fertilized by the wind, and do
not need the aid of insects, rarely or never have gaily-
coloured flowers.

This wide extension of the general principle of utility
to the colours of such varied groups, both in the animal
and vegetable kingdoms, compels us to acknowledge
that the " reign of law" has been fairly traced into this
stronghold of the advocates of special creation. And
to those who oppose the explanation I have given of
the facts adduced in this essay, I would again respect-
fully urge that they must grapple with the whole of the
facts, not one or two of them only. It will be admitted

A THEORY OF BIRDS' NESTS. 2(53

that, on the theory of evolution and natural selection, a
wide range of facts with regard to colour in nature have
been co-ordinated and explained. Until at least an
equally wide range of facts can be shown to be in har-
mony with any other theory, we can hardly be expected
to abandon that which has already done such good ser-
vice, and which has led us to the discovery of so many
interesting and unexpected harmonies among the most
common (but hitherto most neglected and least un-
derstood), of the phenomena presented by organized
beings.

2G4

VIII.
CREATION BY LAW.

AMONG the various criticisms that have appeared on
Mr. Darwin's celebrated " Origin of Species," there
is, perhaps, none that will appeal to so large a number
of well educated and intelligent persons, as that con-
tained in the Duke .of Argyll's " Reign of Law." The
noble author represents the feelings and expresses the
ideas of that large class, who take a keen interest in
the progress of Science in general, and especially that
of Natural History, but have never themselves studied
nature in detail, or acquired that personal knowledge
of the structure of closely allied forms, — the wonder-
ful gradations from species to species and from group
to group, and the infinite variety of the phenomena
of " variation " in organic beings, — which are abso-
lutely necessary for a full appreciation of the facts and
reasonings contained in Mr. Darwin's great work.

Nearly half of the Duke's book is devoted to an
exposition of his idea of " Creation by Law," and he
expresses so clearly what are his difficulties and ob-
jections as regards the theory of u Natural Selection,"
that I think it advisable that they should be fairly
answered, and that his own views should be shown to
lead to conclusions, as hard to accept as any which he
imputes to Mr. Darwin.

CREATION BY LAW. 2C5

The point on which the Duke of Argyll lays most
stress, is, that proofs of Mind everywhere meet us in
Nature, and are more especially manifest wherever we
find "contrivance" or "beauty." He maintains that
this indicates the constant supervision and direct in-
terference of the Creator, and cannot possibly be
explained by the unassisted action of any combination
of laws. Now, Mr. Darwin's work has for its main
object, to show, that all the phenomena of living
things, — all their wonderful organs and complicated
structures, their infinite variety of form, size, and
colour, their intricate and involved relations to each
other, — may have been produced by the action of a
few general laws of the simplest kind, laws which are
in most cases mere statements of admitted facts. The
chief of these laws or facts are the following : —

1. The Law of Multiplication in Geometrical Pro-
gression.— All organized beings have enormous powers
of multiplication. Even man, who increases slower
than all other animals, could under the most favour-
able circumstances double his numbers every fifteen
years, or a hundred-fold in a century. Many animals
and plants could increase their numbers from ten to
a thousand-fold every year.

2. The Law of Limited Populations. — The number
of living individuals of each species in any country,
or in the whole globe, is practically stationary ; whence
it follows that the whole of this enormous increase
must die off almost as fast as produced, except only
those individuals for whom room is made by the death

266 CREATION BY LAW.

of parents. As a simple but striking example, take
an oak forest. Every oak will drop annually thou-
sands or millions of acorns, but till an old tree falls,
not one of these millions can grow up into an oak.
They must die at various stages of growth.

3. The Law of Heredity, or Likeness of Offspring
to their Parents. — This is a universal, but not an
absolute law. All creatures resemble their parents in
a high degree, and in the majority of cases very ac-
curately; so that even individual peculiarities, of what-
ever kind, in the parents, are almost always transmitted
to some of the offspring.

4. The Law of Variation. — This is fully expressed
by the lines : —

" No being on this earthly ball,
Is like another, all in all."

Offspring resemble their parents very much, but not
wholly — each being possesses its individuality. This
u variation " itself varies in amount, but it is always
present, not only in the whole being, but in every
part of every being. Every organ, every character,
every feeling is individual ; that is to say, varies from
the same organ, character, or feeling in every other
individual.

5. The Law of unceasing Change of Physical Con-
ditions upon the Surface of the Earth. — Geology shows
us that this change has always gone on in times past,
and we also know that it is now everywhere going on.

6. The Equilibrium or Harmony of Nature. — When
a species is well adapted to the conditions which

CREATION BY LAW. 267

environ it, it flourishes ; when imperfectly adapted it
decays ; when ill-adapted it becomes extinct. If all
the conditions which determine an organism's well-
being are taken into consideration, this statement can
hardly be disputed.

This series of facts or laws, are mere statements of
what is the condition of nature. They are facts or
inferences which are generally known, generally ad-
mitted— but in discussing the subject of the " Origin
of Species " — as generally forgotten. It is from these
universally admitted facts, that the origin of all the
varied forms of nature may be deduced by a logical
chain of reasoning, which, however, is at every step
verified and shown to be in strict accord with facts ;
and, at the same time, many curious phenomena which
can by no other means be understood, are explained
and accounted for. It is probable, that these primary
facts or laws are but results of the very nature of life,
and of the essential properties of organized and un-
organized matter. Mr. Herbert Spencer, in his " First
Principles" and his " Biology" has, I think, made us
able to understand how this may be; but at present
we may accept these simple laws without going further
back, and the question then is — whether the variety, the
harmony, the contrivance, and the beauty we perceive
in organic beings, can have been produced by the
action of these laws alone, or whether we are required
to believe in the incessant interference and direct action
of the mind and will of the Creator. It is simply a

2G8 CREATION BY LAW.

question of how the Creator has worked. The Duke
(and I quote him as having well expressed the views
of the more intelligent of Mr. Darwin's opponents)
maintains, that He has personally applied general laws
to produce effects, which those laws are not in them-
selves capable of producing; that the universe alone,
with all its laws intact, would be a sort of chaos, with-
out variety, without harmony, without design, without
beauty ; that there is not (and therefore we may pre-
sume that 'there could not be) any self-developing
power in the universe. I believe, on the contrary,
that the universe is so constituted as to be self-regu-
lating; that as long as it contains Life, the forms under
which that life is manifested have an inherent power
of adjustment to each other and to surrounding na-
ture; and that this adjustment necessarily leads to the
greatest amount of variety and beauty and enjoyment,
because it does depend on general laws, and not on
a continual supervision and re-arrangement of details.
As a matter of feeling and religion, I hold this to be
a far higher conception . of the Creator and of the
Universe that that which may be called the u continual
interference " hypothesis ; but it is not a question to
be decided by our feelings or convictions, it is a ques-
tion of facts and of reason. Could the change, which
Geology shows us has ever taken place in the forms
of life, have been produced by general laws, or does
it imperatively require the incessant supervision of a
creative mind ? This is the question for us to consider,
and our opponents have the difficult task of proving

CREATION BY LAW. 269

a negative, if we show that there are both facts and
analogies in our favour.

Mr. Darwin's Metaphors liable to Misconception.

Mr. Darwin has laid himself open to much miscon-
ception, and has given to his opponents a powerful
weapon against himself, by his continual use of meta-
phor in describing the wonderful co-adaptations of
organic beings.

" It is curious," says the Duke of Argyll, " to ob-
serve the language which this most advanced disciple
of pure naturalism instinctively uses, when he has to
describe the complicated structure of this curious
order of plants (the Orchids). f Caution in ascribing
intentions to nature,' does not seem to occur to him as
possible. Intention is the one thing which he does see,
and which, when he does not see, he seeks for diligently
until he finds it. He exhausts every form of words and
of illustration, by which intention or mental purpose
can be described. ' Contrivance ' — c curious contriv-
ance,'— i beautiful contrivance,' — these are expressions
which occur over and over again. Here is one sen-
tence describing the parts of a particular species : ' the
Labellum is developed into a long nectary, in order to
attract Lepidoptera, and we shall presently give reason
for suspecting that the nectar is purposely so lodged,
that it can be sucked only slowly in order to give time
for the curious chemical quality of the viscid matter
setting hard and dry.' ' Many other examples of
similar expressions are quoted by the Duke, who

270 CREATION BY LAW.

maintains that no explanation of these " contrivances "
has been or can be given, except on the supposition of
a personal contriver, specially arranging the details of
each case, although causing them to be produced by
the ordinary processes of growth and reproduction.

Now there is a difficulty in this view of the origin
of the structure of Orchids which the Duke does not
allude to. The majority of flowering plants are fer-
tilized, either without the agency of insects or, when
insects are required, without any very important modi-
fication of the structure of the flower. It is evident,
therefore, that flowers might have been formed as
varied, fantastic, and beautiful as the Orchids, and yet
have been fertilized without more complexity of struc-
ture than is found in Violets, or Clover, or Primroses,
or a thousand other flowers. The strange springs
and traps and pitfalls found in the flowers of Orchids
cannot be necessary per se, since exactly the same end
is gained in ten thousand other flowerg which do not
possess them. Is it not then an extraordinary idea,
to imagine the Creator of the Universe contriving the
various complicated parts of these flowers, as a me-
chanic might contrive an ingenious toy or a difficult
puzzle? Is it not a more worthy conception that they
are some of the results of those general laws which
were so co-ordinated at the first introduction of life
upon the earth as to result necessarily in the utmost
possible development of varied forms ?

But let us take one of the simpler cases adduced
and see if our general laws are unable to account for it.

CREATION BY LAW. 271

A Case of Orchis-structure explained by Natural
Selection.

There is a Madagascar Orchis — the Angnccum ses-
quipeclale — with an immensely long and deep nectary.
How did such an extraordinary organ come to be
developed ? Mr. Darwin's explanation is this. The
pollen of this flower can only be removed by the base
of the proboscis of some very large moths, when trying
to get at the nectar at the bottom of the vessel. The
moths writh the longest probosces would do this most
effectually ; they would be rewarded for their long
tongues by getting the most nectar ; whilst on the other
hand, the flowers with the deepest nectaries would be
the best fertilized by the largest moths preferring
them. Consequently, the deepest nectar ied Orchids
and the longest tongued moths would each confer on the
other an advantage in the battle of life. This would
tend to their respective perpetuation, and to the con-
stant lengthening of nectaries and probosces. Now
let it be remembered, that what we have to account
for, is only the unusual length of this organ. A nec-
tary is found in many orders of plants and is especially
common in the Orchids, but in this one case only is
it more than a foot long. How did this arise ? We
begin with the fact, proved experimentally by Mr.
Darwin, that moths do visit Orchids, do thrust their
spiral trunks into the nectaries, and do fertilize them
by carrying the pollinia of one flower to the stigma of
another. He has further explained the exact mechanism

272 CREATION BY LAW.

by which this is effected, and the Duke of Argyll ad-
mits the accuracy of his observations. In our British
species, such as Orchis pyramidalis, it is not necessary
that there should be any exact adjustment between
the length of the nectary and that of the proboscis of
the insect ; and thus a number of insects of various
sizes are found to carry away the pollinia and aid in
the fertilization. In the Angracum sesquipedale, how-
ever, it is necessary that the proboscis should be forced
into a particular part of the flower, and this would
only be done by a large moth burying its proboscis
to the very base, and straining to drain the nectar
from the bottom of the long tube, in which it occupies
a depth of one or two inches only. Now let us start
from the time when the nectary was only half its
present length or about six inches, and was chiefly
fertilized by a species of moth which appeared at the
time of the plant's flowering, and whose proboscis was
of the same length. Among the millions of flowers
of the Angra3cum produced every year, some would
always be shorter than the average, some longer. The
former, owing to the structure of the flower, would
not get fertilized, because the moths could get all the
nectar without forcing their trunks down to the very
base. The latter would be well fertilized, and the
longest would on the average be the best fertilized of
all. By this process alone the average length of the
nectary would annually increase, because, the short-nec-
taried flowers being sterile and the long ones having
abundant offspring, exactly the same effect would be

CREATION BY LAW. 273

produced as if a gardener destroyed the short ones
and sowed the seed of the long ones only ; and this
we know by experience would produce a regular in-
crease of length, since it is this very process which
has increased the size and changed the form of our
cultivated fruits and flowers.

But this would lead in time to such an increased
length of the nectary that many of the moths could
only just reach the surface of the nectar, and only the
few with exceptionally long trunks be able to suck up a
considerable portion.

This would cause many moths to neglect these flowers
because they could not get a satisfying supply of nec-
tar, and if these were the only moths in the country
the flowers would undoubtedly suifer, and the further
growth of the nectary be checked by exactly the same
process which had led to its increase. But there are
an immense variety of moths, of various lengths of
proboscis, and as the nectary became longer, other and
larger species would become the fertilizers, and would
carry on the process till the largest moths became
the sole agents. Now, if not before, the moth would
also be affected, for those with the longest probosces
would get most food, would be the strongest and most
vigorous, would visit and fertilize the greatest number
of flowers, and would leave the largest number of de-
scendants. The flowers most completely fertilized by
these moths being those which had the longest nec-
taries, there would in each generation be on the average
an increase in the length of the nectaries, and also

T

274 CREATION BY LAW.

an average increase in the length of the probosces of
the moths ; and this would be a necessary result from
the fact that nature ever fluctuates about a mean, or
that in every generation there would be flowers with
longer and shorter nectaries, and moths with longer
and shorter probosces than the average. No doubt
there are a hundred causes that might have checked
this process before it had reached the point of develop-
ment at which we find it. If, for instance, the
variation in the quantity of nectar had been at any
stage greater than the variation in the length of the
nectary, then smaller moths could have reached it
and have effected the fertilization. Or if the growth

o

of the probosces of the moths had from other causes
increased quicker than that of the nectary, or if the
increased length of proboscis had been injurious to
them in any way, or if the species of moth with the
longest proboscis had become much diminished by
some enemy or other unfavourable conditions, then,
in any of these cases, the shorter nectaried flowers,
which would have attracted and could have been ferti-
lized by the smaller kinds of moths, would have had
the advantage. And checks of a similar nature to
these no doubt have acted in other parts of the world,
and have prevented such an extraordinary develop-
ment of nectary as has been produced by favourable
conditions in Madagascar only, and in one single species
of Orchid. I may here mention that some of the
large Sphinx moths of the tropics have probosces
nearly as long as the nectary of AngraBCum sesquipe-

CEEATION Z?F LAW. 275

dale. I have carefully measured the proboscis of a
specimen of Macrosila cluentius from South America, in
the collection of the British Museum, and find it to
be nine inches and a quarter long ! One from tropical
Africa (Macrosila morganii) is seven inches and a
half. A species having a proboscis two or three inches
longer could reach the nectar in the largest flowers
of Angraecum sesquipedale, whose nectaries vary in
length from ten to fourteen inches. That such a moth
exists in Madagascar may be safely predicted ; and
naturalists who visit that island should search for it
with as much confidence as Astronomers searched for
the planet Neptune, — and I venture to predict they
will be equally successful !

Now, instead of this beautiful self-acting adjust-
ment, the opposing theory is, that the Creator of the
Universe, by a direct act of his "Will, so disposed
the natural forces influencing the growth of this one

C5 O

species of plant as to cause its nectary to increase to
this enormous length; and at the same time, by an
equally special act, determined the flow of nourish-
ment in the organization of the moth, so as to cause
its proboscis to increase in exactly the same propor-
tion, having previously so constructed the AngraBCum
that it could only be maintained in existence by the
agency of this moth. But what proof is given or
suggested that this was the mode by which the ad-
justment took place ? None whatever, except a feel-
ing that there is an adjustment of a delicate kind,
and an inability to see how known causes could have

T 2

27G CREATION BY LAW.

produced such an adjustment. I believe I have
shown, however, that such an adjustment is not only
possible but inevitable, unless at some point or other
we deny the action of those simple laws which we
have already admitted to be but the expressions ot
existing facts.

Adaptation brought about ly General Laws.

It is difficult to find anything like parallel cases in
inorganic nature, but that of a river may perhaps
illustrate the subject in some degree. Let us suppose
a person totally ignorant of Modern Geology to study
carefully a great Kiver System. He finds in its
lower part, a deep broad channel filled to the brim,
flowing slowly through a flat country and carrying
out to the sea a quantity of fine sediment. Higher up
it branches into a number of smaller channels, flow-
ing alternately through flat valleys and between high
banks ; sometimes he finds a deep rocky bed with
perpendicular walls, carrying the water through a
chain of hills; where the stream is narrow he finds
it deep, where wide shallow. Further up still, he
comes to a mountainous region, with hundreds of
streams and rivulets, each with its tributary rills and
gullies, collecting the water from every square mile of
surface, and every channel adapted to the water that it
has to carry. He finds that the bed of every branch,
and stream, and rivulet, has a steeper and steeper slope
as it approaches its sources, and is thus enabled to
carry off the water from heavy rains, and to bear away

CREATION BY LAW. 277

the stones and pebbles and gravel, that would other-
wise block up its course. In every part of this system
he would see exact adaptation of means to an end.
He would say, that this system of channels must have
been designed, it answers its purpose so effectually.
Nothing but a mind could have so exactly adapted
the slopes of the channels, their capacity, and fre-
quency, to the nature of the soil and the quantity of
the rainfall. Again, he would see special adaptation
to the wants of man, in broad quiet navigable rivers
flowing through fertile plains that support a large
population, while the rocky streams and mountain
torrents, were confined to those sterile regions suit-
able only for a small population of shepherds and
herdsmen. He would listen with incredulity to the
Geologist, who assured him, that the adaptation and
adjustment he so admired was an inevitable result of
the action of general laws. That the rains and rivers,
aided by subterranean forces, had modelled the country,
had formed the hills and valleys, had scooped out the
river beds, and levelled the plains ; — and it would only
be after much patient observation and study, after
having watched the minute changes produced year
by year, and multiplying them by thousands and ten
thousands, after visiting the various regions of the
earth and seeing the changes everywhere going on,
and the unmistakable signs of greater changes in past
times, — that he could be made to understand that
the surface of the earth, however beautiful and har-
monious it may appear, is strictly due in every detail

278 CREATION BY LAW.

to the action of forces which are demonstrably self-
adjusting.

Moreover, when he had sufficiently extended his
inquiries, he would find, that every evil effect which
he would imagine must be the result of non-adjust-
ment does somewhere or other occur, only it is not
always evil. Looking on a fertile valley, he would
perhaps say — " If the channel of this river were not
well adjusted, if for a few miles it sloped the wrong
way, the water could not escape, and all this luxuri-
ant valley, full of human beings, would become a
waste of waters." Well, there are hundreds of such
cases. Every lake is a valley " wasted by water,"
and in some cases (as the Dead Sea) it is a positive
evil, a blot upon the harmony and adaptation of the
surface of the earth. Again, he might say — " If rain
did not fall here, but the clouds passed over us to some
other regions, this verdant and highly cultivated plain
would become a desert." And there are such deserts
over a large part of the earth, which abundant rains
would convert into pleasant dwelling-places for man.
Or he might observe some great navigable river,
and reflect how easily rocks, or a steeper channel
in places, might render it useless to man; — and a
little inquiry would show him hundreds of rivers in
every part of the world, which are thus rendered
useless for navigation.

Exactly the same thing occurs in organic nature.
We see some one wonderful case of adjustment, some
unusual development of an organ, but we pass over the

CREATION BY LAW. 279

hundreds of cases in which that adjustment and develop-
ment do not occur. No doubt when one adjustment is
absent another takes its place, because no organism can
continue to exist that is not adjusted to its environ-
ment ; and unceasing variation with unlimited powers
of multiplication, in most cases, furnish the means
of self-adjustment. The world is so constituted, that
by the action of general laws there is produced the
greatest possible variety of surface and of climate ;
and by the action of laws equally general, the greatest
possible variety of organisms have been produced,
adapted to the varied conditions of every part of the
earth. The objector would probably himself admit,
that the varied surface of the earth — the plains and
valleys, the hills and mountains, the deserts and vol-
canoes, the winds and currents, the seas and lakes
and rivers, and the various climates of the earth — are
all the results of general laws acting and re-acting
during countless ages ; and that the Creator does not
appear to guide and control the action of these laws
— here determining the height of a mountain, there
altering the channel of a river — here making the rains
more abundant, there changing the direction of a
current. He would probably admit that the forces of
inorganic nature are self-adjusting, and that the result
necessarily fluctuates about a given mean condition
(which is itself slowly changing), while within certain
limits the greatest possible amount of variety is pro-
duced. If then a '''contriving mind" is not neces-
sary at every step of the process of change eternally

280 CREATION BY LAW.

going on in the inorganic world, why are we re-
quired to believe in the continual action of such
a mind in the region of organic nature ? True, the
laws at work are more complex, the adjustments more
delicate, the appearance of special adaptation more re-
markable; but why should we measure the creative
mind by our own ? Why should we suppose the ma-
chine too complicated, to have been designed by the
Creator so complete that it would necessarily work out
harmonious results ? The theory of a continual inter-
ference" is a limitation of the Creator's power. It
assumes that he could not work by pure law in the
organic, as he has done in the inorganic world ; it
assumes that he could not foresee the consequences
of the laws of matter and mind combined — that re-
sults would continually arise which are contrary to
what is best, and that he has to change what would
otherwise be the course of nature, in order to produce
that beauty, and variety, and harmony, which even we,
with our limited intellects, can conceive to be the
result of self-adjustment in a universe governed by
unvarying law. If we could not conceive the world
of nature to be self-adjusting and capable of endless
development, it would even then be an unworthy idea
of a Creator, to impute the incapacity of our minds
to him; but when many human minds can conceive,
and can even trace out in detail some of the adapta-
tions in nature as the necessary results of unvarying
law, it seems strange that, in the interests of religion,
any one should seek to prove that the System of Na-

CREATION BY LAW. 281

ture, instead of being above, is far below our highest
conceptions of it. I, for one, cannot believe that the
world would come to chaos if left to Law alone. I
cannot believe that there is in it no inherent power
of developing beauty or variety, and that the direct
action of the Deity is required to produce each spot
or streak on every insect, each detail of structure in
every one of the millions of organisms that live or
have .lived upon the earth. For it is impossible to
draw a line. If any modifications of structure could
be the result of law, why not all ? If some self-adapta-
tions could arise, why not others ? If any varieties of
colour, why not all the varieties we see ? No attempt
is made to explain this, except by reference to the fact
that "purpose" and "contrivance" are everywhere
visible, and by the illogical deduction that they could
only have arisen from the direct action of some mind,
because the direct action of our minds produces simi-
lar " contrivances " ; but it is forgotten that adapta-
tion, however produced, must have the appearance
of design. The channel of a river looks as if made
for the river, although it is made ly it ; the fine layers
and beds in a deposit of sand, often look as if they had
been sorted, and sifted, and levelled, designedly; the
sides and angles of a crystal exactly resemble similar
forms designed by man ; but we do not therefore con-
clude that these effects have, in each individual case,
required the directing action of a creative mind, or see
any difficulty in their being produced by natural Law.

282 CREATION BY LAW.

Beauty in Nature.

Let us, however, leave this general argument for
a while, and turn to another special case, which has
been appealed to as conclusive against Mr. Darwin's
views. " Beauty " is, to some persons, as great a
stumbling-block as " contrivance." They cannot con-
ceive a system of the Universe, so perfect, as neces-
sarily to develop every form of Beauty, but suppose
that when anything specially beautiful occurs, it is a
step beyond what that system could have produced,
something which the Creator has added for his own
delectation.

Speaking of the Humming Birds, the Duke of Ar-
gyll says : " In the first place, it is to be observed of
the whole group, that there is no connection which
can be traced or conceived, between the splendour of
the humming birds and any function essential to their
life. If there were any such connection, that splen-
dour could not be confined, as it almost exclusively
is, to only one sex. The female birds are, of course,
not placed at any disadvantage in the struggle for
existence by their more sombre colouring." And after
describing the various ornaments of these birds, he
says : " Mere ornament and variety of form, and these
for their own sake, is the only principle or rule with
reference to which Creative Power seems to have
worked in these wonderful and beautiful birds. . .
A crest of topaz is no better in the struggle for ex-
istence than a crest of sapphire. A frill ending in

CREATION BY LAW. 283

spangles of the emerald is no better in the battle of
life than a frill ending in spangles of the ruby. A tail
is not affected for the purposes of flight, whether its
marginal or its central feathers are decorated with
white. . . Mere beauty and mere variety, for their
own sake, are objects which we ourselves seek when
we can make the Forces of Nature subordinate to the
attainment of them. There seems to be no conceivable
reason why we should doubt or question, that these
are ends and aims also in the forms given to living
organisms" ("Reign of Law," p. 248).

Here the statement that "no connection can be con-
ceived between the splendour of the humming birds
and any function essential to their life," is met by
the fact, that Mr. Darwin has not only conceived
but has shown, both by observation and reasoning,
how beauty of colour and form may have a direct
influence on the most important of all the functions
of life, that of reproduction. In the variations to
which birds are subject, any more brilliant colour
than usual would be attractive to the females, and
would lead to the individuals so adorned leaving more
than the average number of offspring. Experiment
and observation have shown, that this kind of sexual
selection does actually take place ; and the laws of
inheritance would necessarily lead to the further de-
velopment of any individual peculiarity that was at-
tractive, and thus the splendour of the humming birds
is directly connected with their very existence. It is
true that " a crest of topaz may be no better than a

284 CREATION BY LAW.

crest of sapphire," but either of these may be much
better than no crest at all ; and the different conditions
under which the parent form must have existed in
different parts of its range, will have determined dif-
ferent variations of tint, either of which were ad-
vantageous. The reason why female birds are not
adorned with equally brilliant plumes is sufficiently
clear ; they would be injurious, by rendering their pos-
sessors too conspicuous during incubation. Survival
of the fittest, has therefore favoured the development
of those dark green tints on the upper surface of so
many female humming birds, which are most conducive
to their protection while the important functions of
hatching and rearing the young are being carried on.
Keeping in mind the laws of multiplication, variation,
and survival of the fittest, which are for ever in action,
these varied developments of beauty and harmonious
adjustments to conditions, are not only conceivable
but demonstrable results.

The objection I am now combating is solely founded
on the supposed analogy of the Creator's mind to
ours, as regards the love of Beauty for its own sake ;
but if this analogy is to be trusted, then there ought
to be no natural objects which are disagreeable or
ungraceful in our eyes. And yet it is undoubtedly
the fact that there are many such. Just as surely
as the Horse and Deer are beautiful and graceful,
the Elephant, Rhinoceros, Hippopotamus, and Camel
are the reverse. The majority of Monkeys and Apes
are not beautiful ; the majority of Birds have no beauty

CREATION ZY LAW. 285

of colour ; a vast number of Insects and Reptiles are
positively ugly. Now, if the Creator's mind is like
ours, whence this ugliness? It is useless to say "that
is a mystery we cannot explain," because we have
attempted to explain one-half of creation by a method
that will not apply to the other half. We know that
a man with the highest taste and with unlimited
wealth, practically does abolish all ungraceful and dis-
agreeable forms and colours from his own domains.
If the beauty of creation is to be explained by the
Creator's love of beauty, we are bound to ask why
he has not banished deformity from the earth, as the
wealthy and enlightened man does from his estate and
from his dwelling ; and if we can get no satisfactory
answer, we shall do well to reject the explanation
offered. Ao-ain, in the case of flowers, which are

O / '

always especially referred to, as the surest evidence of
beauty being an end of itself in creation, the whole
of the facts are never fairly met. At least half the
plants in the world have not bright-coloured or beau-
tiful flowers ; and Mr. Darwin has lately arrived at
the wonderful generalization, that flowers have become
beautiful solely to attract insects to assist in their
fertilization. He adds, " I have come to this conclu-
sion from finding it an invariable rule, that when a
flower is fertilized by the wind it never has a gaily-
coloured corolla." Here is a most wonderful case of
beauty being useful^ when it might be least expected.
But much more is proved ; for when beauty is of no
use to the plant it is not given. It cannot be imag-

286 CREATION BY LAW.

ined to do any harm. It is simply not necessary, and
is therefore withheld ! We ought surely to have been
told how this fact is consistent with beauty being " an
end in itself," and with the statement of its being
given to natural objects " for its own sake."

How new Forms are produced l>y Variation and
Selection.

Let us now consider another of the popular objec-
tions which the Duke of Argyll thus sets forth : —

a Mr. Darwin does not pretend to have discovered
any law or rule, according to which new Forms have
been born from old Forms. He does not hold that
outward conditions, however changed, are sufficient to
account for them. . . His theory seems to be far
better than a mere theory — to be an established scien-
tific truth — in so far as it accounts, in part at least,
for the success and establishment and spread of new
Forms when tliey have arisen. But it does not even
suggest the law under which, or by or according to
which, such new Forms are introduced. Natural Se-
lection can do nothing, except with the materials
presented to its hands. It cannot select except among
the things open to selection. . . Strictly speaking,
therefore, Mr. Darwin's theory is not a theory on
the Origin of Species at all, but only a theory on the
causes which lead to the relative success or failure
of such new forms as may be born into the world."
(" Reign of Law," p. 230.)

In this, and many other passages in his work, the

CREATION BY LAW. 287

Duke of Argyll sets forth his idea of Creation as a
" Creation by birth," but maintains that each birth
of a new form from parents differing from itself, has
been produced by a special interference of the Creator,
in order to direct the process of development into
certain channels ; that each new species is in fact a
"special creation," although brought into existence
through the ordinary laws of reproduction. He main-
tains therefore, that the laws of multiplication and
variation cannot furnish the right kinds of materials
at the right times for natural selection to work on.
I believe, on the contrary, that it can be logically
proved from the six axiomatic laws before laid down,
that such materials would be furnished ; but I prefer
to show there are abundance of facts which demon-
strate that they are furnished.

The experience of all cultivators of plants and
breeders of animals shows, that when a sufficient
number of individuals are examined, variations of
any required kind can always be met with. On
this depends the possibility of obtaining breeds, races,
and fixed varieties of animals and plants; and it is
found, that any one form of variation may be accu-
mulated by selection, without materially affecting the
other characters of the species ; each seems to vary
in the one required direction only. For example, in
turnips, radishes, potatoes, and carrots, the root or
tuber varies in size, colour, form, and flavour, while
the foliage and flowers seem to remain almost sta-
tionary ; in the cabbage and lettuce, on the contrary,

288 CREATION BY LAW.

the foliage can bo modified into various forms and
modes of growth, the root, flower, and fruit remain-
ing little altered ; in the cauliflower and brocoli the
flower heads vary ; in the garden pea the pod only
changes. We get innumerable forms of fruit in the
apple and pear, while the leaves and flowers remain
undistinguishable ; the same occurs in the gooseberry
and garden currant. Directly however, (in the very
same genus) we want the flower to vary in the Ribes
sanguineum, it does so, although mere cultivation
for hundreds of years has not produced marked dif-
ferences in the flowers of Ribes grossularia. When
fashion demands any particular change in the form
or size, or colour of a flower, sufficient variation
always occurs in the right direction, as is shown by
our roses, auriculas, and geraniums ; when, as re-
cently, ornamental leaves come into fashion sufficient
variation is found to meet the demand, and we have
zoned pelargoniums, and variegated ivy, and it is
discovered that a host of our commonest shrubs and
herbaceous plants have taken to vary in this direction
just when we want them to do so ! This rapid varia-
tion is not confined to old and well-known plants
subjected for a long series of generations to culti-
vation, but the Sikim Rhododendrons, the Fuchsias,
and Calceolarias from the Andes, and the Pelargoniums
from the Cape are equally accommodating, and vary
just when and where and how we require them.

Turning to animals we find equally striking exam-
ples. If we want any special quality in any animal

CREATION BY LAW. 289

we have only to breed it in sufficient quantities and
watch carefully, and the required variety is always
found, and can be increased to almost any desired ex-
tent. In Sheep, we get flesh, fat, and wool ; in Cows,
milk ; in Horses, colour, strength, size, and speed ; in
Poultry, we have got almost any variety of colour,
curious modifications of plumage, and the capacity of
perpetual egg-laying. In Pigeons we have a still
more remarkable proof of the universality of varia-
tion, for it has been at one time or another the fancy
of breeders to change the form of every part of
these birds, and they have never found the required
variations absent. The form, size, and shape of bill
and feet, have been changed to such a degree as is
found only in distinct genera of wild birds ; the num-
ber of tail feathers has been increased, a character
which is generally one of the most permanent nature,
and is of high importance in the classification of
birds ; and the size, the colour, and the habits, have
been also changed to a marvellous extent. In Dogs,
the degree of modification and the facility with which
it is effected, is almost equally apparent. Look at
the constant amount of variation in opposite direc-
tions that must have been going on, to develop the
poodle and the greyhound from the same original
stock ! Instincts, habits, intelligence, size, speed,
form, and colour, have always varied, so as to produce
the very races which the wants or fancies or passions
of men may have led them to desire. Whether they
wanted a bull-dog to torture another animal, a grey-

u

290 CREATION BY LAW.

hound to catch a hare, or a bloodhound to hunt down
their oppressed fellow-creatures, the required varia-
tions have always appeared.

Now this great mass of facts, of which a mere
sketch has been here given, are fully accounted for
by the " Law of Variation " as laid down at the
commencement of this paper. Universal variability —
small in amount but in every direction, ever fluctuat-
ing about a mean condition until made to advance in
a given direction by " selection," natural or artificial,
— is the simple basis for the indefinite modification
of the forms of life ; — partial, unbalanced, and con-
sequently unstable modifications being produced by
man, while those developed under the unrestrained
action of natural laws, are at every step self-adjusted
to external conditions by the dying out of all unad-
justed forms, and are therefore stable and compara-
tively permanent. To be consistent in their views, our
opponents must maintain that every one of the varia-
tions that have rendered possible the changes produced
by man, have been determined at the right time and
place by the will of the Creator. Every race produced
by the florist or the breeder, the dog or the pigeon
fancier, the ratcatcher, the sporting man, or the slave-
hunter, must have been provided for by varieties occur-
ring when wanted ; and as these variations were never
withheld, it would prove, that the sanction of an all-
wise and all-powerful Being, has been given to that
which the highest human minds consider to be trivial,
mean, or debasing.

CREATION BY LAW. 291

This appears to be a complete answer to the theory,
that variation sufficient in amount to be accumulated
in a given direction must be the direct act of the
Creative Mind, but it is also sufficiently condemned
by being so entirely unnecessary. The facility with
which man obtains new races, depends chiefly upon
the number of individuals he can procure to select
from. When hundreds of florists or breeders are all
aiming at the same object, the work of change goes on
rapidly. But a common species in nature contains a
thousand- or a million-fold more individuals than any
domestic race ; and survival of the fittest must unerr-
ingly preserve all that vary in the right direction,
not only in obvious characters but in minute details,
not only in external but in internal organs ; so that
if the materials are sufficient for the needs of man,
there can be no want of them to fulfil the grand pur-
pose of keeping up a supply of modified organisms,
exactly adapted to the changed conditions that are
always occurring in the inorganic world.

The Objection that there are Limits to Variation.

Having now, I believe, fairly answered the chief ob-
jections of the Duke of Argyll, I proceed to notice one
or two of those adduced in an able and argumentative
essay on the " Origin of Species " in the North British
Review for July, 1867. The writer first attempts to
prove that there are strict limits to variation. When
we begin to select variations in any one direction, the
process is comparatively rapid, but after a considerable

u 2

292 CEEATION EY LAW.

amount of change has been effected it becomes slower
and slower, till at length its limits are reached and no
care in breeding and selection can produce any further
advance. The race-horse is chosen as an example.
It is admitted that, with any ordinary lot of horses
to begin with, careful selection would in a few years
make a great improvement, and in a comparatively
short time the standard of our best racers might be
reached. But that standard has not for many years
been materially raised, although unlimited wealth and
energy are expended in the attempt. This is held to
prove that there are definite limits to variation in any
special direction, and that we have no reason to sup-
pose that mere time, and the selective process being
carried on by natural law, could make any material
difference. But the writer does not perceive that this
argument fails to meet the real question, which is, not
whether indefinite and unlimited change in any or all
directions is possible, but whether such differences as
do occur in nature could have been produced by the
accumulation of variations by selection. In the matter
of speed, a limit of a definite kind as regards land
animals does exist in nature. All the swiftest animals
— deer, antelopes, hares, foxes, lions, leopards, horses,
zebras, and many others, have reached very nearly the
same degree of speed. Although the swiftest of each
must have been for ages preserved, and the slowest
must have perished, we have no reason to believe
there is any advance of speed. The possible limit
under existing conditions, and perhaps under possible

CEEATION BY LAW. 293

terrestrial conditions, has been long ago reached.
In cases, however, where this limit had not been so
nearly reached as in the horse, we have been enabled
to make a more marked advance and to produce a
greater difference of form. The wild dog is an animal
that hunts much in company, and trusts more to en-
durance than to speed. Man has produced the grey-
hound, which differs much more from the wolf or the
dingo than the racer does from the wild Arabian.
Domestic dogs, again, have varied more in size and
in form than the whole family of Canidae in a state
of nature. No wild dog, fox, or wolf, is either so
small as some of the smallest terriers and spaniels,
or so large as the largest varieties of hound or New-
foundland dog. And, certainly, no two wild animals
of the family differ so widely in form and proportions
as the Chinese pug and the Italian greyhound, or the
bulldog and the common greyhound. The known range
of variation is, therefore, more than enough for the
derivation of all the forms of Dogs, Wolves, and Foxes
from a common ancestor.

Again, it is objected that the Pouter or the Fan-
tail pigeon cannot be further developed in the same
direction. Variation seems to have reached its limits
in these birds. But so it has in nature. The Fan-
tail has not only more tail feathers than any of the
three hundred and forty existing species of pigeons,
but more than any of the eight thousand known
species of birds. There is, of course, some limit to
the number of feathers of which a tail useful for flight

294 CREATION BY LAW.

can consist, and in the Fan-tail we have probably
reached that limit. Many birds have the oesophagus
or the skin of the neck more or less dilatable, but in
no known bird is it so dilatable as in the Pouter
pigeon. Here again the possible limit, compatible
with a healthy existence, has probably been reached.
In like manner the differences in the size and form
of the beak in the various breeds of the domestic
Pigeon, is greater than that between the extreme
forms of beak in the various genera and sub-families
of the whole Pigeon tribe. From these facts, and
many others of the same nature, we may fairly infer,
that if rigid selection were applied to any organ, we
could in a, comparatively short time produce a much
greater amount of change than that which occurs be-
tween species and species in a state of nature, since
the differences which we do produce are often com-
parable with those which exist between distinct genera
or distinct families. The facts adduced by the writer
of the article referred to, of the definite limits to va-
riability in certain directions in domesticated animals,
are, therefore, no objection whatever to the view, that
all the modifications which exist in nature have been
produced by the accumulation, by natural selection, of
small and useful variations, since those very modifi-
cations have equally definite and very similar limits.

Objection to the Argument from Classification.

To another of this writer's . objections — that by Pro-
fessor Thomson's calculations the sun can only have

CREATION BY LAW. 295

existed in a solid state 500,000,000 of years, and
that therefore time would not suffice for the slow pro-
cess of development of all living organisms — it is
hardly necessary to reply, as it cannot be seriously
contended, even if this calculation has claims to ap-
proximate accuracy, that the process of change and
development may not have been sufficiently rapid to
have occurred within that period. His objection to
the Classification argument is, however, more plau-
sible. The uncertainty of opinion among Naturalists
as to which are species and which varieties, is one of
Mr. Darwin's very strong arguments that these two
names cannot belong to things quite distinct in nature
and origin. The Reviewer says that this argument is of
no weight, because the works of man present exactly
the same phenomena; and he instances patent inven-
tions, and the excessive difficulty of determining whether
they are new or old. I accept the analogy though it
is a very imperfect one, and maintain that such as it
is, it is all in favour of Mr. Darwin's views. For
are not all inventions of the same kind directly affili-
ated to a common ancestor? Are not improved Steam
Engines or Clocks the lineal descendants of some ex-
isting Steam Engine or Clock ? Is there ever a new
Creation in Art or Science any more than in Nature ?
Did ever patentee absolutely originate any complete
and entire invention, no portion of which was derived
from anything that had been made or described be-
fore ? It is therefore clear that the difficulty of dis-
tinguishing the various classes of inventions which

296 CREATION BY LAW.

claim to be new, is of the same nature as the difficulty
of distinguishing varieties and species, because neither
are absolute new creations, but both are alike de-
scendants of pre-existing forms, from which and from
each other they differ by varying and often imper-
ceptible degrees. It appears, then, that however plau-
sible this writer's objections may seem, whenever he
descends from generalities to any specific statement,
his supposed difficulties turn out to be in reality
strongly confirmatory of Mr. Darwin's view.

TIte " Times," on Natural Selection.

The extraordinary misconception of the whole sub-
ject by popular writers and reviewers, is well shown
by an article which appeared in the Times news-
paper on (t The Reign of Law." Alluding to the
supposed economy of nature, in the adaptation of
each species to its own place and its special use, the
reviewer remarks : "To this universal law of the
greatest economy, the law of natural selection stands
in direct antagonism as the law of ' greatest possible
waste ' of time and of creative power. To conceive
a duck with webbed feet and a spoon-shaped bill,
living by suction, to pass naturally into a gull with
webbed feet and a knife-like bill, living on flesh, in
the longest possible time and in the most laborious
possible way, we may conceive it to pass from the
one to the other state by natural selection. The battle
of life the ducks will have to fight will increase in
peril continually as they cease (with the change of

CREATION BY LAW. 297

their bill) to be ducks, and attain a maximum of
danger in the condition in which they begin to be
gulls ; and ages must elapse and whole generations
must perish, and countless generations of the one
species be created and sacrificed, to arrive at one
single pair of the other."

In this passage the theory of natural selection is
so absurdly misrepresented that it would be amusing,
did we not consider the misleading effect likely to
be produced by this kind of teaching in so popular
a journal. It is assumed that the duck and the gull
are essential parts of nature, each well fitted for its
place, and that if one had been produced from the
other by a gradual metamorphosis, the intermediate
forms would have been useless, unmeaning, and un-
fitted for any place, in the system of the universe.
Now, this idea can only exist in a mind ignorant
of the very foundation and essence of the theory of
natural selection, which is, the preservation of useful
variations only, or, as has been well expressed, in
other words, the " survival of the fittest." Every
intermediate form which could possibly have arisen
during the transition from the duck to the gull, so
far from having an unusually severe battle to fight
for existence, or incurring any a maximum of danger,"
would necessarily have been as accurately adjusted
to the rest of nature, and as well fitted to maintain
and to enjoy its existence, as the duck or the gull
actually are. If it were not so, it never could have
been produced under the law of natural selection.

298 CREATION BY LAW.

Intermediate or generalized Forms of extinct Animals,
an indication of Transmutation or Development.

The misconception of this writer illustrates another
point very frequently overlooked. It is an essential
part of Mr. Darwin's theory, that one existing animal
has not been derived from any other existing animal,
but that both are the descendants of a common an-
cestor, which was at once different from either, but,
in essential characters, intermediate between them both.
The illustration of the duck and the gull is therefore
misleading ; one of these birds has not been derived
from the other, but both from a common ancestor.
This is not a mere supposition invented to support the
theory of natural selection, but is founded on a variety
of indisputable facts. As we go back into past time,
and meet with the fossil remains of more and more
ancient races of extinct animals, we find that many
of them actually are intermediate between distinct
groups of existing animals. Professor Owen con-
tinually dwells on this fact : he says in his " Paleon-
tology," p. 284 : "A more generalized vertebrate
structure is illustrated, in the extinct reptiles, by
the affinities to ganoid fishes, shown by Ganocephala,
Labyrinthodontia, and Icthyopterygia ; by the affinities
of the Pterosauria to Birds, and by the approximation
of the Dinosauria to Mammals. (These have been re-
cently shown by Professor Huxley to have more affinity
to Birds.) It is manifested by the combination of
modern crocodilian, chelcnian, and lacertian characters

CREATION BY LAW. 299

in the Cryptodontia and the Dicnyodontia, and by the
combined lacertian and crocodilian characters in the
Thecodontia and Sauropterygia." In the same work
he tells us that, " the Anoplotherium, in several im-
portant characters resembled the embryo Ruminant,
but retained throughout life those marks of adhesion
to a generalized mammalian type ;" — and assures us
that he has " never omitted a proper opportunity for
impressing the results of observations showing the
more generalized structures of extinct as compared
with the more specialized forms of recent animals."
Modern paleontologists have discovered hundreds of
examples of these more generalized or ancestral types.
In the time of Cuvier, the Ruminants and the Pachy-
derms were looked upon as two of the most distinct
orders of animals ; but it is now demonstrated that
there once existed a variety of genera and species,
connecting by almost imperceptible grades such widely
different animals as the pig and the camel. Among
living quadrupeds we can scarcely find a more isolated
group than the genus Equus, comprising the horses,
asses, and Zebras ; but through many species of Palo-
plotherium, Hippotherium, and Hipparion, and numbers
of extinct forms of Equus found in Europe, India, and
America, an almost complete transition is established
with the Eocene Anoplotherium and Paleotherium,
which are also generalized or ancestral types of the
Tapir and Rhinoceros. The recent researches of M.
Gaudry in Greece have furnished much new evidence
of the same character. In the Miocene beds of Pikermi

300 CREATION BY LAW.

he has discovered the group of the Simocyonidse inter-
mediate between bears and wolves ; the genus Hyasnictis
which connects the hyaenas with the civets ; the Ancylo-
therium, which is allied both to the extinct mastodon
and to the living pangolin or scaly ant-eater ; and
the Helladotherium, which connects the now isolated
giraffe with the deer and antelopes.

Between reptiles and fishes an intermediate type has
been found in the Archegosaurus of the Coal forma-
tion; while the Labyrinthodon of the Trias combined
characters of the Batrachia with those of crocodiles,
lizards, and ganoid fishes. Even birds, the most appa-
rently isolated of all living forms, and the most rarely
preserved in a fossil state, have been shown to possess
undoubted affinities with reptiles ; and in the Oolitic
Archseopteryx, with its lengthened tail, feathered on
each side, we have one of the connecting links from
the side of birds ; while Professor Huxley has recently
shown that the entire order of Dinosaurians have re-
markable affinities to birds, and that one of them, the
Compsognathus, makes a nearer approach to bird orga-
nisation than does Archseopteryx to that of reptiles.

Analogous facts to these occur in other classes of
animals, as an example of which we have the authority
of a distinguished paleontologist, M. Barande, quoted
by Mr. Darwin, for the statement, that although the
Paleozoic Invertebrata can certainly be classed under
existing groups, yet at this ancient period the groups
were not so distinctly separated from each other as
they are now ; while Mr. Scudder tells us, that some of

CREATION BY LAW. 301

the fossil insects discovered in the Coal formation of
America offer characters intermediate between those of
existing orders. Agassiz, again, insists strongly that the
more ancient animals resemble the embryonic forms of
existing species ; but as the embryos of distinct groups
are known to resemble each other more than the adult
animals (and in fact to be undistinguishable at a very
early age), this is the same as saying that the ancient
animals are exactly what, on Darwin's theory, the
ancestors of existing animals ought to be ; and this,
it must be remembered, is the evidence of one of the
strongest opponents of the theory of natural selection.

Conclusion.

I have thus endeavoured to meet fairly, and to an-
swer plainly, a few of the most common objections to
the theory of natural selection, and I have done so in
every case by referring to admitted facts and to logical
deductions from those facts.

As an indication and general summary of the line
of argument I have adopted, I here give a brief de-
monstration in a tabular form of the Origin of Species
by means of Natural Selection, referring for the facts
to Mr. Darwin's works, and to the pages in this volume,
where they are more or less fully treated.

302

CREATION BY LAW.

A Demonstration of the Origin of Species by Natural
Selection.

PROVED FACTS.

RAPID INCREASE OP ORGAN-
ISMS, pp. 29, 265 ; (" Origin
of Species," p. 75, 5th Ed.)

TOTAL NUMBER OP INDIVI-
DUALS STATIONARY, pp. 30,
266.

STRUGGLE FOR EXISTENCE.

HEREDITY WITH VARIATION,
or general likeness with
individual differences of pa-
rents and offspring, pp.
266,287-291,308; ("Origin
of Species," chap. I., II., V.)

SURVIVAL OF THE FITTEST.

CHANGE OF EXTERNAL CON-
DITIONS, universal and un-
ceasing. — See " Ly ell's
Principles of Geology."

NECESSARY CONSEQUENCES
(afterwards taken as Proved Facts).

STRUGGLE FOR EXISTENCE,
the deaths equalling the
births on the average, p. 30 ;
(" Origin of Species," chap.
III.)

SURVIVAL OF THE FITTEST,
or Natural Selection; mean-
ing simply, that on the
whole those die who are
least fitted to maintain their
existence ; (" Origin of Spe-
cies," chap. IV.)

CHANGES OP ORGANIC FORMS,
to keep them in harmony
with the Changed Condi-
tions ; and as the changes
of conditions are perma-
nent changes, in the sense
of not reverting back to
identical previous condi-
tions, the changes of or-
ganic forms must be in the
same sense permanent, and
thus originate SPECIES.

303

IX.

THE DEVELOPMENT OF HUMAN RACES
UNDER THE LAW OF NATURAL SELEC-
TION.

AMONG the most advanced students of man, there exists
a wide difference of opinion on some of the most vital
questions respecting his nature and origin. Anthro-
pologists are now, indeed, pretty well agreed that man
is not a recent introduction into the earth. All who
have studied the question, now admit that his anti-
quity is very great ; and that, though we have to some
extent ascertained the minimum of time during which
he must have existed, we have made no approximation
towards determining that far greater period during
which he may have, and probably has existed. We
can with tolerable certainty affirm that man must have
inhabited the earth a thousand centuries ago, but we
cannot assert that he positively did not exist, or that
there is any good evidence against his having existed,
for a period of ten thousand centuries. We know
positively, that he was contemporaneous with many
now extinct animals, and has survived changes of the
earth's surface fifty or a hundred times greater than
any that have occurred during the historical period ;
but we cannot place any definite limit to the number

304 THE ACI10N OF NATURAL

of species he may have outlived, or to the amount of
terrestrial change he may have witnessed.

Wide differences of opinion as to Mail's Origin.

But while on this question of man's antiquity there
is a very general agreement, — and all are waiting
eagerly for fresh evidence to clear up those points
which all admit to be full of doubt, — on other, and
not less obscure and difficult questions, a considerable
amount of dogmatism is exhibited ; doctrines are put
forward as established truths, no doubt or hesitation
is admitted, and it seems to be supposed that no
further evidence is required, or that any new facts
can modify our convictions. This is especially the case
when we inquire, — Are the various forms under which
man now exists primitive, or derived from pre-exist-
ing forms ; in other words, is man of one or many
species ? To this question we immediately obtain dis-
tinct answers diametrically opposed to each other : the
one party positively maintaining, that man is a species
and is essentially one — that all differences are but local
and temporary variations, produced by the different
physical and moral conditions by which he is sur-
rounded ; the other party maintaining with equal con-
fidence, that man is a genus of many species, each of
which is practically unchangeable, and has ever been
as distinct, or even more distinct, than we now be-
hold them. This difference of opinion is somewhat
remarkable, when we consider that both parties are
well acquainted with the subject ; both use the same

SELECTION ON MAN. 305

vast accumulation of facts ; both reject those early
traditions of mankind which profess to give an ac-
count of his origin ; and both declare that they aro
seeking fearlessly after truth alone ; yet each will
persist in looking only at the portion of truth on
his own side of the question, and at the error which
is mingled with his opponent's doctrine. It is my
wish to show how the two opposing views can be
combined, so as to eliminate the error and retain the
truth in each, and it is by means of Mr. Darwin's
celebrated theory of " Natural Selection " that I hope
to do this, and thus to harmonise the conflicting

' O

theories of modern anthropologists.

Let us first see what each party has to say for
itself. In favour of the unity of mankind it is argued,
that there are no races without transitions to others ;
that every race exhibits within itself variations of
colour, of hair, of feature, and of form, to such a de-
gree as to bridge over, to a large extent, the gap that
separates it from other races. It is asserted that no
race is homogeneous ; that there is a tendency to vary ;
that climate, food, and habits produce, and render
permanent, physical peculiarities, which, though slight
in the limited periods allowed to our observation, would,
in the long ages during which the human race has ex-
isted, have sufficed to produce all the differences that
now appear. It is further asserted that the advocates
of the opposite theory do not agree among themselves ;
that some would make three, some five, some fifty or
a hundred and fifty species of man ; some would have

X

306 THE ACTION OF NATUEAL

had each species created in pairs, while others require
nations to have at once sprung into existence, and
that there is no stability or consistency in any doctrine
but that of one primitive stock.

The advocates of the original diversity of man, on
the other hand, have much to say for themselves.
They argue that proofs of change in man have never
been brought forward except to the most trifling
amount, while evidence of his permanence meets us
everywhere. The Portuguese and Spaniards, settled
for two or three centuries in South America, retain
their chief physical, mental, and moral characteristics ;
the Dutch boers at the Cape, and the descendants of
the early Dutch settlers in the Moluccas, have not lost
the features or the colour of the Germanic races ; the
Jews, scattered over the world in the most diverse
climates, retain the same characteristic lineaments
everywhere ; the Egyptian sculptures and paintings
show us that, for at least 4000 or 5000 years, the
strongly contrasted features of the Negro and the
Semitic races have remained altogether unchanged ;
while more recent discoveries prove, that the mound-
builders of the Mississippi valley, and the dwellers
on Brazilian mountains, had, even in the very in-
fancy of the human race, some traces of the same
peculiar and characteristic type of cranial formation
that now distinguishes them.

If we endeavour to decide impartially on the merits
of this difficult controversy, judging solely by the evi-
dence that each party has brought forward, it certainly

SELECTION ON MAN. 307

seems that the best of the argument is on the side of
those who maintain the primitive diversity of man.
Their opponents have not been able to refute the per-
manence of existing races as far back as we can trace
them, and have failed to show, in a single case, that
at any former epoch the well marked varieties of man-
kind approximated more closely than they do at the
present day. At the same time this is but negative
evidence. A condition of immobility for four or five
thousand years, does not preclude an advance at an
earlier epoch, and — if we can show that there are
causes in nature which would check any further phy-
sical change when certain conditions were fulfilled —
does not even render such an advance improbable, if
there are any general arguments to be adduced in its
favour. Such a cause, I believe, does exist ; and I
shall now endeavour to point out its nature and its
mode of operation.

Outline of the Theory of Natural Selection.

In order to make my argument intelligible, it is
necessary for me to explain very briefly the theory of
" Natural Selection " promulgated by Mr. Darwin,
and the power which it possesses of modifying the
forms of animals and plants. The grand feature in
the multiplication of organic life is, that close general
resemblance is combined with more or less individual
variation. The child resembles its parents or ancestors
more or less closely in all its peculiarities, deformities,
or beauties ; it resembles them in general more than it

x 2

308 THE ACTION OF NATURAL

does any other individuals ; yet children of the same
parents are not all alike, and it often happens that
they differ very considerably from their parents and
from each ether. This is equally true, of man, of all
animals, and of all plants. Moreover, it is found that
individuals do not differ from their parents in certain
particulars only, while in all others they are exact
duplicates of them. They differ from them and from
each other, in every particular: in form, in size, in
colour ; in the structure of internal as well as of external
organs ; in those subtle peculiarities which produce
differences of constitution, as well as in those still more
subtle ones which lead to modifications of mind and
character. In other words, in every possible way, in
every organ and in every function, individuals of the
same stock vary.

Now, health, strength, and long life, are the results
of a harmony between the individual and the universe
that surrounds it. Let us suppose that at any given
moment this harmony is perfect. A certain animal is
exactly fitted to secure its prey, to escape from its
enemies, to resist the inclemencies of the seasons, and
to rear a numerous and healthy offspring. But a
change now takes place. A series of cold winters, for
instance, come on, making food scarce, and bringing
an immigration of some other animals to compete with
the former inhabitants of the district. The new immi-
grant is swift of foot, and surpasses its rivals in the
pursuit of game; the winter nights are colder, and
require a thicker fur as a protection, and more

SELECTION ON MAN. 309

nourishing food to keep up the heat of the system.
Our supposed perfect animal is no longer in harmony
with its universe ; it is in danger of dying of cold or
of starvation. But the animal varies in its offspring.
Some of these are swifter than others — they still
manage to catch food enough; some are hardier and
more thickly furred — they manage in the cold nights to
keep warm enough ; the slow, the weak, and the thinly
clad soon die off. Again and again, in each succeed-
ing generation, the same thing takes place. By this
natural process, which is so inevitable that it cannot
be conceived not to act, those best adapted to live, live ;
those least adapted, die. It is sometimes said that we
have no direct evidence of the action of this selecting
power in nature. But it seems to me we have better
evidence than even direct observation would be, because
it is more universal, viz., the evidence of necessity.
It must be so ; for, as all wild animals increase in a
geometrical ratio, while their actual numbers remain
on the average stationary, it follows, that as many die
annually as are born. If, therefore, we deny natural
selection, it can only be by asserting that, in such a
case as I have supposed, the strong, the healthy, the
swift, the well clad, the well organised animals in
every respect, have no advantage over, — do not on the
average live longer than, the weak, the unhealthy, the
slow, the ill-clad, and the imperfectly organised indi-
viduals ; and this no sane man has yet been found
hardy enough to assert. But this is not all ; for the
offspring on the average resemble their parents, and

310 THE ACTION OF NATURAL

the selected portion of each succeeding generation will
therefore be stronger, swifter, and more thickly furred
than the last ; and if this process goes on for thousands
of generations, our animal will have again become
thoroughly in harmony with the new conditions in
which it is placed. But it will now be a different
creature. It will be not only swifter and stronger,
and more furry, it will also probably have changed in
colour, in form, perhaps have acquired a longer tail,
or differently shaped ears ; for it is an ascertained
fact, that when one part of an animal is modified,
some other parts almost always change, as it were in
sympathy with it. Mr. Darwin calls this " correlation
of growth," and gives as instances, that hairless dogs
have imperfect teeth ; white cats, wrhen blue-eyed, are
deaf; small feet accompany short beaks in pigeons ;
and other equally interesting cases.

Grant, therefore, the premises : 1st. That peculiari-
ties of every kind are more or less hereditary. 2nd.
That the offspring of every animal vary more or less
in all parts of their organization. 3rd. That the
universe in which these animals live, is not absolutely
invariable ; — none of which propositions can be denied ;
and then consider, that the animals in any country
(those at least which are not dying out) must at each
successive period be brought into harmony with the
surrounding conditions ; and we have all the elements
for a change of form and structure in the animals,
keeping exact pace with changes of whatever nature
in the surrounding universe. Such changes must be

SELECTION ON MAN. 311

slow, for the changes in the universe are very slow ;
but just as these slow changes become important, when
we look at results after long periods of action, as we
do when we perceive the alterations of the earth's sur-
face during geological epochs; so the parallel changes
in animal form become more and more striking, in.
proportion as the time they have been going on is
great ; as we see when we compare our living animals
with those which we disentomb from each successively
older geological formation.

This is, briefly, the theory of " natural selection,"
which explains the changes in the organic world as
being parallel with, and in part dependent on, those in
the inorganic. What we now have to inquire is, —
Can this theory be applied in any way to the question
of the origin of the races of man ? or is there anything
in human nature that takes him out of the category
of those organic existences, over whose successive
mutations it has had such powerful sway ?

Different effects of Natural Selection on Animals and
on Man.

In order to answer these questions, we must consider
why it is that a natural selection " acts so powerfully
upon animals ; and we shall, I believe, find, that its
effect depends mainly upon their self-dependence and
individual isolation. A slight injury, a temporary
illness, will often end in death, because it leaves the
individual powerless against its enemies. If an herbi-
vorous animal is a little sick and has not fed well for a

312 THE ACTION OF NATURAL

day or two, and the herd is then pursued by a beast of
prey, our poor invalid inevitably falls a victim. So, in
a carnivorous animal, the least deficiency of vigour pre-
vents its capturing food, and it soon dies of starvation.
There is, as a general rule, no mutual assistance
between adults, which enables them to tide over a
period of sickness. Neither is there any division of
labour; each must fulfil all the conditions of its
existence, and, therefore, " natural selection " keeps
all up to a pretty uniform standard.

But in man, as we now behold him, this is different.
He is social and sympathetic. In the rudest tribes
the sick are assisted, at least with food ; less robust
health and vigour than the average does not entail
death. Neither does the want of perfect limbs, or
other organs, produce the same effects as among ani-
mals. Some division of labour takes place ; the swiftest
hunt, the less active fish, or gather fruits ; food is, to
some extent, exchanged or divided. The action of
natural selection is therefore checked ; the weaker, the
dwarfish, those of less active limbs, or less piercing
eyesight, do not suffer the extreme penalty which falls
upon animals so defective.

In proportion as these physical characteristics be-
come of less importance, mental and moral qualities
will have increasing influence on the well-being of
the race. Capacity for acting in concert for pro-
tection, and for the acquisition of food and shelter ;
sympathy, which leads all in turn to assist each other ;
the sense of right, which checks depredations upon our

SELECTION ON MAN. 313

fellows ; the smaller development of the combative and
destructive propensities ; self-restraint in present appe-
tites ; and that intelligent foresight which prepares for
the future, are all qualities, that from their earliest
appearance must have been for the benefit of each
community, and would, therefore, have become the
subjects of " natural selection." For it is evident
that such qualities would be for the well-being of
man ; would guard him against external enemies,
against internal dissensions, and against the effects of
inclement seasons and impending famine, more surely
than could any merely physical modification. Tribes
in which such mental and moral qualities were pre-
dominant, would therefore have an advantage in the
struggle for existence over other tribes in which they
were less developed, would live and maintain their
numbers, while the others would decrease and finally
succumb.

Again, when any slow changes of physical geogra-
phy, or of climate, make it necessary for an animal
to alter its food, its clothing, or its weapons, it can
only do so by the occurrence of a corresponding
change in its own bodily structure and internal or-
ganization. If a larger or more powerful beast is to
be captured and devoured, as when a carnivorous ani-
mal which has hitherto preyed on antelopes is obliged
from their decreasing numbers to attack buffaloes, it
is only the strongest who can hold, — those with most
powerful claws, and formidable canine teeth, that can
struggle with and overcome such an animal. Natural

314 THE ACTION OF NATURAL

selection immediately comes into play, and by its
action these organs gradually become adapted to their
new requirements. But man, under similar circum-
stances, does not require longer nails or teeth, greater
bodily strength or swiftness. He makes sharper spears,
or a better bow, or he constructs a cunning pitfall,
or combines in a hunting party to circumvent his
new prey. The capacities which enable him to do this
are what he requires to be strengthened, and these
will, therefore, be gradually modified by " natural se-
lection," while the form and structure of his body will
remain unchanged. So, when a glacial epoch comes
on, some animals must acquire warmer fur, or a cover-
ing of fat, or else die of cold. Those best clothed by
nature are, therefore, preserved by natural selection.
Man, under the same circumstances, will make him-
self warmer clothing, and build better houses ; and
the necessity of doing this will react upon his mental
organization and social condition — will advance them
while his natural body remains naked as before.

When the accustomed food of some animal becomes
scarce or totally fails, it can only exist by becoming
adapted to a new kind of food, a food perhaps less
nourishing and less digestible. " Natural selection "
will now act upon the stomach and intestines, and all
their individual variations will be taken advantage of,
to modify the race into harmony with its new food.
In many cases, however, it is probable that this can-
not be done. The internal organs may not vary quick
enough, and then the animal will decrease in numbers,

SELECTION ON MAN. 315

and finally become extinct. But man guards himself
from such accidents by superintending and guiding
the operations of nature. He plants the seed of his
most agreeable food, and thus procures a supply, in-
dependent of the accidents of varying seasons or na-
tural extinction. He domesticates animals, which serve
him either to capture food or for food itself, and thus,
changes of any great extent in his teeth or digestive
organs are rendered unnecessary. Man, too, has every-
where the use of fire, and by its means can render
palatable a variety of animal and vegetable substances,
which he could hardly otherwise make use of; and thus
obtains for himself a supply of food far more varied and
abundant than that which any animal can command.

Thus man, by the mere capacity of clothing him-
self, and making weapons and tools, has taken away
from nature that power of slowly but permanently
changing the external form and structure, in accord-
ance with changes in the external world, which she
exercises over all other animals. As the competing
races by which they are surrounded, the climate, the
vegetation, or the animals which serve them for food,
are slowly changing, they must undergo a corre-
sponding change in their structure, habits, and con-
stitution, to keep them in harmony with the new
conditions — to enable them to live and maintain their
numbers. But man does this by means of his intellect
alone, the variations of which enable him, with an
unchanged body, still to keep in harmony with the
changing universe.

310 THE ACTION OF NATURAL

There is one point, however, in which nature will
still act upon him as it does on animals, and, to some
extent, modify his external characters. Mr. Darwin
has shown, that the colour of the skin is correlated
with constitutional peculiarities both in vegetables and
animals, so that liability to certain diseases or freedom
from them is often accompanied by marked external
characters. Now, there is every reason to believe
that this has acted, and, to some extent, may still
continue to act, on man. In localities where certain
diseases are prevalent, those individuals of savage races
which were subject to them would rapidly die off;
while those who were constitutionally free from the
disease would survive, and form the progenitors of a
new race. These favoured individuals would probably
be distinguished by peculiarities of colour, with which
again peculiarities in the texture or the abundance
of hair seem to be correlated, and thus may have
been brought about those racial differences of colour,
which seem to have no relation to mere temperature
or other obvious peculiarities of climate.

From the time, therefore, when the social and sym-
pathetic feelings came into active operation, and the
intellectual and moral faculties became fairly deve-
loped, man would cease to be influenced by " natural
selection " in his physical form and structure. As an
animal he would remain almost stationary, the changes
of the surrounding universe ceasing to produce in him
that powerful modifying effect which they exercise
over other parts of the organic world. But from the

SELECTION ON MAN. 317

moment that the form of his body became stationary,
his mind would become subject to those very influ-
ences from which his body had escaped ; every slight
variation in his mental and moral nature which should
enable him better to guard against adverse circum-
stances, and combine for mutual comfort and protection,
would be preserved and accumulated ; the better and
higher specimens of our race would therefore increase
and spread, the lower and more brutal would give way
and successively die out, and that rapid advancement
of mental organization would occur, which has raised
the very lowest races of man so far above the brutes
(although differing so little from some of them in
physical structure), and, in conjunction with scarcely
perceptible modifications of form, has developed the
wonderful intellect of the European races.

Influence of external Nature in the development of the
Human Mind.

But from the time when this mental and moral
advance commenced, and man's physical character
became fixed and almost immutable, a new series of
causes would come into action, and take part in his
mental growth. The diverse aspects of nature would
now make themselves felt, and profoundly influence the
character of the primitive man.

When the power that had hitherto modified the body
had its action transferred to the mind, then races would
advance and become improved, merely by the harsh dis-
cipline of a sterile soil a'nd inclement seasons. Under

318 THE ACTION OF NATURAL

their influence, a hardier, a more provident, and a
more social race would be developed, than in those
regions where the earth produces a perennial supply
of vegetable food, and where neither foresight nor
ingenuity are* required to prepare for the rigours of
winter. And is it not the fact that in all ages, and
in every quarter of the globe, the inhabitants of tem-
perate have been superior to those of hotter countries ?
All the great invasions and displacements of races have
been from North to South, rather than the reverse ;
and we have no record of there ever having existed,
any more than there exists to-day, a solitary instance
of an indigenous inter - tropical civilization. The
Mexican civilization and government came from the
North, and, as well as the Peruvian, was established,
not in the rich tropical plains, but on the lofty and
sterile plateaux of the Andes. The religion and civi-
lization of Ceylon were introduced from North India ;
the successive conquerors of the Indian peninsula came
from the North-west ; the northern Mongols conquered
the more Southern Chinese ; and it was the bold and
adventurous tribes of the North that overran and in-
fused new life into Southern Europe.

Extinction of Loiuer Races.

It is the same great law of " the preservation of
favoured races in the struggle for life," which leads
to the inevitable extinction of all those low and
mentally undeveloped populations with which Euro-
peans come in contact. The red Indian in North

SELECTION ON MAN. 319

America, and in Brazil; the Tasmanian, Australian,
and New Zealander in the southern hemisphere, die
out, not from any one special cause, but from the
inevitable effects of an unequal mental and physical
struggle. The intellectual and moral, as well as the
physical, qualities of the European are superior; the
same powers and capacities which have made him
rise in a few centuries from the condition of the
wandering savage with a scanty and stationary popu-
lation, to his present state of culture and advancement,
with a greater average longevity, a greater average
strength, and a capacity of more rapid increase, —
enable him when in contact with the savage man, to
conquer in the struggle for existence, and to increase at
his expense, just as the better adapted, increase at the
expense of the less adapted varieties in the animal and
vegetable kingdoms,— just as the weeds of Europe
overrun North America and Australia, extinguishing
native productions by the inherent vigour of their
organization, and by their greater capacity for existence
and multiplication.

The Origin of the Races of Man.

If these views are correct ; if in proportion as
man's social, moral, and intellectual faculties became
developed, his physical structure would cease to be
affected by the operation of " natural selection," we
have a most important clue to the origin of races.
For it will follow, that those great modifications of
structure and of external form, which resulted in the

320 THE ACTION OF NATURAL

development of man out of some lower type of animal,
must have occurred before his intellect had raised him
above the condition of the brutes, at a period when he
was gregarious, but scarcely social, with a mind per-
ceptive but not reflective, ere any sense of right or
feelings of sympathy had been developed in him. He
would be still subject, like the rest of the organic
world, to the action of 6t natural selection," which
would retain his physical form and constitution in har-
mony with the surrounding universe. He was pro-
bably at a very early period a dominant race, spreading
widely over the warmer regions of the earth as it then
existed, and in agreement with what we see in the
case of other dominant species, gradually becoming
modified in accordance with local conditions. As he
ranged farther from his original home, and became
exposed to greater extremes of climate, to greater
changes of food, and had to contend with new enemies,
organic and inorganic, slight useful variations in his
constitution would be selected and rendered permanent,
and would, on the principle of a correlation of growth,"
be accompanied by corresponding external physical
changes. Thus might have arisen those striking char-
acteristics and special modifications which still distin-
guish the chief races of mankind. The red, black,
yellow, or blushing white skin ; the straight, the curly,
the woolly hair ; the scanty or abundant beard ; the
straight or oblique eyes; the various forms of the
pelvis, the cranium, and other parts of the skeleton.
But while these changes had been going on, his

SELECTION ON MAN. 321

mental development had, from some unknown cause,
greatly advanced, and had now reached that condition
in which it began powerfully to influence his whole
existence, and would therefore become subject to the
irresistible action of " natural selection." This action
would quickly give the ascendency to mind : speech
would probably now be first developed, leading to a
still further advance of the mental faculties ; and from
that moment man, as regards the form and structure of
most parts of his body, would remain almost station-
ary. The art of making weapons, division of labour,
anticipation of the future, restraint of the appetites,
moral, social, and sympathetic feelings, would now
have a preponderating influence on his well being,
and would therefore be that part of his nature on
which " natural selection " would most powerfully act;
and we should thus have explained that wonderful per-
sistence of mere physical characteristics, which is the
stumbling-block of those who advocate the unity of
mankind.

We are now, therefore, enabled to harmonise the
conflicting views of anthropologists on this subject.
Man may have been, indeed I believe must have been,
once a homogeneous race ; but it was at a period of
which we have as yet discovered 110 remains, at a period
so remote in his history, that he had not yet acquired
that wonderfully developed brain, the organ of the
mind, which now, even in his lowest examples, raises
him far above the highest brutes ; — at a period when
he had the form but hardly the nature of man, when

Y

322 THE ACTION OF NAIUEAL

he neither possessed human speech, nor those sympa-
thetic and moral feelings which in a greater or less
degree everywhere now distinguish the race. Just in
proportion as these truly human faculties became deve-
loped in him, would his physical features become fixed
and permanent, because the latter would be of less im-
portance to his well being ; he would be kept in har-
mony with the slowly changing universe around him,
by an advance in mind, rather than by a change in
body. If, therefore, we are of opinion that he was not
really man till these higher faculties were fully deve-
loped, we may fairly assert that there were many ori-
ginally distinct races of men ; while, if we think that
a being closely resembling us in form and structure,
but with mental faculties scarcely raised above the
brute, must still be considered to have been human,
we are fully entitled to maintain the common origin of
all mankind.

The Bearing of these Views on the Antiquity of
Man.

These considerations, it will be seen, enable us to
place the origin of man at a much more remote geo-
logical epoch than has yet been thought possible. He
may even have lived in the Miocene or Eocene period,
when not a single mammal was identical in form with
any existing species. For, in the long series of ages
during which these primeval animals were being slowly
changed into the species which now inhabit the earth,
the power which acted to modify them would only

SELECTION ON MAN. 323

affect the mental organization of man. His brain
alone would have increased in size and complexity, and
his cranium have undergone corresponding changes of
form, while the whole structure of lower animals was
being changed. This will enable us to understand how
the fossil crania of Denise and Engis agree so closely
with existing forms, although they undoubtedly existed
in company with large mammalia now extinct. The
Neanderthal skull may be a specimen of one of the
lowest races then existing, just as the Australians are
the lowest of our modern epoch. We have no reason
to suppose that mind and brain and skull modification,
could go on quicker than that of the other parts of the
organization ; and we must therefore look back very far
in the past, to find man in that early condition in which
his mind was not sufficiently developed, to remove his
body from the modifying influence of external condi-
tions and the cumulative action of " natural selection."
I believe, therefore, that there is no a priori reason
against our finding the remains of man or his works
in the tertiary deposits. The absence of all such
remains in the European beds of this age has little
weight, because, as we go further back in time, it is
natural to suppose that man's distribution over the
surface of the earth was less universal than at present.
Besides, Europe was in a great measure submerged
during the tertiary epoch ; and though its scattered
islands may have been uninhabited by man, it by no
means follows that he did not at the same time exist in
warm or tropical continents. If geologists can point

Y 2

324 THE ACTION OF NATURAL

out to us the most extensive land in the warmer regions
of the earth, which has not been submerged since
Eocene or Miocene times, it is there that we may ex-
pect to find some traces of the very early progenitors of
man. It is there that we may trace back the gradually
decreasing brain of former races, till we come to a time
when the body also begins materially to differ. Then
we shall have reached the starting point of the human
family. Before that period, he had not mind enough
to preserve his body from change, and would, there-
fore, have been subject to the same comparatively rapid
modifications of form as the other mammalia.

Their Bearing on the Dignity and Supremacy of Man.

If the views I have here endeavoured to sustain
have any foundation, they give us a new argument for
placing man apart, as not only the head and culmi-
nating point of the grand series of organic nature, but
as in some degree a new and distinct order of being.
From those infinitely remote ages, when the first rudi-
ments of organic life appeared upon the earth, every
plant, and every animal has been subject to one great
law of physical change. As the earth has gone through
its grand cycles of geological, climatal, and organic
progress, every form of life has been subject to its
irresistible action, and has been continually, but imper-
ceptibly moulded into such new shapes as would pre-
serve their harmony with the ever-changing universe.
No living thing could escape this law of its being ;
none (except, perhaps, the simplest and most rudi-

SELECTION ON MAN. 325

mentary organisms), could remain unchanged and live,
amid the universal change around it.

At length, however, there came into existence a
being in whom that subtle force we term mind, be-
came of greater importance than his mere bodily struc-
ture. Though with a naked and unprotected body,
this gave him clothing against the varying inclemen-
cies of the seasons. Though unable to compete with
the deer in swiftness, or with the wild bull in strength,
this gave him weapons with which to capture or over-
come both. Though less capable than most other ani-
mals of living on the herbs and the fruits that unaided
nature supplies, this wonderful faculty taught him to
govern and direct nature to his own benefit, and make
her produce food for him, when and where he pleased.
From the moment when the first skin was used as
a covering, when the first rude spear was formed to
assist in the chase, when fire was first used to cook his
food, when the first seed was sown or shoot planted,
a grand revolution was effected in nature, a revolu-
tion which in all the previous ages of the earth's his-
tory had had no parallel, for a being had arisen who
was no longer necessarily subject to change with the
changing universe — a being who was in some degree
superior to nature, inasmuch as he knew how to con-
trol and regulate her action, and could keep himself
in harmony with her, not by a change in body, but
by an advance of mind.

Here, then, we see the true grandeur and dignity
of man. On this view of his special attributes, we

326 THE ACTION OF NATURAL

may admit, that even those who claim for him a
position as an order, a class, or a sub-kingdom by
himself, have some show of reason on their side. He
is, indeed, a being apart, since he is not influenced
by the great laws which irresistibly modify all other
organic beings, $"ay more ; this victory which he has
gained for himself, gives him a directing influence
over other existences. Man has not only escaped
" natural selection " himself, but he is actually able
to take away some of that power from nature which
before his appearance she universally exercised. We
can anticipate the time when the earth will produce
only cultivated plants and domestic animals ; when
man's selection shall have supplanted "natural selec-
tion ;" and when the ocean will be the only domain
in which that power can be exerted, which for count-
less cycles of ages ruled supreme over all the earth.

Their Bearing on the future Development of Man.

We now find ourselves enabled to answer those who
maintain, that if Mr. Darwin's theory of the Origin of
Species is true, man too must change in form, and be-
come developed into some other animal as different from
his present self as he is from the Gorilla or the Chim-
panzee ; and who speculate on what this form is likely
to be. But it is evident that such will not be the case ;
for no change of conditions is conceivable, which will
render any important alteration of his form and organi-
zation so universally useful and necessary to him, as
to give those possessing it always the best chance of

SELECTION ON MAN. 327

surviving, and thus lead to the development of a new
species, genus, or higher group of man. On the other
hand, we know that far greater changes of conditions
and of his entire environment have been undergone by
man, than any other highly organized animal could
survive unchanged, and have been]'met by mental, not
corporeal adaptation. The difference of habits, of food,
clothing, weapons, and enemies, between savage and
civilized man, is enormous. Difference in bodily form
and structure there is practically none, except a slightly
increased size of brain, corresponding to his higher
mental development.

We have every reason to believe, then, that man
may have existed and may continue to exist, through
a series of geological periods which shall see all other
forms of animal life again and again changed ; while he
himself remains unchanged, except in the two parti-
culars already specified — the head and face, as imme-
diately connected with the organ of the mind and as
being the medium of expressing the most refined emo-
tions of his nature, — and to a slight extent in colour,
hair, and proportions, so far as they are correlated with
constitutional resistance to disease.

Summary.

Briefly to recapitulate the argument ; — in two dis-
tinct ways has man escaped the influence of those
laws which have produced unceasing change in the
animal world. 1. By his superior intellect he is ena-
bled to provide himself with clothing and weapons, and

328 THE ACTION OF NATURAL

by cultivating the soil to obtain a constant supply of
congenial food. This renders it unnecessary for his
body, like those of the lower animals, to be modified
in accordance Avith changing conditions — to gain a
warmer natural covering, to acquire more powerful
teeth or claws, or to become adapted to obtain and
digest new kinds of food, as circumstances may re-
quire. 2. By his superior sympathetic and moral
feelings, he becomes fitted for the social state ; he
ceases to plunder the weak and helpless of his tribe ;
he shares the game which he has caught with less
active or less fortunate hunters, or exchanges it for
weapons which even the weak or the deformed can
fashion ; he saves the sick and wounded from death ;
and thus the power which leads to the rigid destruc-
tion of all animals who cannot in .every respect help
themselves, is prevented from acting on him.

This power is "natural selection;" and, as by no
other means can it be shown, that individual varia-
tions can ever become accumulated and rendered per-
manent so as to form well-marked races, it follows
that the differences which now separate mankind from
other animals, must have been produced before he be-
came possessed of a human intellect or human sympa-
thies. This view also renders possible, or even requires,
the existence of man at a comparatively remote geo-
logical epoch. For, during the long periods in which
other animals have been undergoing modification in
their whole structure, to such an amount as to con-
stitute distinct genera and families, man's body will

SELECTION ON MAN. 329

have remained generically, or even specifically, the
same, while his head and brain alone will have un-
dergone modification equal to theirs. We can thus
understand how it is that, judging from the head
and brain, Professor Owen places man in a distinct
sub -class of mammalia, while as regards the bony
structure of his body, there is the closest anatomical
resemblance to the anthropoid apes, " every tooth, every
bone, strictly homologous — which makes the determi-
nation of the difference between Homo and Pithecus
the anatomist's difficulty." The present theory fully
recognises and accounts for these facts ; and we may
perhaps claim as corroborative of its truth, that it
neither requires us to depreciate the intellectual chasm
which separates man from the apes, nor refuses full
recognition of the striking resemblances to them, which
exist in other parts of his structure.

Conclusion.

In concluding this brief sketch of a great subject,
I would point out its bearing upon the future of the
human race. If my conclusions are just, it must in-
evitably follow that the higher — the more intellectual
and moral — must displace the lower and more de-
graded races ; and the power of " natural selection,"
still acting on his mental organization, must ever lead
to the more perfect adaptation of man's higher facul-
ties to the conditions of surrounding nature, and to
the exigencies of the social state. While his external
form will probably ever remain unchanged, except in

330 THE ACTION OF NATURAL

the development of that perfect beauty which results
from a healthy and well organized body, refined and
ennobled by the highest intellectual faculties and sym-
pathetic emotions, his mental constitution may con-
tinue to advance and improve, till the world is again
inhabited by a single nearly homogeneous race, no
individual of which will be inferior to the noblest
specimens of existing humanity.

Our progress towards such a result is very slow, but
it still seems to be a progress. We are just now living
at an abnormal period of the world's history, owing to
the marvellous developments and vast practical results
of science, having been given to societies too low
morally and intellectually, to know how to make the
best use of them, and to whom they have consequently
been curses as well as blessings. Among civilized na-
tions at the present day, it does not seem possible for
natural selection to act in any way, so as to secure the
permanent advancement of morality and intelligence ;
for it is indisputably the mediocre, if not the low, both
as regards morality and intelligence, who succeed best
in life and multiply fastest. Yet there is undoubtedly
an advance — on the whole a steady and a permanent
one — both in the influence on public opinion of a high
morality, and in the general desire for intellectual ele-
vation ; and as I cannot impute this in any way to
"survival of the fittest," I am forced to conclude that
it is due, to the inherent progressive power of those
glorious qualities which raise us so immeasurably above
our fellow animals, and at the same time afford us the

SELECTION ON MAX. 331

surest proof that there are other and higher existences
than ourselves, from whom these qualities may have
been derived, and towards whom we may be ever
tending.

332

X.

THE LIMITS OF NATURAL SELECTION AS
APPLIED TO MAN.

THROUGHOUT this volume I have endeavoured to show,
that the known laws of variation, multiplication, and
heredity, resulting in a "struggle for existence" and
the " survival of the fittest," have probably sufficed to
produce all the varieties of structure, all the wonderful
adaptations, all the beauty of form and of colour, that
we see in the animal and vegetable kingdoms. To the
best of my ability I have answered the most obvious
and the most often repeated objections to this theory,
and have, I hope, added to its general strength, by
showing how colour — one of the strongholds of the
advocates of special creation — may be, in almost all its
modifications, accounted for by the combined influence
of sexual selection and the need of protection. I have
also endeavoured to show, how the same power which
has modified animals has acted on man; and have, I
believe, proved that, as soon as the human intellect
became developed above a certain low stage, man's
body would cease to be materially affected by natural
selection, because the development of his mental facul-
ties would render important modifications of its form
and structure unnecessary. It will, therefore, probably

THE LIMITS OF NATURAL SELECTION, ETC. 333

excite some surprise among my readers, to find that
I do not consider that all nature can be explained on
the principles of which I am so ardent an advocate ;
and that I am now myself going to state objections,
and to place limits, to the power of " natural selection."
I believe, however, that there are such limits ; and that
just as surely as we can trace the action of natural
laws in the development of organic forms, and can
clearly conceive that fuller knowledge would enable
us to follow step by step the whole process of that
development, so surely can we trace the action of
some unknown higher law, beyond and independent
of all those laws of which we have any knowledge.
We can trace this action more or less distinctly in
many phenomena, the two most important of which
are — the origin of sensation or consciousness, and the
development of man from the lower animals. I shall
first consider the latter difficulty as more immediately
connected with the subjects discussed in this volume.

What Natural Selection can Not do.

In considering the question of the development of
man by known natural laws, we must ever bear in
mind the first principle of " natural selection," no less
than of the general theory of evolution, that all changes
of form or structure, all increase in the size of an
organ or in its complexity, all greater specialization or
physiological division of labour, can only be brought
about, in as much as it is for the good of the being
so modified. Mr. Darwin himself has taken care to

334 THE LIMIIS OF NATUEAL SELECTION

impress upon us, that "natural selection" has no power
to produce absolute perfection but only relative perfec-
tion, no power to advance any being much beyond
his fellow beings, but only just so much beyond them
as to enable it to survive them in the struggle for
existence. Still less has it any power to produce
modifications which are in any degree injurious to its
possessor, and Mr. Darwin frequently uses the strong
expression, that a single case of this kind would be
fatal to his theory. If, therefore, we find in man any
characters, which all the evidence we can obtain goes
to show would have been actually injurious to him on
their first appearance, they could not possibly have
been produced by natural selection. ' Neither could
any specially developed organ have been so produced
if it had been merely useless to him, or if its use were
not proportionate to its degree of development. Such
cases as these would prove, that some other law, or
some other power, than " natural selection " had been
at work. But if, further, we could see that these
very modifications, though hurtful or useless at the
time when they first appeared, became in the highest
degree useful at a much later period, and are now
essential to the full moral and intellectual development
of human nature, we should then infer the action of
mind, foreseeing the future and preparing for it, just
as surely as we do, when we see the breeder set himself
to work with the determination to produce a definite
improvement in some cultivated plant or domestic
animal. I would further remark that this enquiry is

AS APPLIED TO MAN. 335

as thoroughly scientific and legitimate as that into the
origin of species itself. It is an attempt to solve the
inverse problem, to deduce the existence of a new
power of a definite character, in order to account for
facts which according to the theory of natural selection
ought not to happen. Such problems are well known
to science, and the search after their solution has often
led to the most brilliant results. In the case of man,
there are facts of the nature above alluded to, and in
calling attention to them, and in inferring a cause for
them, I believe that I am as strictly within the bounds
of scientific investigation as I have been in any other
portion of my work.

The Brain of the Savage shoivn to be Larger than he
Needs it to be.

Size of Brain an important Element of Mental
Power. — The brain is universally admitted to be the
organ of the mind ; and it is almost as universally
admitted, that size of brain is one of the most impor-
tant of the elements which determine mental power
or capacity. There seems to be no doubt that brains
differ considerably in quality, as indicated by greater
or less complexity of the convolutions, quantity of grey
matter, and perhaps unknown peculiarities of organiza-
tion ; but this difference of quality seems merely to
increase or diminish the influence of quantity, not to
neutralize it. Thus, all the most eminent modern
writers see an intimate connection between the di-
minished size of the brain in the lower races of man-

336 THE LIMITS OF NATURAL SELECTION

kind, and their intellectual inferiority. The collections
of Dr. J. B. Davis and Dr. Morton give the following
as the average internal capacity of the cranium in the
chief races : — Teutonic family, 94 cubic inches ; Esqui-
maux, 91 cubic inches ; Negroes, 85 cubic inches ;
Australians and Tasmanians, 82 cubic inches; Bush-
men, 77 cubic inches. These last numbers, however,
are deduced from comparatively few specimens, and
may be below the average, just as a small number of
Finns and Cossacks give 98 cubic inches, or con-
siderably more than that of the German races. It is
evident, therefore, that the absolute bulk of the brain
is not necessarily much less in savage than in civilised
man, for Esquimaux skulls are known with a capacity
of 113 inches, or hardly less than the largest among
Europeans. But what is still more extraordinary, the
few remains yet known of pre-historic man do not
indicate any material diminution in the size of the
brain case. A Swiss skull of the stone age, found
in the lake dwelling of Meilen, corresponded exactly
to that of a Swiss youth of the present day. The
celebrated Neanderthal skull had a larger circumfer-
ence than the average, and its capacity, indicating
actual mass of brain, is estimated to have been not less
than 75 cubic inches, or nearly the average of exist-
ing Australian crania. The Engis skull, perhaps the
oldest known, and which, according to Sir John
Lubbock, a there seems no doubt was really contem-
porary with the mammoth and the cave bear," is yet,
according to Professor Huxley, "a fair average skull,

AS APPLIED TO MAN. 337

which might have belonged to a philosopher, or might
have contained the thoughtless brains of a savage. "

" O

Of the cave men of Les Eyzies, who were undoubtedly
contemporary with the reindeer in the South of France,
Professor Paul Broca says (in a paper read before
the Congress of Pre-historic Archaeology in 1868) —
" The great capacity of the brain, the development of
the frontal region, the fine elliptical form of the anterior
part of the profile of the skull, are incontestible char-
acteristics of superiority, such as we are accustomed to
meet with in civilised races ; " yet the great breadth of
the face, the enormous development of the ascending
ramus of the lower jaw, the extent and roughness of
the surfaces for the attachment of the muscles, espe-
cially of the masticators, and the extraordinary de-
velopment of the ridge of the femur, indicate enormous
muscular power, and the habits of a savage and
brutal race.

These facts might almost make us doubt whether
the size of the brain is in any direct way an index of
mental power, had we not the most conclusive evidence
that it is so, in the fact that, whenever an adult male
European has a skull less than nineteen inches in cir-
cumference, or has less than sixty-five cubic inches of
brain, he is invariably idiotic. When we join with this
the equally undisputed fact, that great men — those who
combine acute perception with great reflective power,
strong passions, and general energy of character, such
as Napoleon, Cuvier, and O'Connell, have always heads
far above the average size, we must feel satisfied that

z

338 THE LIMITS OF NATURAL SELECTION

volume of brain is one, and perhaps the most impor-
tant, measure of intellect ; and this being the case, we
cannot fail to be struck with the apparent anomaly,
that many of the lowest savages should have as much
brains as average Europeans. The idea is suggested
of a surplusage of power ; of an instrument beyond the
needs of its possessor.

Comparison of the Brains of Man and of Anthropoid
Apes. — In order to discover if there is any foundation
for this notion, let us compare the brain of man with
that of animals. The adult male Orang-utan is quite as
bulky as a small sized man, while the Gorilla is consi-
derably above the average size of man, as estimated by
bulk and weight ; yet the former has a brain of only
28 cubic inches, the latter, one of 30, or, in the largest
specimen yet known, of 34J cubic inches. We have
seen that the average cranial capacity of the lowest
savages is probably not less than Jive-sixths of that of
the highest civilized races, while the brain of the
anthropoid apes scarcely amounts to one-third of that
of man, in both cases taking the average; or the
proportions may be more clearly represented by the
following figures — anthropoid apes, 10 ; savages, 26 ;
civilized man, 32. But do these figures at all approxi-
mately represent the relative intellect of the three
groups ? Is the savage really no further removed from
.the philosopher, and so much removed from the ape,
as these figures would indicate ? In considering this
question, we must not forget that the heads of savages
vary in size, almost as much as those of civilized

AS APPLIED TO MAN. 339

Europeans. Thus, while the largest Teutonic skull
in Dr. Davis' collection is 112'4 cubic inches, there is
an Araucanian of 115*5, an Esquimaux of 113*1, a
Marquesan of 110*6, a Negro of 105*8, and even an
Australian of 104*5 cubic inches. We may, there-
fore, fairly compare the savage with the highest
European on the one side, and with the Orang, Chim-
panzee, or Gorilla, on the other, and see whether
there is any relative proportion between brain and
intellect.

Range of intellectual power in Man. — First, let us
consider what this wonderful instrument, the brain, is
capable of in its higher developments. In Mr. Galton's
interesting work on " Hereditary Genius," he remarks
on the enormous difference between the intellectual
power and grasp of the well-trained mathematician
or man of science, and the average Englishman. The
number of marks obtained by high wranglers, is often
more than thirty times as great as that of the men
at the bottom of the honour list, who are still of fair
mathematical ability ; and it is the opinion of skilled
examiners, that even this does not represent the full
difference of intellectual power. If, now, we descend
to those savage tribes who only count to three or five,
and who find it impossible to comprehend the addition
of two and three without having the objects actually
before them, we feel that the chasm between them and
the good mathematician is so vast, that a thousand to
one will probably not fully express it. Yet we know
that the mass of brain might be nearly the same in

z 2

340 THE LIMITS OF NATURAL SELECTION

both, or might not differ in a greater proportion than
as 5 to 6 ; whence we may fairly infer that the savage
possesses a brain capable, if cultivated and developed,
of performing work of a kind and degree far beyond
what he ever requires it to do.

Again, let us consider the power of the higher or
even the average civilized man, of forming abstract
ideas, and carrying on more or less complex trains
of reasoning. Our languages are full of terms to
express abstract conceptions. Our business and our
pleasures involve the continual foresight of many con-
tingencies. Our law, our government, and our science,
continually require us to reason through a variety of
complicated phenomena to the expected result. Even
our games, such as chess, compel us to exercise all
these faculties in a remarkable degree. Compare this
with the savage languages, which contain no words
for abstract conceptions ; the utter want of foresight
of the savage man beyond his simplest necessities ; his
inability to combine, or to compare, or to reason on
any general subject that does not immediately appeal
to his senses. So, in his moral and aesthetic faculties,
the savage has none of those wide sympathies with all
nature, those conceptions of the infinite, of the good,
of the sublime and beautiful, which are so largely
developed in civilized man. Any considerable develop-
ment of these would, in fact, be useless or even hurtful
to him, since they would to some extent interfere with
the supremacy of those perceptive and animal faculties
on which his very existence often depends, in the

AS APPLIED TO MAX. 341

severe struggle he has to carry on against nature and
his fellow-man. Yet the rudiments of all these powers
and feelings undoubtedly exist in him, since one or
other of them frequently manifest themselves in ex-
ceptional cases, or when some specia.1 circumstances
call them forth. Some tribes, such as the Santals,
are remarkable for as pure a love of truth as the most
moral among civilized men. The Hindoo and the
Polynesian have a high artistic feeling, the first traces
of which are clearly visible in the rude drawings of
the palaeolithic men who were the contemporaries in
France of the Reindeer and the Mammoth. Instances
of unselfish love, of true gratitude, and of deep reli-
gious feeling, sometimes occur among most savage
races.

On the whole, then, we may conclude, that the general
moral and intellectual development of the savage, is
not less removed from that of civilized man than has
been shown to be the case in the one department
of mathematics ; and from the fact that all the moral
and intellectual faculties do occasionally manifest them-
selves, we may fairly conclude that they are always
latent, and that the large brain of the savage man is
much beyond his actual requirements in the savage
state.

Intellect of Savages and of Animals compared. — Let
us now compare the intellectual wants of the savage,
and the actual amount of intellect he exhibits, with
those of the higher animals. Such races as the
Andaman Islanders, the Australians, and the Tasma-

342 THE LIMITS OF NATURAL SELECTION

nians, the Digger Indians of North America, or the
natives of Fuegia, pass their lives so as to require
the exercise of few faculties not possessed in an equal
degree by many animals. In the mode of capture of
game or fish, they by no means surpass the ingenuity
or forethought of the jaguar, who drops saliva into
the water, and seizes the fish as they come to eat it;
or of wolves and jackals, who hunt in packs; or of
the fox, who buries his surplus food till he requires
it. The sentinels placed by antelopes and by monkeys,
and the various modes of building adopted by field
mice and beavers, as well as the sleeping place of the
orang-utan, and the tree-shelter of some of the Afri-
can anthropoid apes, may well be compared with the
amount of care and forethought bestowed by many
savages in similar circumstances. His possession of
free and perfect hands, not required for locomotion,
enable man to form and use weapons and implements
which are beyond the physical powers of brutes ; but
having done this, he certainly does not exhibit more
mind in using them than do many lower animals.
What is there in the life of the savage, but the satisfy-
ing of the cravings of appetite in the simplest and
easiest way ? What thoughts, ideas, or actions are
there, that raise him many grades above the elephant
or the ape ? Yet he possesses, as we have seen, a
brain vastly superior to theirs in size and complexity;
and this brain gives him, in an undeveloped state,
faculties which he never requires to use. And if this
is true of existing savages, how much more true must

AS APPLIED TO MAN. 343

it have been of the men whose sole weapons were
rudely chipped flints, and some of whom, we may
fairly conclude, were lower than any existing race ;
while the only evidence yet in our possession shows
them to have had brains fully as capacious as those
of the average of the lower savage races.

We see, then, that whether we compare the savage
with the higher developments of man, or with the
brutes around him, we are alike driven to the con-
clusion that in his large and well-developed brain
he possesses an organ quite disproportionate to his
actual requirements — an organ that seems prepared in
advance, only to be fully utilized as he progresses in
civilization. A brain slightly larger than that of the
gorilla would, according to the evidence before us,
fully have sufficed for the limited mental development
of the savage; and we must therefore admit, that the
large brain he actually possesses could never have
been solely developed by any of those laws of evolu-
tion, whose essence is, that they lead to a degree of
organization exactly proportionate to the wants of
each species, never beyond those wants — that no pre-
paration can be made for the future development of
the race — that one part of the body can never increase
in size or complexity, except in strict co-ordination to
the pressing wants of the whole. The brain of pre-
historic and of savage man seems to me to prove
the existence of some power, distinct from that which
has guided the development of the lower animals
through their ever- varying forms of being.

344 THE LIMITS OF NATURAL SELECTION

The Use of the Hairy Covering of Mammalia.

Let us now consider another point in man's organi-
zation, the bearing of which has been almost entirely
overlooked by writers on both sides of this question.
One of the most general external characters of the
terrestrial mammalia is the hairy covering of the body,
which, whenever the skin is flexible, soft, and sensitive,
forms a natural protection against the severities of cli-
mate, and particularly against rain. That this is its
most important function, is well shown by the manner
in which the hairs are disposed so as to carry off the
water, by being invariably directed downwards from
the most elevated parts of the body. Thus, on the under
surface the hair is always less plentiful, and, in many
cases, the belly is almost bare. The hair lies down-
wards, on the limbs of all walking mammals, from the
shoulder to the toes, but in the orang-utan it is directed
from the shoulder to the elbow, and again from the
wrist to the elbow, in a reverse direction. This corre-
sponds to the habits of the animal, which, when resting,
holds its long arms upwards over its head, or clasping
a branch above it, so that the rain would flow down
both the arm and fore-arm to the long hair which meets
at the elbow. In accordance with this principle, the
hair is always longer or more dense along the spine
or middle of the back from the nape to the tail, often
rising into a crest of hair or bristles on the ridge of the
back. This character prevails through the entire series
of the mammalia, from the marsupials to the quadru-

AS APPLIED TO MAN. 345

mana, and by this long persistence it must have ac-
quired such a powerful hereditary tendency, that we
should expect it to reappear continually even after it
had been abolished by ages of the most rigid selection ;
and we may feel sure that it never could have been
completely abolished under the law of natural selec-
tion, unless it had become so positively injurious as to
lead to the almost invariable extinction of individuals
possessing it.

The constant absence of Hair from certain parts of
Man's Body a remarkable Phenomenon.

In man the hairy covering of the body has almost
totally disappeared, and, what is very remarkable, it
has disappeared more completely from the back than
from any other part of the body. Bearded and beard-
less races alike have the back smooth, and even when
a considerable quantity of hair appears on the limbs
and breast, the back, and especially the spinal region,
is absolutely free, thus completely reversing the charac-
teristics of all other mammalia. The Ainos of the Kurile
Islands and Japan are said to be a hairy race ; but Mr.
Bickmore, who saw some of them, and described them
in a paper read before the Ethnological Society, gives
no details as to where the hair was most abundant,
merely stating generally, that " their chief peculiarity
is their great abundance of hair, not only on the head
and face, but over the whole body." This might very
well be said of any man who had hairy limbs and
breast, unless it was specially stated that his back was

346 THE LIMITS OF NATURAL SELECTION

hairy, which is not clone in this case. The hairy family
in Birmah have, indeed, hair on the back rather longer
than on the breast, thus reproducing the true mam-
malian character, but they have still longer hair on the
face, forehead, and inside the ears, which is quite ab-
normal ; and the fact that their teeth are all very im-
perfect, shows that this is a case of monstrosity rather
than one of true reversion to the ancestral type of man
before he lost his hairy covering.

Savage Man feels the Want of this Hairy Covering.

We must now enquire if we have any evidence to
show, or any reason to believe, that a hairy covering to
the back would be in any degree hurtful to savage
man, or to man in any stage of his progress from his
lower animal form ; and if it were merely useless, could
it have been so entirely and completely removed as not
to be continually reappearing in mixed races ? Let
us look to savage man for some light on these points.
One of the most common habits of savages is to use
some covering for the back and shoulders, even when
they have none on any other part of the body. The
early voyagers observed with surprise, that the Tas-
manians, both men and women, wore the kangaroo-
skin, which was their only covering, not from any
feeling of modesty, but over the shoulders to keep the
back dry and warm. A cloth over the shoulders was
also the national dress of the Maories. The Patago-
nians wear a cloak or mantle over the shoulders, and
the Fuegians often wear a small piece of skin on the

AS APPLIED TO MAN. 347

back, laced on. and shifted from side to side as the
wind blows. The Hottentots also wore a somewhat
similar skin over the back, which they never removed,
and in which they were buried. Even in the tropics
most savages take precautions to keep their backs dry.
The natives of Timor use the leaf of a fan palm, care-
fully stitched up and folded, which they always carry
with them, and which, held over the back, forms an
admirable protection from the rain. Almost all the
Malay races, as well as the Indians of South America,
make great palm-leaf hats, four feet or more across,
which they use during their canoe voyages to protect
their bodies from heavy showers of rain; and they
use smaller hats of the same kind when travelling
by land.

"We find, then, that so far from there being any
reason to believe that a hairy covering to the back
could have been hurtful or even useless to pre-historic
man, the habits of modern savages indicate exactly the
opposite view, as they evidently feel the want of it, and
are obliged to provide substitutes of various kinds.
The perfectly erect posture of man, may be supposed to
have something to do with the disappearance of the
hair from his body, while it remains on his head ; but
when walking, exposed to rain and wind, a man natur-
ally stoops forwards, and thus exposes his back ; and the
undoubted fact, that most savages'feel the effects of cold
and wet most severely in that part of the body, suffi-
ciently demonstrates that the hair could not have ceased
to grow there merely because it was useless, even if it

348 THE LIMITS OF NATUEAL SELECTION

were likely that a character so long persistent in the
entire order of mammalia, could have so completely dis-
appeared, under the influence of so weak a selective
power as a diminished usefulness.

Marts Naked Skin could not have been produced by
Natural Selection.

It seems to me, then, to be absolutely certain, that
a Natural Selection " could not have produced man's
hairless body by the accumulation of variations from a
hairy ancestor. The evidence all goes to show that
such variations could not have been useful, but must,
on the contrary, have been to some extent hurtful. If
even, owing to an unknown correlation with other
hurtful qualities, it had been abolished in the ancestral
tropical man, we cannot conceive that, as man spread
into colder climates, it should not have returned under
the powerful influence of reversion to such a long per-
sistent ancestral type. But the very foundation of
such a supposition as this is untenable ; for we cannot
suppose that a character which, like hairiness, exists
throughout the whole of the mammalia, can have be-
come, in one form only, so constantly correlated with
an injurious character, as to lead to its permanent
suppression — a suppression so complete and effectual
that it never, or scarcely ever, reappears in mongrels
of the most widely different races of man.

Two characters could hardly be wider apart, than
the size and development of man's brain, and the dis-
tribution of hair upon the surface of his body ; yet

AS APPLIED TO MAN. 349

they both lead us to the same conclusion — that some
other power than Natural Selection has been engaged
in his production.

Feet and Hands of Man, considered as Difficulties on
the Theory of Natural Selection.

There are a few other physical characteristics of
man, that may just be mentioned as offering similar
difficulties, though I do not attach the same importance
to them as to those I have already dwelt on. The
specialization and perfection of the hands and feet of
man seems difficult to account for. Throughout the
whole of the quadrumana the foot is prehensile ; and a
very rigid selection must therefore have been needed
to bring about that arrangement of the bones and
muscles, which has converted the thumb into a great
toe, so completely, that the power of opposability is
totally lost in every race, whatever some travellers
may vaguely assert to the contrary. It is difficult to
see why the prehensile power should have been taken
away. It must certainly have been useful in climb-
ing, and the case of the baboons shows that it is quite
compatible with terrestrial locomotion. It may not
be compatible with perfectly easy erect locomotion;
but, then, how can we conceive that early man, as an
animal, gained anything by purely erect locomotion ?
Again, the hand of man contains latent capacities
and powers which are unused by savages, and must
have been even less used by palaeolithic man and his
still ruder predecessors. It has all the appearance of

350 THE LIMITS OF NATURAL SELECTION

an organ prepared for the use of civilized man, and
one which was required to render civilization possi-
ble. Apes make little use of their separate fingers
and opposable thumbs. They grasp objects rudely
and clumsily, and look as if a much less specialized
extremity would have served their purpose as well.
I do not lay much stress on this, but, if it be proved
that some intelligent power has guided or determined
the development of man, then we may see indications
of that power, in facts which, by themselves, would
not serve to prove its existence.

Tlie voice of man. — The same remark will apply
to another peculiarly human character, the wonder-
ful power, range, flexibility, and sweetness, of the
musical sounds producible by the human larynx,
especially in the female sex. The habits of savages
give no indication of how this faculty could have
been developed by natural selection; because it is
never required or used by them. The singing of
savages is a more or less monotonous howling, and
the females seldom sing at all. Savages certainly
never choose their wives for fine voices, but for rude
health, and strength, and physical beauty. Sexual
selection could not therefore have developed this won-
derful power, which only comes into play among
civilized people. It seems as if the organ had been
prepared in anticipation of the future progress of man,
since it contains latent capacities which are useless
to him in his earlier condition. The delicate correla-
tions of structure that give it such marvellous powers,

AS APPLIED TO MAN. 351

could not therefore have been acquired by means of
natural selection.

The Origin of some of Man's Mental Faculties, by the
preservation of Useful Variations, not possible.

Turning to the mind of man, we meet with mariy
difficulties in attempting to understand, how those
mental faculties, which are especially human, could
have been acquired by the preservation of useful
variations. At first sight, it would seem that such
feelings as those of abstract justice and benevolence
could never have been so acquired, because they are
incompatible with the law of the strongest, which is
the essence of natural selection. But this is, I think,
an erroneous view, because we must look, not to indi-
viduals but to societies ; and justice and benevolence,
exercised towards members of the same tribe, would
certainly tend to strengthen that tribe, and give it
a superiority over another in which the right of the
strongest prevailed, and where consequently the weak
and the sickly were left to perish, and the few strong
ruthlessly destroyed the many who were weaker.

But there is another class of human faculties that
do not regard our fellow men, and which cannot,
therefore, be thus accounted for. Such are the capa-
city to form ideal conceptions of space and time, of
eternity and infinity — the capacity for intense artistic
feelings of pleasure, in form, colour, and composition —
and for those abstract notions of form and number
which render geometry and arithmetic possible. How

352 THE LIMITS OF NATURAL SELECTION

were all or any of these faculties first developed, when
they could have been of no possible use to man in
his early stages of barbarism ? How could " natural
selection," or survival of the fittest in the struggle
for existence, at all favour the development of mental
powers so entirely removed from the material neces-
sities of savage men, and which even now, with our
comparatively high civilization, are, in their farthest
developments, in advance of the age, and appear to
have relation rather to the future of the race than
to its actual status?

Difficulty as to the Origin of the Moral Sense.

Exactly the same difficulty arises, when we endeavour
to account for the development of the moral sense or
conscience in savage man ; for although the practice of
benevolence, honesty, or truth, may have been useful
to the tribe possessing these virtues, that does not at
all account for the peculiar sanctity, attached to actions
which each tribe considers right and moral, as con-
trasted with the very different feelings with which
they regard what is merely useful. The utilitarian
hypothesis (which is the theory of natural selection
applied to the mind) seems inadequate to account for
the development of the moral sense. This subject has
been recently much discussed, and I will here only
give one example to illustrate my argument. The
utilitarian sanction for truthfulness is by no means
very powerful or universal. Few laws enforce it. ISTo
very severe reprobation follows untruthfulness. In all

AS APPLIED TO MAN. 353

ages and countries, falsehood has been thought allow-
able in love, and laudable in war ; while, at the present
day, it is held to be venial by the majority of mankind,
in trade, commerce, and speculation. A certain amount
of untruthfulness is a necessary part of politeness in
the east and west alike, while even severe moralists
have held a lie justifiable, to elude an enemy or prevent
a crime. Such being the difficulties with which this
virtue has had to struggle, with so many exceptions
to its practice, with so many instances in which it
brought ruin or death to its too ardent devotee, how
can we believe that considerations of utility could
ever invest it with the mysterious sanctity of the
highest virtue, — could ever induce men to value
truth for its own sake, and practice it regardless of
consequences ?

Yet, it is a fact, that such a mystical sense of wrong
does attach to untruthfulness, not only among the
higher classes of civilized people, but among whole
tribes of utter savages. Sir Walter Elliott tells us
(in his paper " On the Characteristics of the Popula-
tion of Central and Southern India," published in
the Journal of the Ethnological Society of London,
vol. i., p. 107) that the Kurubars and Santals, barbar-
ous hill-tribes of Central India, are noted for veracity.
It is a common saying that " a Kurubar always speaks
the truth; " and Major Jervis says, " the Santals are
the most truthful men I ever met with." As a re-
markable instance of this quality the following fact is
given. A number of prisoners, taken during the

2 A

354 THE LIMITS OF NATUEAL SELECTION

Santal insurrection, were allowed to go free on parole,
to work at a certain spot for wages. After some
time cholera attacked them and they were obliged to
leave, but every man of them returned and gave up
his earnings to the guard. Two hundred savages
with money in their girdles, walked thirty miles back
to prison rather than break their word ! My own
experience among savages has furnished me with
similar, although less severely tested, instances; and
we cannot avoid asking, how is it, that in these few
cases " experiences of utility " have left such an over-
whelming impression, while in so many others they
have left none ? The experiences of savage men as
regards the utility of truth, must, in the long run,
be pretty nearly equal. How is it, then, that in some
cases the result is a sanctity which overrides all con-
siderations of personal advantage, while in others there
is hardly a rudiment of such a feeling ?

The intuitional theory, which I am now advocating,
explains this by the supposition, that there is a feeling —
a sense of right and wrong — in our nature, antecedent
to and independent of experiences of utility. Where
free play is allowed to the relations between man and
man, this feeling attaches itself to those acts of uni-
versal utility or self-sacrifice, which are the products
of our affections and sympathies, and which we .term
moral ; while it may be, and often is, perverted, to
give the same sanction to acts of narrow and con-
ventional utility which are really immoral, — as when
the Hindoo will tell a lie, but will sooner starve than

AS APPLIED TO MAN. 355

eat unclean food ; and looks upon the marriage of
adult females as gross immorality.

The strength of the moral feeling will depend upon
individual or racial constitution, and on education
and habit; — the acts to which its sanctions are applied,
will depend upon how far the simple feelings and affec-
tions of our nature, have been modified by custom,
by law, or by religion.

It is difficult to conceive that such an intense and
mystical feeling of right and wrong, (so intense as
to overcome all ideas of personal advantage or utility),
could have been developed out of accumulated ancestral
experiences of utility ; and still more difficult to under-
stand, how feelings developed by one set of utilities,
could be transferred to acts of which the utility was
partial, imaginary, or altogether absent. But if a
moral sense is an essential part of our nature, it is
easy to see, that its sanction may often be given to
acts which are useless or immoral ; just as the natural
appetite for drink, is perverted by the drunkard into
the means of his destruction.

Summary of the Argument as to the Insufficiency of
Natural Selection to account for the Development of
Man.

Briefly to resume my argument — I have shown that
the brain of the lowest savages, and, as far as we yet
know, of the pre-historic races, is little inferior in size
to that of the highest types of man, and immensely
superior to that of the higher animals ; while it is.

2 A 2

356 THE LIMITS OF NATURAL SELECTION

universally admitted that quantity of brain is one of
the most important, and probably the most essential, of
the elements which determine mental power. Yet the
mental requirements of savages, and the faculties ac-
tually exercised by them, are very little above those of
animals. The higher feelings of pure morality and re-
fined emotion, and the power of abstract reasoning and
ideal conception, are useless to them, are rarely if ever
manifested, and have no important relations to their
habits, wants, desires, or well-being. They possess a
mental organ beyond their needs. Natural Selection
could only have endowed savage man with a brain a
little superior to that of an ape, whereas he actually
possesses one very little inferior to that of a philo-
sopher.

The soft, naked, sensitive skin of man, entirely free
from that hairy covering which is so universal among
other mammalia, cannot be explained on the theory of
natural selection. The habits of savages show that
they feel the want of this covering, which is most com-
pletely absent in man exactly where it is thickest in
other animals. We have no reason whatever to be-
lieve, that it could have been hurtful, or even useless to
primitive man ; and, under these circumstances, its com-
plete abolition, shown by its never reverting in mixed
breeds, is a demonstration of the agency of some other
power than the law of the survival of the fittest, in the
development of man from the lower animals.

Other characters show difficulties of a similar kind,
though not perhaps in an equal degree. The structure

AS APPLIED TO MAN. 357

of the human foot and hand seem unnecessarily perfect
for the needs of savage man, in whom they are as
completely and as humanly developed as in the highest
races. The structure of the human larynx, giving the
power of speech and of producing musical sounds, and
especially its extreme development in the female sex,
are shown to be beyond the needs of savages, and from
their known habits, impossible to have been acquired
either by sexual selection, or by survival of the fittest.

The mind of man offers arguments in the same direc-
tion, hardly less strong than those derived from his
bodily structure. A number of his mental faculties
have no relation to his fellow men, or to his material
progress. The power of conceiving eternity and in-
finity, and all those purely abstract notions of form,
number, and harmony, which play so large a part in
the life of civilised races, are entirely outside of the
world of thought of the savage, and have no influence
on his individual existence or on that of his tribe.
They could not, therefore, have been developed by any
preservation of useful forms of thought ; yet we find
occasional traces of them amidst a low civilization, and
at a time when they could have had no practical effect
on the success of the individual, the family, or the
race ; and the development of a moral sense or con-
science by similar means is equally inconceivable.

But, on the other hand, we find that every one of
these characteristics is necessary for the full develop-
ment of human nature. The rapid progress of civi-
lization under favourable conditions, would not be

358 THE LIMITS OF NATUEAL SELECTION

possible, were not the organ of the mind of man pre-
pared in advance, fully developed as regards size,
structure, and proportions, and only needing a few
generations of use and habit to co-ordinate its com-
plex functions. The] naked and sensitive skin, by
necessitating clothing and houses, would lead to the
more rapid development of man's inventive and con-
structive faculties ; and, by leading to a more refined
feeling of personal modesty, may have influenced, to a
considerable extent, his moral nature. The erect form
of man, by freeing the hands from all locomptive uses,
has been necessary for his intellectual advancement;
and the extreme perfection of his hands, has alone
rendered possible that excellence in all the arts of civili-
zation which raises him so far above the savage, and
is perhaps but the forerunner of a higher intellectual
and moral advancement. The perfection of his vocal
organs has first led to the formation of articulate
speech, and then to the development of those exqui-
sitely toned sounds, which are only appreciated by the
higher races, and which are probably destined for more
elevated uses and more refined enjoyment, in a higher
condition than we have yet attained to. So, those
faculties which enable us to transcend time and space,
and to realize the wonderful conceptions of mathe-
matics and philosophy, or which give us an intense
yearning for abstract truth, (all of which were occasion-
ally manifested at such an early period of human his-
tory as to be far in advance of any of the few practical
applications which have since grown out of them), are-

AS APPLIED TO MAN. 359

evidently essential to the perfect development of man
as a spiritual being, but are utterly inconceivable as
having been produced through the action of a law
which looks only, and can look only, to the immediate
material welfare of the individual or the race.

The inference I would draw from this class of phe-
nomena is, that a superior intelligence has guided the
development of man in a definite direction, and for a
special purpose, just as man guides the development of
many animal and vegetable forms. The laws of evolu-
tion alone would, perhaps, never have produced a grain
so well adapted to man's use as wheat and maize ; such
fruits as the seedless banana and bread-fruit ; or such
animals as the Guernsey milch cow, or the London
dray-horse. Yet these so closely resemble the unaided
productions of nature, that we may well imagine a
being who had mastered the laws of development of or-
ganic forms through past ages, refusing to believe that
any new power had been concerned in their produc-
tion, and scornfully rejecting the theory (as my theory
will be rejected by many who agree with me on other
points), that in these few cases a ^controlling intelli-
gence had directed the action of the laws of variation,
multiplication, and survival, for his own purposes. "We
know, however, that this has been done ; and we must
therefore admit the possibility that, if we are not the
highest intelligences in the universe, some higher intel-
ligence may have directed the process by which the
human race was developed, by means of more subtle
agencies than we are acquainted with. At the same

360 THE LIMITS OF NATURAL SELECTION

time I must confess, that this theory has the disadvan-
tage of requiring the intervention of some distinct indi-
vidual intelligence, to aid in the production of what we
can hardly avoid considering as the ultimate aim and
outcome of all organized existence — intellectual, ever-
advancing, spiritual man. It therefore implies, that
the great laws which govern the material universe were
insufficient for his production, unless we consider (as
we may fairly do) that the controlling action of such
higher intelligences is a necessary part of those laws,
just as the action of all surrounding organisms is one of
the agencies in organic development. But even if my
particular view should not be the true one, the difficul-
ties I have put forward remain, and I think prove, that
some more general and more fundamental law under-
lies that of " natural selection." The law of u uncon-
scious intelligence" pervading all organic nature, put
forth by Dr. Laycock and adopted by Mr. Murphy, is
such a law ; but to my mind it has the double disad-
vantage of being both unintelligible and incapable of
any kind of proof. It is more probable, that the true
law lies too deep for us to discover it ; but there seems
to me, to be ample indications that such a law does
exist, and is probably connected with the absolute ori-
gin of life and organization.

TJie Origin of Consciousness.

The question of the origin of sensation and of thought
can be but briefly discussed in this place, since it is a
subject wide enough to require a separate volume for

AS APPLIED TO MAX. 361

its proper treatment. No physiologist or philosopher
has yet ventured to propound an intelligible theory, of
how sensation may possibly be a product of organiza-
tion ; while many have declared the passage from mat-
ter to mind to be inconceivable. In his presidential
address to the Physical Section of the British Associa-
tion at Norwich, in 1868, Professor Tyndall expressed
himself as follows : —

" The passage from the physics of the brain to the
corresponding facts of consciousness is unthinkable.
Granted that a definite thought, and a definite mole-
cular action in the brain occur simultaneously, we do
not possess the intellectual organ, nor apparently any
rudiment of the organ, which would enable us to pass
by a process of reasoning from the one phenomenon
to the other. They appear together, but we do not
know why. Were our minds and senses so expanded,
strengthened, and illuminated as to enable us to see and
feel the very molecules of the brain ; were we capable
of following all their motions, all their groupings, all
their electric discharges, if such there be, and were we
intimately acquainted with the corresponding states of
thought and feeling, we should be as far as ever from
the solution of the problem, ' How are these physical
processes connected with the facts of consciousness ? '
The chasm between the two classes of phenomena would
still remain intellectually impassable."

In his latest work (" An Introduction to the Classifica-
tion of Animals,") published in 1859, Professor Huxley
unhesitatingly adopts the "well founded doctrine, that

362 THE LIMITS OF NATUEAL SELECTION

life is the cause and not the consequence of organiza-
tion." In his celebrated article " On the Physical
Basis of Life," however, he maintains, that life is a
property of protoplasm, and that protoplasm owes its
properties to the nature and disposition of its molecules.
Hence he terms it " the matter of life," and believes
that all the physical properties of organized beings are
due to the physical properties of protoplasm. So far
we might, perhaps, follow him, but he does not stop
here. He proceeds to bridge over that chasm which
Professor Tyndall has declared to be " intellectually
impassable," and, by means which he states to be
logical, arrives at the conclusion, that our " thoughts
are the expression of molecular changes in -that matter
of life which is the source of our other vital phenomena."
Not having been able to find any clue in Professor
Huxley's writings, to the steps by which he p'asses from
those vital phenomena, which consist only, in their
last analysis, of movements of particles of matter, to
those other phenomena which we term thought,, sensa-
tion, or consciousness ; but, knowing that so positive an
expression of opinion from him will have great weight
with many persons, I shall endeavour to show, with as
much brevity as is compatible with clearness, that this
theory is not only incapable of proof, but is also, as it
appears to me, inconsistent with accurate conceptions of
molecular physics. To do this, and in order further to
develop my views, I shall have to give a brief sketch
of the most recent speculations and discoveries, as ta
the ultimate nature and constitution of matter.

AS APPLIED TO MAX. 363

The Nature of Matter.

It has been long seen by the best thinkers on the
subject, that atoms, — considered as minute solid bodies
from which emanate the attractive and repulsive forces
which give what we term matter its properties, — could
serve no purpose whatever ; since it is universally
admitted that the supposed atoms never touch each
other, and it cannot be conceived that these homo-
geneous, indivisible, solid units, are themselves the
ultimate cause of the forces that emanate from their
centres. As, therefore, none of the properties of matter
can be due to the atoms themselves, but only to the
forces which emanate from the points in space indi-
cated by the atomic centres, it is logical continually
to diminish their size till they vanish, leaving only
localized 'centres of force to represent them. Of the
various attempts that have been made to show how
.the properties of matter may be due to such modified
atoms (considered as mere centres of force), the most
successful, because the simplest and the most logical, is
that of Mr. Bayma, who, in his "Molecular Mechanics,' *
has demonstrated how, from the simple assumption of
such centres having attractive and repulsive forces
(both varying according to the same law of the in-
verse squares as gravitation), and by grouping them in
symmetrical figures, consisting of a repulsive centre, an
attractive nucleus, and one or more repulsive envelopes,
we may explain all the general properties of matter;
and, by more and more complex arrangements, even

364 THE LIMITS OF NATURAL SELECTION

the special chemical, electrical, and magnetic properties
of special forms of matter.* Each chemical element
will thus consist of a molecule formed of simple atoms,
(or as Mr. Bay ma terms them to avoid confusion,
" material elements") in greater or less number and
of more or less complex arrangement ; which molecule
is in stable equilibrium, but liable to be changed in
form by the attractive or repulsive influences of differ-
ently constituted molecules, constituting the phenomena
of chemical combination, and resulting in new forms
of molecule of greater complexity and more or less
stability.

Those organic compounds of which organized beings
are built up, consist, as is well known, of matter of an
extreme complexity and great instability; whence re-
sult the changes of form to which it is continually
subject. This view enables us to comprehend the possi-
bility, of the phenomena of vegetative life being due to

* Mr. Bayma's work, entitled " The Elements of Molecular
Mechanics," was published in 1866, and has received less
attention than it deserves. It is characterised by great
lucidity, by logical arrangement, and by comparatively simple
geometrical and algebraical demonstrations, so that it may
be understood and appreciated with a very moderate know-
ledge of mathematics. It consists of a series of Propositions,
deduced from the known properties of matter; from these
are derived a number of Theorems, by whose help the more
complicated Problems are solved. Nothing is taken for
granted throughout the work, and the only valid mode of
escaping from its conclusions is, by either disproving the
fundamental Propositions, or by detecting fallacies in the
subsequent reasoning.

AS APPLIED 10 MAN. 365

an almost infinite complexity of molecular combinations,
subject to definite changes under the stimuli of heat,
moisture, light, electricity, and probably some unknown
forces. But this greater and greater complexity, even
if carried to an infinite extent, cannot, of itself, have
the slightest tendency to originate consciousness in such
molecules or groups of molecules. If a material ele-r
ment* or a combination of a thousand material elements
in a molecule, are alike unconscious, it is impossible
for us to believe, that the mere addition of one, two,
or a thousand other material elements to form a more
complex molecule, could in any way tend to produce
a self-conscious existence. The things are radically
distinct. To say that mind is a product or function
of protoplasm, or of its molecular changes, is to use
words to which we can attach no clear conception.
You cannot have, in the whole, what does not exist
in any of the parts ; and those who argue thus should
put forth a definite conception of matter, with clearly
enunciated properties, and show, that the necessary
result of a certain complex arrangement of the ele-
ments or atoms of that matter, will be the production
of self-consciousness. There is no escape from this
dilemma, — either all matter is conscious, or conscious-
ness is something distinct from matter, and in the
latter case, its presence in material forms is a proof
of the existence of conscious beings, outside of, and
independent of, what we term matter.

Matter is force. — The foregoing considerations lead
us to the very important conclusion, that matter is

366 THE LIMITS OF NATURAL SELECTION

essentially force, and nothing but force; that matter,
as popularly understood, does not exist, and is, in fact,
philosophically inconceivable. When we touch matter,
we only really experience sensations of resistance, im-
plying repulsive force; and no other sense can give us
such apparently solid proofs of the reality of matter, as
touch does. This conclusion, if kept constantly present
in the mind, will be found to have a most important
bearing on almost every high scientific and philoso-
phical problem, and especially on such as relate to our
own conscious existence.

All Force is probably Will-Force. — If we are satis-
fied that force or forces are all that exist in the ma-
terial universe, we are next led to enquire what is
force ? We are acquainted with two radically distinct
or apparently distinct kinds of force — the first consists
of the primary forces of nature, such as gravitation,
cohesion, repulsion, heat, electricity, &c. ; the second is
our own will-force. Many persons will at once deny
that the latter exists. It will be said, that it is a mere
transformation of the primary forces before alluded to ;
that the correlation of forces includes those of animal
life, and that will itself is but the result of molecular
change in the brain. I think, however, that it can
be shown, that this latter assertion has neither been
proved, nor even been proved to be possible; and
that in making it, a great leap in the dark has
been taken from the known to the unknown. It
may be at once admitted that the muscular force
of animals and men, is merely the transformed energy

A3 APPLIED TO MAN. 367

derived from the primary forces of nature. So much
has been, if not rigidly proved, yet rendered highly
probable, and it is in perfect accordance with all
our knowledge of natural forces and natural laws.
But it cannot be contended that the physiological
balance-sheet has ever been so accurately struck, that
we are entitled to say, not one-thousandth part of a
grain more of force has been exerted by any organized
body or in any part of it, than has been derived from
the known primary forces of the material world. If
that were so, it would absolutely negative the existence
of will ; for if will is anything, it is a power that directs
the action of the forces stored up in the body, and it
is not conceivable that this direction can take place,
without the exercise of some force in some part of the
organism. However delicately a machine may be con-
structed, with the most exquisitely contrived detents
to release a weight or spring by the exertion of the
smallest possible amount of force, some external force
will always be required ; so, in the animal machine, how-
ever minute may be the changes required in the cells or
fibres of the brain, to set in motion the nerve currents
which loosen or excite the pent up forces of certain
muscles, some force must be required to effect those
changes. If it is said, " those changes are automatic,
and are set in motion by external causes," then one
essential part of our consciousness, a certain amount
of freedom in willing, is annihilated ; and it is incon-
ceivable how or why there should have arisen any
consciousness or any apparent will, in such purely

368 THE LIMITS OF NATURAL SELECTION

automatic organisms. If this were so, our apparent
WILL would be a delusion, and Professor Huxley's be-
lief— " that our volition counts for something as a con-
dition of the course of events," would be fallacious,
since our volition would then be but one link in the
chain of events, counting for neither more nor less
than any other link whatever.

If, therefore, we have traced one force, however mi-
nute, to an origin in our own WILL, while we have no
knowledge of any other primary cause of force, it does
not seem an improbable conclusion that all force may
be will-force ; and thus, that the whole universe, is not
merely dependent on, but actually is, the WILL of higher
intelligences or of one Supreme Intelligence. It has
been often said that the true poet is a seer : and in the
noble verse of an American poetess, we find expressed,
what may prove to be the highest fact of science, the
noblest truth of philosophy :

God of the Granite and the Rose !

Soul of the Sparrow and the Bee !
The mighty tide of Being flows

Through countless channels, Lord, from thee.
It leaps to life in grass and flowers,

Through every grade of being runs,
While from Creation's radiant towers

Its glory flames in Stars and Suns.

Conclusion.

These speculations are usually held to be far beyond
the bounds of science ; but they appear to me to be
more legitimate deductions from the facts of science,

AS APPLIED TO MAN. 361)

than those which consist in reducing the whole universe,
not merely to matter, but to matter conceived and
defined so as to be philosophically inconceivable. It
is surely a great step in advance, to get rid of the
notion that matter is a thing of itself, which can exist
per se, and must have been eternal, since it is supposed
to be indestructible and uncreated, — that force, or the
forces of nature, are another thing, given or added to
matter, or else its necessary properties, — and that
mind is yet another thing, either a product of this
matter and its supposed inherent forces, or distinct
from and co-existent with it ; —and to be able to sub-
stitute for this complicated theory, which leads to
endless dilemmas and contradictions, the far simpler
and more consistent belief, that matter, as an entity
distinct from force, does not exist ; and that FORCE
is a product of MIND. Philosophy had long demon-
strated our incapacity to prove the existence of matter,
as usually conceived ; while it admitted the demon-
stration to each of us of our own self-conscious, ideal
existence. Science has now worked its way up to
the same result, and this agreement between them

' O

should give us some confidence in their combined
teaching.

The view we have now arrived at seems to me
more grand and sublime, as well as far simpler, than
any other. It exhibits the universe, as a universe
of intelligence and will-power ; and by enabling us to
rid ourselves of the impossibility of thinking of mind,
but as connected with our old notions of matter,

2 B

370 THE LIMITS OF NATURAL SELECTION

opens up infinite possibilities of existence, connected
with infinitely varied manifestations of force, totally
distinct from, yet as real as, what we term matter.

The grand law of continuity which we see pervading
our universe, would lead us to infer infinite gradations

/ o

of existence, and to people all space with intelligence
and will-power ; and, if so, we have no difficulty in
believing that for so noble a purpose as the progressive
development of higher and higher intelligences, those
primal and general will-forces, which have sufficed
for the production of the lower animals, should have
been guided into new channels and made to converge
in definite directions. And if, as seems to me probable,
this has been done, I cannot admit that it in any
degree affects the truth or generality of Mr. Darwin's
great discovery. It merely shows, that the laws of
organic development have been occasionally used for
a special end, just as man uses them for his special
ends ; and, I do not see that the law of " natural
selection " can be said to be disproved, if it can be
shown that man does not owe his entire physical and
mental development to its unaided action, any more
than it is disproved by the existence of the poodle
or the pouter pigeon, the production of which may
have been equally beyond its undirected power.

The objections which in this essay 1 have taken, to
the view, — that the same law which appears to have
sufficed for the development of animals, has been alone
the cause of man's superior physical and mental nature,
— will, I have no doubt, be over-ruled and explained

AS APPLIED TO MAN.

371

away. But I venture to think they will nevertheless
maintain their ground, and that they can only be
met by the discovery of new facts or new laws, of
a nature very different from any yet known to us.
I can only hope that my treatment of the subject,
though necessarily very meagre, has been clear and
intelligible ; and that it may prove suggestive, both
to the opponents and to the upholders of the theory
of Natural Selection.

2 B 2

373

INDEX.

AEEAXAS grossulariata, 119.

Acanthotritus dorsalis, 94.

Accipitcr pileatus, 107.

ACR^EID.E, the subjects of mimicry,
85, 86.

Acronycta psi, protective colouring
of, 62.

ADAPTATION brought about by gene-
ral laws, 276 ; looks like design,
281.

^EGERIID.E mimic Hymenoptera,
90.

AGASSIZ, or embryonic character of
ancient animals, 301.

Agnia fasciata, mimics another
Longicorn, 95.

Agriopis aprilina, protective colour-
ing of, 62.

ALCEDINID.E, sexual colouring and
nidification of, 240.

AMADIXA, sexual colouring and ni-
dification of, 243.

AMPELID.E, sexual colouring and
nidification of, 243.

ANCYLOTHERIUM, 300.

ANDRENID.E, 98.

Angr&cum sesquipedule, 272 ; its

fertilization by a large moth,

275.
ANIMALS, senses and faculties of,

127 ; intellect of, compared with

that of savages, 341.
ANISOCERIN.E, 92.
AXOA, 196.

ANOPLOTIIERIUM, 299.

ANTHRIBID.E, mimicry of, 94; di-
morphism in, 155.

Anthrocera filipendulce, 120.

ANTHROPOLOGISTS, wide difference
of opinion among, as to origin
of human races, 304; conflict-
ing views of, harmonized, 321.

ANTIQUITY of man, 303, 322.

APATHUS, 98.

APPARENT exceptions to law of co-
lour and nidification, 253.

AQUATIC birds, why abundant, 32.

Araschnia prorsa, 154.

ARCHEGOSAURUS, 300.

ARCH.EOPTERYX, 300.

ARCHITECTURE of most nations de-
rivative, 228; Grecian, false in
principle, 226.

ARCTIC animals, white colour of,
50, 51.

ARGYLL, Duke of, on colours of
Woodcock, 53 ; on mind in na-
ture, 265; criticism on Darwin's
works, 2G9 ; on humming birds
282; on creation by birth, 287.

ASILUS, 97.

ASPECTS of nature as influencing
man's development, 317.

BABIKUSA, 196.
BALANCE in nature, 42.
BARRINGTON, Hon. Daines, on song
of bird?, 220.

371

1XDEX.

BASILORNIS, 196.

BATES, Mr., first adopted the word
" mimicry," 75 ; his observations
on Leptalis and Heliconidse, 82 ;
his paper explaining the theory
of mimicry, 83 ; objections to
his theory, 108 ; on variation,
165 ; on recent immigration of
Amazonian Indians, 214.

BAYMA, Mr., on "Molecular Me-
chanics," 363, 364.

BEAUTY in nature, 282; not uni-
versal, 284 ; of flowers ucef ul to
them, 285; not given for its own
sake, 285.

BIRDS, possible rapid increase of,
29 ; numbers that die annually,
30 ; mimicry among, 103 ; dull
colour of females, 114; nidi-
fication as affecting colour of
females, 116 ; refusing the
gooseberry caterpillar, 119 ; the
highest in rank and organiza.
tion, 137 ; dimorphism in, 155 ;
why peculiar nest built by each
species, 215-219; build more per-
fect nests as they grow older,
224, 227; alter and improve
their nests, 226; sexual differ-
ences of colour in, 239.

Bombus hortorurn, 90.

Bombjcila garrula, colours and
nidification of, 255.

BOMBYLIUS, 98.

BRAIN of the savage but slightly
less than that of civilized man,
336 ; size of, an important ele-
ment of mental power, 335 ; of
savage races larger than their
needs require, 338, 343 ; of man

and of anthropoid apes com-
pared, 338.

BROCA, Professor Paul, on the fine
crania of the cave men, 337.

Bryophila glandijera and B. perl a
protectively coloured, 63.

BUCEROTIDJE, sexual colouring and
nidification of, 241.

BUCCOXID.E, sexual colouring and
nidification of, 241.

BUFF-TIP moth, resembles a broken
stick, 62.

BUILDINGS of various races do not
change, 213.

BUPRESTID.E, resembling bird'*
dung, 57 ; similar colours in
two sexes, 114.

BUTTERFLIES, value of, in studying
" natural selection," 131 ; varie-
ties of, in Sardinia and Isle of
Man, 178.

CACIA anthriboules, 94.

Callizona acesta. protective colour-
ing of, 59.

CALORNIS, 239.

CAPITONID.E, sexual colouring and
nidification of, 241.

Capnolymma stygium, 94.

CARABID.E, special protection
among, 72 ; similar colouring
of two sexes, 114.

CASSID.E, resemble dew drops, 58.

CATERPILLARS, mimicking a poi-
sonous snake, 99 ; gaudy co-
lours of, 117 ; various modes of
protection of, 118; gooseberry
caterpillar, 119 ; Mr. Jenner
Weir's observations on, 119;
Mr. A. G. Butler's observations
on, 121.

INDEX.

CELEBES, local modifications of
form in, 170 ; probable cause of
these, 176; remarkable zoolo-
gical peculiarities of, 195-199.

CENTROPUS, sexual colouring and
nidification of, 242.

Ccphalodonta spinipes, 92.

Ceroxylus laceratus, imitates a
moss covered stick, 64.

CERTHIOLA, sexual colouring and
nidification of, 244.

Cethosia (sole, 172 ; biblis, 172.

CETONIAD.E, how protected, 73;
similar colours of two sexes,
114.

CEYOOPSIS, 196.

Charis melipona, 96.

CIIEMATOBIA, wintry colours of this
genus, 62.

Chlamys pilula, resembles dung of
caterpillars, 58.

CIIRYSIDID.E, how protected, 72.

CHRYSOMELID.E, similar colouring
of two sexes, 1 14.

CICINDELA, adaptive colour of va-
rious species of, 57.

Cilix compressa, resembles bird's
dung, 63.

CLADOBATES, mimicking squirrels,
107.

CLASSIFICATION, form of true, 6;
circular, inadmissible, 8 ; quina-
rian and circular, of Swainson,
46; argument from, against
Mr. Dar.win, 295.

CLIMACTERIS, sexual colouring and
nidification of, 243.

COCCINELLID^E, how protected, 72;
similar colouring of sexes, 114.

COEXISTING varieties, 159.

Colly r odes lacordairei, 95.

COLOUR, in animals, popular theo-
ries of, 47 ; frequent variations
of, in domesticated animals, 48;
influenced by need of conceal-
ment, 49 ; in deserts, 49, 50 ;
in Arctic regions, 50, 51 ; noc-
turnal, 51 ; tropical, 52 ; special
modifications of, 52 ; different
distribution of, in butterflies
and moths, 58 ; of autumnal
and winter, moths, 62 ; white,
generally dangerous and there-
fore eliminated, 66 ; why it
exists so abundantly although
often injurious, 69 ; influenced
by need of protection, 113; of
female birds, 114; in relation to
nidification of birds, 116 ; gaudy
colours of many caterpillars,
117; in nature, general causes
of, 126 ; local variations of,
173 ; sexual differences of, in
birds, 239 ; in female birds, how
connected with their nidifica-
tion, 240, 246; more variable
than structure or habits, and
therefore more easily modified,
249 ; of flowers, as explained by
Mr. Darwin, 262 ; often corre-
lated with disease, 316.

COMPSOGNATHUS, 300.

Condylodera tricondyloides, 97.

CONSCIOUSNESS, origin of, 360;
Professor Tyndall on, 361 ; not
a product of complex organiza-
tion, 365.

CORRELATION of growth, 310.

Corynomalus sp., 92.

COTINGID.E, sexual colouring and
nidification of, 244.

CRATOSOMUS, a hard weevil, 94.

370

2XDEX.

CRICKETS mimicking sand wasps,
98.

CRYPTODONTIA, 299.

Oucullia verbasci, 120.

CURCULIONID.E, often protected by
hard covering, 71 ; similar co-
lours of two sexes, 114.

Cuviera squamata, 258.

Cyclopeplus batesii, 92.

CYNOPITHECUS, 196.

Cynthia arsinoe, 172.

DANAID.H, the subjects of mimi-
cry, 85, 80.

Danais erippus, 88; cfirysippus,
112; sobrina, 179; aglaia, 179;
tytia, 180.

DARWIN, Mr., his principle of uti-
lity, 47 ; on cause of colour in
flowers, 127, 262 ; on colours of
caterpillars, 118; on sexual co-
louration, 260; his metaphors
liable to misconception, 269 ;
criticism of, in North British
Review, 291.

DESERT animals, colours of, 49, 50.

DIADEMA, species of, mimic Danai-
dre, 86, 87 : female with male
colouration, 112.

Diudema misippits, 112; D. ano-
mala, 113.

Diaphora mendica, 89.

DlCNYODONTIA, 299.

DICROURUS, 253.

Diloba cxruleoccphala, 120.

DIMORPHISM, 145 ; in beetles, 155 ;

in birds, 155 ; illustrated, 157.
DINOSAURIA, 298.
DIPTERA mimicking wasps and

bees, 97.

ionLls*, 91.

DOMESTICATED animals, their essen-
tial difference from wild one?,
38-41.

DOTTERELL, 251.

DRUSILLA, mimicked by three ge-
nera, 181.

Drusilla bioculata, 180.
DVTISCUS, dimorphism in, 155.

EGYPTIAN architecture, intro-
duced, 225.

Elapsfulvius, E. corcdlinus, E. lem-
niscatus, 101 ; E. mipartitus, E.
lemniscatus, E. hemiprichii, 102.

ENODES, 196.

EXNOMUS, autumnal colours of this
genus, 62.

Eosfuscata, dimorphism of, 155.

EQUUS, 299.

Eronia tritcea, 172; Valeria, 172.

Eroschema poweri, 93.

ERYCINID.E mimic Heliconidag, 84.

Erythroplatis corallifer, 92.

ESTRELDA, sexual colouring and
nidification of, 243.

EUCNEMID.E, mimicking a Malaco-
derm, 93.

Eudroniias morinellus, 251.

Euglossa dimidiata, 98.

EUMORPHID,E, a protected group,
72 ; imitated by Longicorns, 92.

EUPLOSA, local modifications of co-
lour in, 173.

Euploea midamus, 87-113, 179 ;
E. rhadamantkus, 87, 179.

Eurhinia megalonice, 172; poly-
nice, 17:\

EURYL.EMID.E, sexual colouring and
nidification of, 243.

EXTINCT animala, intermediate
forms of, 298.

INDEX.

377

EXTINCTION of lower races, 318.

FEMALE birds, colours of, 114;
sometimes connected with their
mode of nidification, 240 ; more
exposed to enemies than the
males, 248.

FEMALE butterflies generally dull-
coloured, 259.

FEMALE insects, mimicry by, 110,
259; colours of, 113.

FEMALE sex, has no incapacity for
as brilliant colouration as the
male, 247 ; in some groups re-
quires more protection than the
male, 258.

FISHES, protective colouring of, 55.

FISSIROSTRAL birds, nests of, 238.

FLOWERS, causes of colour in, 127.

FLYCATCHERS, genera of, absent
from Celebes, 177.

FORBES, EDWARD, objections to his
theory of Polarity, 17-23.

FORCE is probably all Will-force,
366.

GALAPAGOS, 10.

GALTOX, Mr., on range of intellec-
tual power, 339.

GANOCEPHALA, 298.

GastropacJia qucrci, protective co-
lour and form of, 6:?.

GAUDRV, M., on fossil mammals of
Greece, 299.

GEOGRAPHICAL distribution, de-
pendent on geologic changes, 1 ;
its agreement with law of in-
troduction of new species, 9 ;
of allied species and groups, 12.

GEOLOGICAL distribution analogous
to geographical, 13.

GEOLOGY, facts proved by, 2-5.

GIRAFFE, how it acquired its long
neck, 42.

GL.EA, autumnal colours of this
genus, 62.

GOULD, Mr., on sexual plumage of
Gray Phalarope, 115; on incu-
bation by male Dotterell, 115.

Grallina ausindis, 254.

GREEN birds almost confined to
the tropics, 52.

G-ymnocerus cratosomoides, 94.

Gymnocerous capucinus, 96.

Gymnocerous dulcissimus, 97.

GUNTIIER, Dr., on arboreal snakes,
55 ; on colouring of snakes, 102.

G-ynecia dirce, 59.

HABITS, often persistent when
use of them has ceased, 234 ; of
children and savages analogous
to those of animals, 235 ; if
persistent and imitative may be
termed hereditary, 235, 236.

HAIRY covering of Mammalia, use
of, 344 ; absence of, in man re-
markable, 345; the want of it
felt by savages, 346 ; could not
have been abolished by natural
selection, 348.

Harpagus diodon, 107.

HEILIPLUS, a hard genus of Cur-
culionidae, 94.

HELICON ID.E, the objects of mimi-
cry, 77 ; their secretions, 88 ;
not attacked by birds, 79; some-
times mimicked by other Heli-
conidjE, 85.

HELLADOTHERIUM, 300.

HEMIPTERA, protected by bad
odour, 72.

378

JSDEX.

HERBERT, Rev. W., on song of

birds, 221.
HESPERID.E, probable means of

protection of, 176.
HESTIIESLS, longicorns resembling

ants, 96.

Hestia leuconoe, 180.
HEWITSON, Mr., 131.
HIPPARION, 299.

HlPPOTIIERIUM, 299.

HISPID.E, imitated by Longicorns,
92.

IIOLOTHURIDjE, 258.

Homalocranium semicinctum, 101.
HOOKER, Dr., on the value of the

" specific term," 165.
HOUSES of American and Malay

races contrasted, 213.
HUXLEY, Professor, on " Physical

Basis of Life," 362 ; on volition,

368.

HY.ENICTIS, 300.
HYBERNIA, wintry colours of this

genus, 62.
HYMENOPTERA, large number of,

peculiar to Celebes, 196.

ICTERID JE, sexual colouring and
nidification of, 244.

ICTIIYOPTERYGIA, 298.

Ideopsis daos, 180.

IMITATION, the effects of, in man's
works, 212.

INDIANS, how they travel through
trackless forests, 207.

INSECTS, protective colouring of,
56 : mimicking species of other
orders, 97 ; senses of, perhaps
different from ours, 202, 203.

INSTINCT, how it may be best stu-
died, 201 ; definition of, 203 ;

in many cases assumed without
proof, 205 ; if possessed by man,
206 ; supposed, of Indians, 207 ;
supposed to be shown in the
construction of birds' nests, 211.

INTELLECT of savages compared
with that of animals, 341.

INTELLECTUAL power, range of, in
man, 339.

Iphias glaucippe, 172.

ITHOMIA, mimicked by Leptalis, 83.

Ithomia ilerdina, mimicked by four
groups of Lepidoptera, 84.

JAVA, relations of, to Sumatra

and Borneo, 193.
JAMAICA swift altering position of

nest, 228.
JERDON, Mr., on incubation by

males in Turnix, 115.

KALLIMA inavhis and Kallima
paraleJcta, wonderful resem-
blance of, to leaves, 59-61.

LABYEINTHODONTIA, 298,
300.

LAKES as cases of imperfect adapt-
ation, 278.

LANIAD.E, sexual colouring and ni-
dification of, 245.

LAMARCK'S hypothesis very dif-
ferent from the author's, 41.

Larentia tripunctaria, 63.

LAW which has regulated the in-
troduction of new species, 5 ;
confirmed by geographical dis-
tribution, 9 ; high organization
of ancient animals consistent
with, 14; of multiplication in
geometrical progression, 265 ;

INDEX.

379

of limited populations, 265 ; of
heredity, 266 ; of variation,
266 ; of change of physical con-
ditions, 266 ; of the equilibrium
of nature, 266 ; as opposed to
continual interference, 268.

LAY COCK, Dr., on law of " uncon-
scious intelligence," 360.

LEAP BUTTERFLY, appearance and
habits of, 59-61.

LEPIDOPTEUA, especially subject to
variation, 132.

LEPTALIS, species of mimic Ileli-
conidte, 82 ; gain a protection
thereby, 259.

LESTER, Mr. J. M., on wood-dove
and robin, 53.

LEVAILLANT, on formation of a
nest, 224.

Limenltis archippus, 88.

Limenitis limire, 172 ; procris, 172.

LIZARDS refusing certain moths
and caterpillars, 121 ; devour-
ing bees, 121.

LOCAL FORMS, 158.

LOCAL variation of form, 169 ; of
colour, 173 ; general remarks
on, 174 ; in Celebesian butter-
flies, probable use of, 175.

LOCUSTID.E, adaptive colouring of,
64.

LUMIXOUSNESS of some insects a
protection, 71.

LYC.EXID.E, probable means of pro-
tection of, 176.

MAMMALS, mimicry among, 107.

MAX, does he build by reason or
imitation, 212; his works mainly
imitative, 225 ; antiquity of, 303,
322 ; difference of opinion as to

his origin, 304 ; unity or plural-
ity of species, 305 ; persistence
of type of, 306 ; importance of
mental and moral characters,
312; his dignity and supremacy,
324 ; his influence on nature,
326; his future development,
326; range of intellectual power
in, 339; rudiments of all the
higher faculties in savage, 341 ;
his feet and hands, difficulties
on the theory of natural selec-
tion, 349: his voice, 350; his
mental faculties, 351 ; difficulty
as to the origin of the moral
sense in, 352 ; development of,
probably directed by a superior
intelligence, 359.

MANTID.E, adaptive colouring of,
64 ; mimicking white ants, 98.

MALACODEKMS, a protected group,
93.

MALURIDJE, 255.

MATTER, the nature of, 363 ; Mr.
Bayma on, 363 ; is force, 365.

MECHANITIS and Methona, mi-
micked by Leptalis, 83.

MECOCERUS, dimorphism of, 155.

Mecocerus gazella, 94.

MEGACEPHALON, 196.

MEGAPODID.E, sexual colouring and
nidification of, 246.

MEIIOPOGOX, 196.

Midas dives, 97.

MIMETA, mimicking Tropidorhyn-
chus, 104.

MIMICRY, meaning of the word,
74 ; theory of, 76 ; among Lepi-
doptera, 77 ; how it acts as a
protection, 80, 81 ; of other in-
sects by Lepidoptera, 89; among

380

INDEX.

beetles, 91 ; of other insects b'y
beetles, 95 ; of insects by species
of other orders, 97 ; among the
vertebrate,, 99; among snake?,
101 ; among tree frogs, 103 ;
among birds, 103; among mam-
mals, 107 ; objections to the
theory of, 108 ; by female in-
sects, 110; among Papilionida^
179; never occurs in the male
only, 2; 0.

MOMOTID.E, sexual colouring and
nidification of, 241.

MONTROUZIER, M., on butterflies
of Woodlark Island, 152.

MORAL sense, difficulty as to the
origin of, 352.

MORPIIOS, how protected, 73.

MURRAY, Mr. Andrew, objections
to theory of mimicry, 108.

MUSCICAPID.E, sexual colouring
and nidification of, 245.

MUSOPIIAGID.E, sexual colouring
and nidification of, 242.

NAPEOGENES, all the species

\ are miraickers, 85.

NATURAL selection, the principle
stated, 41-43; general accept-
ance of the theory of, 46 ;
tabular demonstration of, 302 ;
outline of theory of, 307 ; its
effects on man and animals dif-
ferent, 311 ; hardly acts among
civilized societies, 330 ; what it
can not do, 333 ; cannot pro-
duce injurious or useless modi-
fications, 334.

NECTARINEID.E, 254.

NECYDALIDJJ, mimic Hymenop-
tera, 96.

Nemophas grayi, a Longicorn mi-
micked by a Longicorn, 95.

NESTS of Birds, why different,
215 ; of young birds, how built,
219; construction of, described
by Levaillant, 224; imperfec-
tions in, 229 ; influenced by
changed conditions and per-
sistent habits, 232 ; classification
of, according to function, 237.

NEW FORMS, how produced by
variation and selection, 286.

NEW GUINEA, relation of the seve-
ral Papuan islands to, 194.

NOCTURNAL animals, colours of,
51.

NOMADA, 98.

OBEREA, species resemble Ten-
thredinidae, 96.

Odontocera odyneroides, 96.

ODONTOCIIEILA, 97.

Odynerus sinuatus, 90.

Onthophilus sulcatus, like a seed,
58.

Onychocerus scorpio, resembles
bark, 56.

ORANGE TIP butterfly, protective
colouring of, 59.

ORCHIS, structure of an, explained
by natural selection, 271.

Orgyia antiqua and 0. gonoatigma,
autumnal colours of, 62.

ORIOLIDJS, 253.

Ornithoptera priamus, 145, 173 ;
0. kelcna, 173.

Oxyrhopus petolarius, 0. trigemi-
nus, 0. formosus, 102.

CWEX, Professor, on more gene-
ralized structure of extinct ani-
mals, 298.

IXDEX.

381

PA CHYO TRIS fabricii, 96.

PACHYRIIYXCIII, weevils mimicked
by Longicorns, 95.

PALEOTIIEIUUM, 299.

PALOPLOTHERIUM, 299.

PAPILIO, black and red group imi-
tated, 84.

Papilio achates, 147 ; P. adaman-
tius, 111 ; P. (Enigma, 87 ; P.
agamernnon, 141, 158, 170, 171 ;
P. agestor, 180 ; P. alpkenor,
148, 169 ; P. amanga, 151 ; P.
androcles, 171 ; P. androgeus, 88,
147, 180, 183; P. antiphates,
141, 171 ; P. antiphus, 87, 150,
170, 180, 183 ; P. aristaws. 171 ;
P. arjuna, 141 ; P. ascalaphits,
171 ; P. autolycus, 160 ; P. bathy-
clcs, 141 ; P. blumei, 171 ; P.
brama, 171 ; P. caunus, 87, 179 ;
P. corfrws, 160, 171 ; P. cow?, 88,
146, 180, 182 ; P. deiphobus, 140 ;
P. deiphontes, 171 ; P. delessertii,
180 ; P. demotion, 171 ; P. c%Ai-
foa, 87, 170, 180, 183 ; P. double-
day i, 88, 180; P. elyros, 148 ; P.
encelades, 171 ; P. erect heiis, 151 ;
P. euripilus, 160; P. evcmon,
159 ; P. gigon, 171 ; P. glaucus,
152; P. focfor, 87, 150, 180, 183;
P. Menus, 160, 171 ; P. hospi-
ton, 178; P. idaoides, 180; P.
;Vwo», 159, 171 ; P. ledebouria,
148 ; P. lettcotkoe, 171 ; P. ?eorfa-
mas, 170 ; P. Kris, 87, 1<Q,0, 184 ;
P. macareus, 179; P. mackaon,
178 ; P. melanides, 148, 150 ; P.
memnon, 88, 140, 146, 117, 152,
180, 183; P. wztfow, 171; P. ne.
jjhelus, 140; P, meaner, 170; P
cenomaus, 88, 180, 184; P.onesi-

mus, 151 ; P. ormcnus, 150, 152,
182; P.pammon, 147, 152, 170,
180; P. pamphylus, 171; P.
pandion, 152, 180; P. paradoxa,
87, 179 ; P. peranthus, 160, 171 ;
P. pcrtinctXj 145 ; P. philoxenus,
182 ; P. polydorus, 88, 170, 182 ;
P. polytes, 147, 148 ; P. rfosus,
171 ; P. romulus, 87, 143, 15'J,
183 ; P. sarpedon, 141, 158, 171 ;
P. sataspes, 171 ; P. sevcnts,
140, 144; P. f&wews, 87, 148,
150, 169, 170, 171, 180, 183 : P.
fAwfe, 179; P. torquatus, 156;
P. turnus, 152; P. ulysses, 140,
160, 173; P.varuna, 88.

PAPILIONID.E, the question of their
rank, 133 ; peculiar characters
possessed by, 134; peculiarly
diurnal, 136; compared with
groups of mammalia, 138 ; dis-
tribution of, 140 ; large forms
of Celebes and Moluccas, 168;
large forms of Amboyna, 169;
local variation of form, 139;
arrangement of, 186 ; geogra-
phical distribution of, 189 ; of
Indo-Malay and Austro-Malay
regions, 192; of Java, Suma-
tra, and Borneo, 193.

PARID.E, sexual colouring and nidi-
fication of, 243.

PASSENGER pigeon, cause of its
great numbers, 308.

PATENT inventions, as illustrating
classification, 295.

Phacellocsra bates ii, mimics one of
the Anthribklas.

Phalaropusfulicarius, 115, 251.

PHASUiD.fi, imitate sticks and

382

INDEX.

twig?, 64 ; females resembling
leaves, 112.

PIIYLLIUM, wonderful protective
colour and form of, 64.

PHYSALIA, 258.

PIERID.E, local modification of
form in, 172.

PIEKIS, females only imitating
Heliconidse, 112.

Pier is coronis, 172; eperia, 172.

Pieris pyrrha, 113.

PICID.E, sexual colouring and nidi-
fication of, 242.

PIPRID.E, sexual colouring and
nidification of, 245.

PITTID^, 253.

Pliocerus egualis, 101 ; P. elapoides,
P. euryzonus. 102.

Pfsciloderma terminate, 93.

POLARITY, Forbes' theory of, 17,
45.

POLYMORPHISM, 145; illustration
of, 157.

POPULATION of species, law of, 28 ;
does not permanently increase,
29; not determined by abun-
dance of offspring, 29; checks
to, 30 ; difference in the case of
cats and rabbits explained, 32.

PREVISION, a case of, 122.

PKIONITURUS, 196.

PROTECTION, various modes in
which animals obtain it, 69-71,
258 ; greater need of, in female
insects and bird?, 113.

PROTECTIVE colouring, theory of,
65.

PSITTACI (Parrots), sexual colour-
ing and nidification of, £42.

PTEROSAURIA, 298.

PTYCIIODERES, 94.

EACES, or subspecies, 160; of
man, origin of, 319.

EEDBREAST and woodpigeon, pro-
tective colouring of, 53, 54.

EEPRESENTATIVE groups, 9; of Tro-
gons, butterflies, &c., 12.

EEPTILES, protective colouring of,
54.

EIIAMPHASTID.E, sexual colouring
and nidification of, 242.

EHIXOCEROS, 299.

EIVER system, as illustrating self-
adaptation, 276.

EOSES, Mr. Baker on varieties of,
165.

EUDIMENTARY organs, 23.

SALVIN, Mr. Osbert, on a case of
bird mimicry, 107.

Saturn ia pavonia-minor, protective
colouring of larva of, 63.

SATYRLD.E, probable means of pro-
tection of, 176.

SAUROPTERYGIA, 299.

SAVAGES, why they become extinct,
319 ; undeveloped intellect of,
339, 341 ; intellect of, compared
with that of animals, 341, 343;
protect their backs from rain,
346.

SCANSORIAL birds, nests of, 238.

SCAPIIURA, 98.

SCISSIROSTRUM, 165.

SCOPULIPEDES, brush-legged bees,
91.

ScuDDER,Mr.,on fossil insects, 301.

SCUTELLERID.E, mimicked by Long-
icorns, 96.

Sesia bombiliformis, 90.

SESUD.E, mimic Hymenoptera, 90.

SEXES, comparative importance of,

INDEX.

383

in different classes of animals,
111; diverse habits of, 156.

SEXUAL SELECTION, 156; its nor-
mal action to develop colour in
both sexes, 247; among birds,
283.

SIDGWICK, Mr. A., on protective
colouring of moths, 62.

SIMOCYONID.E, 300.

SITTA, sexual colouring and nidi-
fication of, 243.

SITTELLA, sexual colouring and
nidification of, 243.

SNAKES, mimicry among, 101.

SONG of birds, instinctive or imita-
tive, 220.

SPECIES, law of population of, 28 ;
abundance or rarity of, depend-
ent on the adaptation to condi-
tions, 33; definition of, 141,
161 ; the range and constancy
of, 143; extreme variation in,
163, 164.

SPEED of animals, limits of, 292.

Sphecia craboniforme, 90.

Sphecomorpha chalybea, 96.

SPIIEGID.E, mimicked by flies, 97.

SPIDERS, which minac ants, 98 ;
and flower buds, 99.

Spilosoma menthastri, 88.

STAINTON, Mr., on moths rejected
by turkeys, 78, 88.

STALACIITIS, a genus of Erycinida?,
the object of mimicry, 84.

STINGING insects generally conspi-
cuously coloured, 72.

STREPTOCITTA, 196.

STUKNID.E, sexual colouring and
nidification of, 244.

STUKNOPASTOR, 239.

ST. HELENA, 10.

Streptolabis hispoides, 93.

STRUGGLE for existence, 28, 33.

SURVIVAL of the fittest, law of,
stated, 33 ; its action in deter-
mining colour, 67.

SWAINSON'S circular and quinarian
theory, 45.

SYLVIAD.E, sexual colouring and
nidification of, 245.

SYNAPTA, 258.

TACHORNIS pJuenicobea, 228.
Tachyris hombronii, 172; it home,

172 ; lycaste, 172 ; lyncida, 172 ;

nephele, 172; nero, 172; zarinda,

172.
TANAGRID/E, sexual colouring and

nidification of, 245.
TAPIR, 299.
TELEPHORI, similar colouring of

two sexes, 114.

TEMPERATE and cold climates fa-
vourable to civilization, 318.
THECODONTIA, 299.
TIIEUATES, mimicked by Hetero-

mera, 95.
Thyca descombesi, 172 ; Jiyparete,

172; rosenbergii, 172; zebudn,

172.

TIGER, adaptive colouring of, 52.
TIMES newspaper on Natural Selec-
tion, 296.
TOOLS, importance of, to man,

314.
TREE FROGS, probable mimicry by,

103.

TRICONDYLA, 97.
TRIMEX, Mr., on rank of the Papi-

lionidw, 136.
TRISTRAM, Kev. II., on colours of

desert animals, 50,

384

INDEX.

TrcchUium tipuliforme, 90.

TROGONID.E, sexual colouring and

. nidification of, 241.

TROPICAL birds often green, 52.

TROPICS, most favourable to pro-
duction of perfect adaptation
among animals, 68 ; not favour-
able to growth of civilization,
318. '

TROPIDORHYNCIIUS mimicked by
orioles, 104.

TRUTHFULNESS of some savages,
353 ; not to be explained on
utilitarian hypothesis, 354.

TURDID.E, sexual colouring and
nidification of, 245.

TURNIX, 115, 251.

TYNDALL, Professor, on origin of
consciousness, 361.

TJPUPID^E, sexual colouring and
nidification of. 241.

USEFUL and useless variations, 34.

UTILITY, importance of the prin-
ciple of, 47, 127.

VARIABILITY, simple, 144.

VARIATIONS, useful and useless, 34;
laws of, 143, 266; as influenced
by locality, 166 ; of size, 168 ;
universality of, 287-291 ; are
there limits to, 291 ; of domestic
dogs, 293 ; of pigeons, 293.

VARIETIES, instability of, supposed
to prove the permanent dis-
tinctness of species, 26; if su-
perior will extirpate original
species, 36; its reversion then
impossible, 37 ; of domesticated
animals may partially revert,

38, 40; inconvenience of u<ing

the term, 161.

VERTEBRATA, mimicry among, 99.
VOICE of man, not explained by

natural selection, 350.
VOLUCELLA, species of mimic bees,

75, 98.

WALSH. Mr., on dimorphism, of
Papilio turnus, 153.

WEAPONS and tools, how they
affect man's progress, 314.

WEEVILS often resemble small
lumps of earth, 58.

WEIR, Mr. Jenner, on a moth
refused by birds, 89 ; on beetles
refused by birds, 93 ; on cater-
pillars eaten and rejected by
birds, 119.

WESTWOOD, Professor, objections
to theory of mimicry, 108.

WHITE colour in domesticated and
wild animals, 66.

WILD and domesticated animals,
essential differences of, 38-41.

WILL really exerts force, 357 ;
probably the primary source of
force, 368.

WOOD, Mr. T. W., on orange-tip
butterfly, 59.

WOODCOCKS and Snipes, protective
colouring of, 5'3.

WOODPECKERS, why scarce in Eng-
land, 32.

XANTHIA, autumnal colours of
these moths, 62.

ZEBRAS, 299.