and genera, or even families and orders, appear to arise suddenly,
without anything leading up to them. Even this the second difficulty,
however, admits of being fully met, when we remember that in very many
cases it has been proved, quite apart from the theory of descent, that
superjacent formations have been separated from one another by wide
intervals of time. And even although it often happens that intermediate
deposits which are absent in one part of the world are present in
another, we have no right to assume that such is always the case.
Besides, even if it were, we should have no right further to assume that
the faunas of widely separated geographical areas were identical during
the time represented by the intermediate formation. Yet, unless they
were identical, we should not expect the fossils of the intermediate
formation, where extant, to yield evidence of what the fossils would
have been in this same formation elsewhere, had it not been there
destroyed. Now, as a matter of fact, "geological formations of each
region are almost invariably intermittent"; and although in many cases a
more or less continuous record of past forms of life can be obtained by
comparing the fossils of one region and formation with those of another
region and adjacent formations, it is evident (from what we know of the
present geographical distribution of plants and animals) that not a few
cases there must have been where the interruption of the record in one
region cannot be made good by thus interpolating the fossils of another
region. And we must remember it is by selecting the cases where this
cannot be done that the objection before us is made to appear
formidable. In other words, _unless_ whole groups of new species which
are unknown in formation A appear suddenly in formation C of one region
(X), where the intermediate formation B is absent; and _unless_ in some
other region (Y), where B is present, the fossiliferous contents of B
fail to supply the fossil ancestry of the new species in A (X); _unless_
such a state of matters is found to obtain, the objection before us has
nothing to say. But at best this is negative evidence; and, in order to
consider it fairly, we ought to set against it the cases where an
interposition of fossils found in B (Y) _does_ furnish the fossil
ancestry of what would _otherwise_ have been an abrupt appearance of
whole groups of new species in A (X). Now such cases are neither few
nor unimportant, and therefore they deprive the objection of the force
it would have had if the selected cases to the contrary were the general
rule.
In addition to these considerations, the following, some of which are of
a more special kind, appear to me so important that I will quote them
almost _in extenso_.
We continually forget how large the world is, compared with the
area over which our geological formations have been carefully
examined: we forget that groups of species may elsewhere have long
existed, and have slowly multiplied, before they invaded the
ancient archipelagoes of Europe and the United States. We do not
make due allowance for the intervals of time which have elapsed
between our consecutive formations,--longer perhaps in many cases
than the time required for the accumulation of each formation.
These intervals will have given time for the multiplication of
species from some one parent form; and, in the succeeding
formation, such groups of species will appear as if suddenly
created.
I may here recall a remark formerly made, namely, that it might
require a long succession of ages, to adapt an organism to some new
and peculiar line of life, for instance, to fly through the air;
and consequently that the transitional form would often long remain
confined to some one region; but that, when this adaptation had
once been effected, and a few species had thus acquired a great
advantage over other organisms, a comparatively short time would be
necessary to produce many divergent forms, which would spread
rapidly and widely throughout the world....
In geological treatises, published not many years ago, mammals were
always spoken of as having abruptly come in at the commencement of
the tertiary series. And now one of the richest known accumulations
of fossil mammals belongs to the middle of the secondary series;
and true mammals have been discovered in the new red sandstone at
nearly the commencement of this great series. Cuvier used to urge
that no monkey occurred in any tertiary stratum; but now extinct
species have been discovered in India, South America, and in Europe
as far back as the miocene stage. Had it not been for the rare
accident of the preservation of footsteps in the new red sandstone
of the United States, who would have ventured to suppose that, no
less than at least thirty kinds of bird-like animals, some of
gigantic size, existed during that period? Not a fragment of bone
has been discovered in these beds. Not long ago palaeontologists
maintained that the whole class of birds came suddenly into
existence during the eocene period; but now we know, on the
authority of Professor Owen, that a bird certainly lived during the
deposition of the upper green-sand. And still more recently that
strange bird, the Archeopteryx ... has been discovered in the
oolitic slates of Solenhofen. Hardly any recent discovery shows
more forcibly than this, how little we as yet know of the former
inhabitants of the world.
I may give another instance, which, from having passed under my own
eyes, has much struck me. In a memoir on Fossil Sessile Cirripedes,
I stated that, from the number of existing and extinct tertiary
species; from the extraordinary abundance of the individuals of
many species all over the world from the Arctic regions to the
equator, inhabiting various zones of depths from the upper tidal
limits to 50 fathoms; from the perfect manner in which specimens
are preserved in the oldest tertiary beds; from the ease with which
even a fragment of a valve can be recognized; from all these
circumstances, I inferred that had sessile cirripedes existed
during the secondary periods, they would certainly have been
preserved and discovered; and as not one species had then been
discovered in beds of this age, I concluded that this great group
had been suddenly developed at the commencement of the tertiary
series. This was a sore trouble to me, adding as I thought one more
instance of the abrupt appearance of a great group of species. But
my work had hardly been published, when a skilful palaeontologist,
M. Bosquet, sent me a drawing of a perfect specimen of an
unmistakeable sessile cirripede, which he had himself extracted
from the chalk of Belgium. And, as if to make the case as striking
as possible, this sessile cirripede was a Chthamalus, a very
common, large, and ubiquitous genus, of which not one specimen has
as yet been found even in any tertiary stratum. Still more
recently, a Pyrgoma, a member of a distinct sub-family of sessile
cirripedes, has been discovered by Mr. Woodward in the upper chalk;
so that we now have abundant evidence of the existence of this
group of animals during the secondary period.
The case most frequently insisted on by palaeontologists of the
apparently sudden appearance of a whole group of species, is that
of the teleostean fishes, low down, according to Agassiz, in the
Chalk period. This group includes the large majority of existing
species. But certain Jurassic and Triassic forms are now commonly
admitted to be teleostean; and even some palaeozoic forms have been
thus classed by one high authority. If the teleosteans had really
appeared suddenly in the northern hemisphere, the fact would have
been highly remarkable; but it would not have formed an insuperable
difficulty, unless it could likewise have been shown that at the
same period the species were suddenly and simultaneously developed
in other quarters of the world. It is almost superfluous to remark
that hardly any fossil fish are known from south of the equator;
and by running through Pictet's Palaeontology it will be seen that
very few species are known from several formations in Europe. Some
few families of fish now have a confined range; the teleostean fish
might formerly have had a similarly confined range, and after
having been largely developed in some one sea, might have spread
widely. Nor have we any right to suppose that the seas of the world
have always been so freely open from south to north as they are at
present. Even at this day, if the Malay Archipelago were converted
into land, the tropical parts of the Indian Ocean would form a
large and perfectly enclosed basin, in which any great group of
marine animals might be multiplied; and here they would remain
confined, until some of the species became adapted to a cooler
climate, and were enabled to double the southern capes of Africa or
Australia, and thus reach other and distant seas.
From these considerations, from our ignorance of the geology of
other countries beyond the confines of Europe and the United
States; and from the revolution in our palaeontological knowledge
effected by the discoveries of the last dozen years, it seems to me
to be about as rash to dogmatize on the succession of organic
forms throughout the world, as it would be for a naturalist to
land for five minutes on some one barren point in Australia, and
then to discuss the number and range of its productions[53].
[53] _Origin of Species_, 282-5.
In view of all the foregoing facts and considerations, it appears to me
that the second difficulty on our list is completely answered. Indeed,
even on a moderate estimate of the imperfection of the geological
record, the wonder would have been if many cases had _not_ occurred
where groups of species present the fictitious appearance of having been
suddenly and simultaneously created in the particular formations where
their remains now happen to be observable.
Turning next to the third objection, there cannot be any question that
every here and there in the geological series animals occur of a much
higher grade zoologically than the theory of evolution would have
expected to find in the strata where they are found. At any rate,
speaking for myself, I should not have antecedently expected to meet
with such highly differentiated insects as butterflies and dragonflies
in the middle of the Secondaries: still less should I have expected to
encounter beetles, cockroaches, spiders, and May-flies in the upper and
middle Primaries--not to mention an insect and a scorpion even in the
lower. And I think the same remark applies to a whole sub-kingdom in the
case of Vertebrata. For although it is only the lowest class of the
sub-kingdom which, so far as we positively know, was represented in the
Devonian and Silurian formations, we must remember, on the one hand,
that even a cartilaginous or ganoid fish belongs to the highest
sub-kingdom of the animal series; and, on the other hand, that such
animals are thus proved to have abounded in the very lowest strata where
there is good evidence of there having been any forms of life at all.
Lastly, the fact that Marsupials occur in the Trias, coupled with the
fact that the still existing Monotremata are what may be termed animated
fossils, referring us by their lowly type of organization to some period
enormously more remote,--these facts render it practically certain that
some members of this very highest class of the highest sub-kingdom must
have existed far back in the Primaries.
These things, I say, I should not have expected to find, and I think all
other evolutionists ought to be prepared to make the same
acknowledgment. But as these things have been found, the only possible
way of accounting for them on evolutionary principles is by supposing
that the geological record is even more imperfect than we needed to
suppose in order to meet the previous objections. I cannot see, however,
why evolutionists should be afraid to make this acknowledgment. For I do
not know any reason which would lead us to suppose that there is any
common measure between the distances marked on our tables of geological
formations, and the times which those distances severally represent. Let
the reader turn to the table on page 163, and then let him say why the
30,000 feet of so-called Azoic rocks may not represent a greater
duration of time than does the thickness of all the Primary rocks above
them put together. For my own part I believe that this is probably the
case, looking to the enormous ages during which these very early
formations must have been exposed to destructive agencies of all kinds,
now at one time and now at another, in different parts of the world.
And, of course, we are without any means of surmising what ranges of
time are represented by the so-called Primeval rocks, for the simple
reason that they are non-sedimentary, and non-sedimentary rocks cannot
be expected to contain fossils.
But, it will be answered, the 30,000 feet of Azoic rocks, lying above
the Primeval, _are_ sedimentary to some extent: they are not all
completely metamorphic: yet they are all destitute of fossils. This is
the fourth and last difficulty which has to be met, and it can only be
met by the considerations which have been advanced by Lyell and Darwin.
The former says:--
The total absence of any trace of fossils has inclined many
geologists to attribute the origin of the most ancient strata to an
azoic period, or one antecedent to the existence of organic beings.
Admitting, they say, the obliteration, in some cases, of fossils by
plutonic action, we might still expect that traces of them would
oftener be found in certain ancient systems of slate, which can
scarcely be said to have assumed a crystalline structure. But in
urging this argument it seems to be forgotten that there are
stratified formations of enormous thickness, and of various ages,
some of them even of tertiary date, and which we know were formed
after the earth had become the abode of living creatures, which
are, nevertheless, in some districts, entirely destitute of all
vestiges of organic bodies[54].
[54] _Elements of Geology_, p. 587.
He then proceeds to mention sundry causes (in addition to plutonic
action) which are adequate to destroy the fossiliferous contents of
stratified rocks, and to show that these may well have produced enormous
destruction of organic remains in these oldest of known formations.
Darwin's view is that, during the vast ages of time now under
consideration, it is probable that the distribution of sea and land over
the earth's surface has not been uniformly the same, even as regards
oceans and continents. Now, if this were the case, "it might well happen
that strata which had subsided some miles nearer to the centre of the
earth, and which had been pressed on by an enormous weight of
superincumbent water, might have undergone far more metamorphic action
than strata which have always remained nearer to the surface. The
immense areas in some parts of the world, for instance in South America,
of naked metamorphic rocks, which must have been heated under great
pressure, have always seemed to me to require some special explanation;
and we may perhaps believe that we see, in these large areas, the many
formations long anterior to the Cambrian epoch in a completely
metamorphosed and denuded condition[55]." The probability of this view
he sustains by certain general considerations, as well as particular
facts touching the geology of oceanic islands, &c.
[55] _Origin of Species_, p. 289.
On the whole, then, it seems to me but reasonable to conclude, with
regard to all four objections in question, as Darwin concludes with
regard to them:--
For my part, following out Lyell's metaphor, I look at the
geological record as a history of the world imperfectly kept,
written in a changing dialect; of this history we possess the last
volume alone, relating only to two or three countries. Of this
volume, only here and there a short chapter has been preserved; and
of each page only here and there a few lines. Each word of the
slowly-changing language, more or less different in the successive
chapters, may represent the forms of life, which are entombed in
our consecutive formations, and which falsely appear to us to have
been abruptly introduced. On this view, the difficulties above
discussed are greatly diminished, or even disappear[56].
[56] _Ibid._
As far as I can see, the only reasonable exception that can be taken to
this general view of the whole matter, is one which has been taken from
the side of astronomical physics.
Put briefly, it is alleged by one of the highest authorities in this
branch of science, that there cannot have been any such enormous reaches
of unrecorded time as would be implied by the supposition of there
having been a lost history of organic evolution before the Cambrian
period. The grounds of this allegation I am not qualified to examine;
but in a general way I agree with Prof. Huxley in feeling that, from the
very nature of the case, they are necessarily precarious,--and this in
so high a degree that any conclusions raised on such premises are not
entitled to be deemed formidable[57].
[57] See _Lay Sermons_, Lecture on Geological Reform.
* * * * *
Turning now to plants, the principal and the ablest opponent of the
theory of evolution is here unquestionably Mr. Carruthers[58]. The
difficulties which he adduces may be classified under three heads, as
follows:--
[58] See especially the following Presidential addresses:--Geol.
Assoc. Nov. 1876; Section D. Brit. Assoc., 1886; Lin. Soc., 1890.
1. There is no evidence of change in specific forms of existing plants.
Not only are the numerous species of plants which have been found in
Egyptian mummies indistinguishable from their successors of to-day; but,
what is of far more importance, a large number of our own indigenous
plants grew in Great Britain during the glacial period (including under
this term the warm periods between those of successive glaciations), and
in no one case does it appear that any modification of specific type has
occurred. This fact is particularly remarkable as regards leaves,
because on the one hand they are the organs of plants which are most
prone to vary, while on the other hand they are likewise the organs
which lend themselves most perfectly to the process of fossilization, so
that all details of their structure can be minutely observed in the
fossil state. Yet the interval since the glacial period, although not a
long one geologically speaking, is certainly what may be called an
appreciable portion of time in the history of Dicotyledonous plants
since their first appearance in the Cretaceous epoch. Again, if we
extend this kind of enquiry so as to include the world as a whole, a
number of other species of plants dating from the glacial epoch are
found to tell the same story--notwithstanding that, in the opinion of
Mr. Carruthers, they must all have undergone many changes of environment
while advancing before, and retreating after, successive glaciations in
different parts of the globe. Or, to quote his own words:--"The various
physical conditions which of necessity affected these {41} species in
their diffusion over such large areas of the earth's surface in the
course of, say, 250,000 years, should have led to the production of many
varieties; but the uniform testimony of the remains of this considerable
pre-glacial flora, as far as the materials admit of a comparison, is
that no appreciable change has taken place."
2. There is no appearance of generalized forms among the earliest plants
with which we are acquainted. For example, in the first dry land
flora--the Devonian--we have representatives of the _Filices_,
_Equisetaceae_, and _Lycopodiaceae_, all as highly specialized as their
living representatives, and exhibiting the differential characters of
these closely related groups. Moreover, these plants were even more
highly organized than their existing descendants in regard to their
vegetative structure, and in some cases also in regard to their
reproductive organs. So likewise the Gymnosperms of that time show in
their fossil state the same highly organized woody structure as their
living representatives.
3. Similarly, and more generally, the Dicotyledonous plants, which first
appear in the Cretaceous rocks, appear there suddenly, without any forms
leading up to them--notwithstanding that "we know very well the
extensive flora of the underlying Wealden." Moreover, we have all the
three great divisions of the Dicotyledons appearing together, and so
highly differentiated that all the species are referred to existing
genera, with the exception of a very few imperfectly preserved, and
therefore uncertain fragments.
Such being the facts, we may begin by noticing that, even at first
sight, they present different degrees of difficulty. Thus, I cannot see
that there is much difficulty with regard to those in class 2. Only if
we were to take the popular (and very erroneous) view of organic
evolution as a process which is always and everywhere bound to promote
the specialization of organic types--only then ought we to see any real
difficulty in the absence of generalized types preceding these existing
types. Of course we may wonder why still lower down in the geological
series we do not meet with more generalized (or ancestral) types; but
this is the difficulty number 3, which we now proceed to examine.
Concerning the other two difficulties, then, the only possible way of
meeting that as to the absence of any parent forms lower down in the
geological series is by falling back--as in the analogous case of
animals--upon the imperfection of the geological record. Although it is
certainly remarkable that we should not encounter any forms serving to
connect the Dicotyledonous plants of the Chalk with the lower forms of
the underlying Wealden, we must again remember that difficulties thus
depending on the absence of any corroborative record, are by no means
equivalent to what would have arisen in the presence of an adverse
record--such, for instance, as would have been exhibited had the floras
of the Wealden and the Chalk been inverted. But, as the case actually
stands, the mere fact that Dicotyledonous plants, where they first
occur, are found to have been already differentiated into their three
main divisions, is in itself sufficient evidence, on the general theory
of evolution, that there must be a break in the record as hitherto known
between the Wealden and the Chalk. Nor is it easy to see how the
opponents of this theory can prove their negative by furnishing evidence
to the contrary. And although such might justly be deemed an unfair way
of putting the matter, were this the only case where the geological
record is in evidence, it is not so when we remember that there are
numberless other cases where the geological record does testify to
connecting links in a most satisfactory manner. For in view of this
consideration the burden of proof is thrown upon those who point to
particular cases where there is thus a conspicuous absence of
transitional forms--the burden, namely, of proving that such cases are
not due merely to a break in the record. Besides, the break in the
record as regards this particular case may be apparent rather than real.
For I suppose there is no greater authority on the pure geology of the
subject than Sir Charles Lyell, and this is what he says of the
particular case in question. "If the passage seem at present to be
somewhat sudden from the flora of the Lower or Neocomian to that of the
Upper Cretaceous period, the abruptness of the change will probably
disappear when we are better acquainted with the fossil vegetation of
the uppermost tracts of the Neocomian and that of the lowest strata of
the Gault, or true Cretaceous series[59]."
[59] _Elements of Geology_, p. 280.
Lastly, the fact of the flora of the glacial epoch not having exhibited
any modifications during the long residence of some of its specific
types in Great Britain and elsewhere, is a fact of some importance to
the general theory of evolution, since it shows a higher degree of
stability on the part of these specific types than might perhaps have
been expected, supposing the theory to be true. But I do not see that
this constitutes a difficulty against the theory, when we have so many
other cases of proved transmutation to set against it. For instance, not
to go further afield than this very glacial flora itself, it will be
remembered that in an earlier chapter I selected it as furnishing
specially cogent proof of the transmutation of species. What, then, is
the explanation of so extraordinary a difference between Mr. Carruthers'
views and my own upon this point? I believe the explanation to be that
he does not take a sufficiently wide survey of the facts.
To begin with, it seems to me that he exaggerates the vicissitudes to
which the species of plants that he calls into evidence have been
exposed while advancing before, and retreating after, the ice. Rather do
I agree with Darwin that "they would not have been exposed during their
long migrations to any great diversity of temperature; and as they all
migrated in a body together, their mutual relations will not have been
much disturbed; hence, in accordance with the principles indicated in
this volume, these forms will not have been liable to much
modification[60]." But, be this matter of opinion as it may, a much
better test is afforded by those numerous cases all the world over,
where arctic species have been left stranded on alpine areas by the
retreat of glaciation; because here there is no room for differences of
opinion as to a "change of environment" having taken place. Not to speak
of climatic differences between arctic and alpine stations, consider
merely the changes which must have taken place in the relations of the
thus isolated species to each other, as well as to those of all the
foreign plants, insects, &c., with which they have long been thrown into
close association. If in _such_ cases no variation or transmutation had
taken place since the glacial epoch, then indeed there would have been a
difficulty of some magnitude. But, by parity of reasoning, whatever
degree of difficulty would have been thus presented is not merely
discharged, but converted into at least an equal degree of
corroboration, when it is found that under such circumstances, in
whatever part of the world they have occurred, some considerable amount
of variation and transmutation has always taken place,--and this in the
animals as well as in the plants. For instance, again to quote Darwin,
"If we compare the present Alpine plants and animals of the several
great European mountain-ranges one with another, though many of the
species remain identically the same, some exist as varieties, some as
doubtful forms or sub-species, and some as distinct yet closely allied
species representing each other on the several ranges[61]." Lastly, if
instead of considering the case of alpine floras, we take the much
larger case of the Old and New World as a whole, we meet with much
larger proofs of the same general facts. For, "during the slowly
decreasing warmth of the Pliocene period, as soon as the species in
common, which inhabited the New and Old Worlds, migrated south of the
Polar Circle, they will have been completely cut off from each other.
This separation, as far as the more temperate productions are concerned,
must have taken place long ages ago. As the plants and animals migrated
southward, they will have become mingled in one great region with the
native American productions, and would have had to compete with them;
and, in the other great region, with those of the Old World.
Consequently we have here everything favourable for much
modification,--for far more modification than with the Alpine
productions left isolated, within a much more recent period, on the
several mountain ranges and on the arctic lands of Europe and N.
America. Hence it has come, that when we compare the now living
productions of the temperate regions of the New and Old Worlds, we find
very few identical species; but we find in every class many forms, which
some naturalists rank as geographical races, and others as distinct
species; and a host of closely allied or representative forms which are
ranked by all naturalists as specifically distinct[62]."
[60] _Origin of Species_, p. 332.
[61] _Origin of Species_, p. 332.
[62] _Ibid_. pp. 333-4.
In view then of all the above considerations--and especially those
quoted from Darwin--it appears to me that far from raising any
difficulty against the theory of evolution, the facts adduced by Mr.
Carruthers make in favour of it. For when once these facts are taken in
connection with the others above mentioned, they serve to complete the
correspondence between degrees of modification with degrees of time on
the one hand, and with degrees of evolution, of change of environment,
&c., on the other. Or, in the words of Le Conte, when dealing with this
very subject, "It is impossible to conceive a more beautiful
illustration of the principles we have been trying to enforce[63]."
[63] _Evolution and its Relation to Religious Thought_, p. 194.
NOTE A TO PAGE 257.
The passages in Dr. Whewell's writings, to which allusion is here made,
are somewhat too long to be quoted in the text. But as I think they
deserved to be given, I will here reprint a letter which I wrote to
_Nature_ in March, 1888.
In his essay on the _Reception of the Origin of Species_, Prof.
Huxley writes:--
"It is interesting to observe that the possibility of a fifth
alternative, in addition to the four he has stated, has not dawned
upon Dr. Whewell's mind" (_Life and Lectures of Charles Darwin_,
vol. ii, p. 195).
And again, in the article _Science_, supplied to _The Reign of
Queen Victoria_, he says:--
"Whewell had not the slightest suspicion of Darwin's main theorem,
even as a logical possibility" (p 365).
Now, although it is true that no indication of such a logical
possibility is to be met with in the _History of the Inductive
Sciences_, there are several passages in the _Bridgewater Treatise_
which show a glimmering idea of such a possibility. Of these the
following are, perhaps, worth quoting. Speaking of the adaptation
of the period of flowering to the length of a year, he says:--
"Now such an adjustment must surely be accepted as a proof of
design, exercised in the formation of the world. Why should the
solar year be so long and no longer? or, this being such a length,
why should the vegetable cycle be exactly of the same length? Can
this be chance?... And, if not by chance, how otherwise could such
a coincidence occur than by an intentional adjustment of these two
things to one another; by a selection of such an organization in
plants as would fit them to the earth on which they were to grow;
by an adaptation of construction to conditions; of the scale of
construction to the scale of conditions? It cannot be accepted as
an explanation of this fact in the economy of plants, that it is
necessary to their existence; that no plants could possibly have
subsisted, and come down to us, except those which were thus
suited to their place on the earth. This is true; but it does not
at all remove the necessity of recurring to design as the origin of
the construction by which the existence and continuance of plants
is made possible. A watch could not go unless there were the most
exact adjustment in the forms and positions of its wheels; yet no
one would accept it as an explanation of the origin of such forms
and positions that the watch would not go if these were other than
they were. If the objector were to suppose that plants were
originally fitted to years of various lengths, and that such only
have survived to the present time as had a cycle of a length equal
to our present year, or one which could be accommodated to it, we
should reply that the assumption is too gratuitous and extravagant
to require much consideration."
Again, with regard to "the diurnal period," he adds:--
"Any supposition that the astronomical cycle has occasioned the
physiological one, that the structure of plants has been brought to
be what it is by the action of external causes, or that such plants
as could not accommodate themselves to the existing day have
perished, would be not only an arbitrary and baseless assumption,
but, moreover, useless for the purposes of explanation which it
professes, as we have noticed of a similar supposition with respect
to the annual cycle."
Of course these passages in no way make against Mr. Huxley's
allusions to Dr. Whewell's writings in proof that, until the
publication of the _Origin of Species_, the "main theorem" of this
work had not dawned on any other mind, save that of Mr. Wallace.
But these passages show, even more emphatically than total silence
with regard to the principle of survival could have done, the real
distance which at that time separated the minds of thinking men
from all that was wrapped up in this principle. For they show that
Dr. Whewell, even after he had obtained a glimpse of the principle
"as a logical possibility," only saw in it an "arbitrary and
baseless assumption." Moreover, the passages show a remarkable
juxtaposition of the very terms in which the theory of natural
selection was afterwards formulated. Indeed, if we strike out the
one word "intentional" (which conveys the preconceived idea of the
writer, and thus prevented him from doing justice to any
naturalistic view), all the following parts of the above quotations
might be supposed to have been written by a Darwinian. "If not by
chance, how otherwise could such a coincidence occur, than by an
_adjustment_ of these two things to one another; by a _selection_
of such an organization in plants as would _fit_ them to the earth
on which they were to grow; by an adaptation of _construction_ to
_conditions_; of the _scale_ of construction to the _scale_ of
conditions?" Yet he immediately goes on to say: "If the objector
were to suppose that plants were originally _fitted_ to years of
various lengths, and that such only have _survived_ to the present
time ... _as could be accommodated to it_ (i. e. the actual cycle),
we should reply that the assumption is too gratuitous and
extravagant to require much consideration." Was there ever a more
curious exhibition of failure to perceive the importance of a
"logical possibility"? And this at the very time when another mind
was bestowing twenty years of labour on its "consideration."
NOTE B TO PAGE 295.
Since these remarks were delivered in my lectures as here printed, Mr.
Mivart has alluded to the subject in the following and precisely
opposite sense:--
Many of the more noteworthy instincts lead us from manifestations
of purpose directed to the maintenance of the individual, to no
less plain manifestations of a purpose directed to the preservation
of the race. But a careful study of the interrelations and
interdependencies which exist between the various orders of
creatures inhabiting this planet shows us yet a more noteworthy
teleology--the existence of whole orders of such creatures being
directed to the service of other orders in various degrees of
subordination and augmentation respectively. This study reveals to
us, as a fact, the enchainment of all the various orders of
creatures in a hierarchy of activities, in harmony with what we
might expect to find in a world the outcome of a First Cause
possessed of intelligence and will[64].
[64] _On Truth_, p. 493.
Having read this much, a Darwinian is naturally led to expect that Mr.
Mivart is about to offer some examples of instincts or structures
exemplifying what in the margin he calls the "Hierarchy of
Ministrations." Yet the only facts he proceeds to adduce are the
sufficiently obvious facts, that the inorganic world existed before the
organic, plants before herbivorous animals, these before carnivorous,
and so on: that is to say, everywhere the conditions to the occurrence
of any given stage of evolution preceded such occurrence, as it is
obvious that they must, if, as of course it is not denied, the
possibility of such occurrence depended on the precedence of such
conditions. Now, it is surely obvious that such a "hierarchy of
ministrations" as this, far from telling against the theory of natural
selection, is the very thing which tells most in its favour. The fact
that animals, for instance, only appeared upon the earth after there
were plants for them to feed upon, is clearly a necessity of the case,
whether or not there was any design in the matter. Such "ministrations,"
therefore, as plant-organisms yield to animal-organisms is just the kind
of ministration that the theory of natural selection requires. Thus far,
then, both the theories--natural selection and super-natural
design--have an equal right to appropriate the facts. But now, if in no
one instance can it be shown that the ministration of plant-life to
animal-life is of such a kind as to subserve the interests of
animal-life without at the same time subserving those of the plant-life
itself, then the fact makes wholly in favour of the naturalistic
explanation of such ministration as appears. If any plants had presented
any characters pointing prospectively to needs of animals without
primarily ministering to their own, then, indeed, there would have been
no room for the theory of natural selection. But as this can nowhere be
alleged, the theory of natural selection finds all the facts to be
exactly as it requires them to be: such ministration as plants yield to
animals becomes so much evidence of natural selection having slowly
formed the animals to appropriate the nutrition which the plants had
previously gathered--and gathered under the previous influence of
natural selection acting on themselves entirely for their own sakes.
Therefore I say it is painfully manifest that "the enchainment of all
the various orders of creatures in a hierarchy of activities," is _not_
"in harmony with what we might expect to find in a world the outcome of
a First Cause possessed of intelligence and [beneficent] will." So far
as any argument from such "enchainment" reaches, it makes entirely
against the view which Mr. Mivart is advocating. In point of fact, there
is a total absence of any such "ministration" by one "order of
creatures" to the needs of any other order, as the beneficent design
theory would necessarily expect; while such ministration as actually
does obtain is exactly and universally the kind which the naturalistic
theory requires.
Again, quite independently, and still more recently, Mr. Mivart alluded
in _Nature_ (vol. xli, p. 41) to the difficulty which the apparently
exceptional case of gall-formation presents to the theory of natural
selection. Therefore I supplied (vol. xli, p. 80) the suggestion given
in the text, viz. that although it appears impossible that the sometimes
remarkably elaborate and adaptive structures of galls can be due to
natural selection acting directly on the plants themselves--seeing that
the adaptation has reference to the needs of their parasites--it is
quite possible that the phenomena may be due to natural selection acting
indirectly on the plants, by always preserving those individual insects
(and larvae) the character of whose secretions is such as will best
induce the particular shapes of galls that are required. Several other
correspondents took part in the discussion, and most of them accepted
the above explanation. Mr. T. D. A. Cockerell, however, advanced another
and very ingenious hypothesis, showing that there is certainly one
conceivable way in which natural selection might have produced all the
phenomena of gall-formation by acting directly on the plants
themselves[65]. Subsequently Mr. Cockerell published another paper upon
the subject, stating his views at greater length. The following is the
substance of his theory as there presented:--
[65] _Nature_, vol. xli, p. 344.
Doubtless there were internal plant-feeding larvae before there
were galls: and, indeed, we have geological evidence that boring
insects date very far back indeed. The primitive internal feeders,
then, were miners in the roots, stems, twigs, or leaves, such as
occur very commonly at the present day. These miners are
excessively harmful to plant-life, and form a class of the most
destructive insect-pests known to the farmer: they frequently cause
the death of the whole or part of the plant attacked. Now, we may
suppose that the secretions of certain of these insects caused a
swelling to appear where the larvae lived, and on this excrescence
the larvae fed. It is easy to see that the greater the excrescence,
and the greater the tendency of the larvae to feed upon it, instead
of destroying the vital tissues, the smaller is the amount of harm
to the plant. Now the continued life and vitality of the plant is
beneficial to the larvae, and the larger or more perfect the gall,
the greater the amount of available food. Hence natural selection
will have preserved and accumulated the gall-forming tendencies, as
not only beneficial to the larvae, but as a means whereby the
larvae can feed with least harm to the plant. So far from being
developed for the exclusive benefit of the larvae, it is easy to
see that, allowing a tendency to gall-formation, natural selection
would have developed galls exclusively for the benefit of the
plants, so that they might suffer a minimum of harm from the
unavoidable attacks of insects.
But here it may be questioned--have we proof that internal feeders
tend to form galls? In answer to this I would point out that
gall-formation is a peculiar feature, and cannot be expected to
arise in every group of internal feeders. But I think we can afford
sufficient proof that wherever it has arisen it has been preserved;
and further, that even the highly complex forms of galls are
evolved from forms so simple that we hesitate to call them galls at
all[66].
[66] _Entomologist_, March, 1890.
The paper then proceeds to give a number of individual cases. No doubt
the principal objection to which Mr. Cockerell's hypothesis is open is
one that was pointed out by Herr Wetterhan, viz. "the much greater
facility afforded to the indirect action through insects, by the
enormously more rapid succession of generations with the latter than
with many of their vegetable hosts--oaks above all[67]." This
difficulty, however, Mr. Cockerell believes maybe surmounted by the
consideration that a growing plant need not be regarded as a single
individual, but rather as an assemblage of such[68].
[67] _Nature_, vol. xli, p. 394.
[68] _Ibid._ vol. xli, pp. 559-560.
NOTE C TO PAGE 394.
The only remarks that Mr. Wallace has to offer on the _pattern of
colours_, as distinguished from a mere _brilliancy of colour_, are added
as an afterthought suggested to him by the late Mr. Alfred Tylor's book
on _Colouration of Animals and Plants_ (1886). But, in the first place,
it appears to me that Mr. Wallace has formed an altogether extravagant
estimate of the value of this work. For the object of the work is to
show, "that diversified colouration follows the chief lines of
structure, and changes at points, such as the joints, where function
changes." Now, in publishing this generalization, Mr. Tylor--who was not
a naturalist--took only a very limited view of the facts. When applied
to the animal kingdom as a whole, the theory is worthless; and even
within the limits of mammals, birds, and insects--which are the classes
to which Mr. Tylor mainly applies it--there are vastly more facts to
negative than to support it. This may be at once made apparent by the
following brief quotation from Prof. Lloyd Morgan:--
It can hardly be maintained that the theory affords us any adequate
explanation of the _specific_ colour-tints of the humming-birds, or
the pheasants, or the Papilionidae among butterflies. If, as Mr.
Wallace argues, the immense tufts of golden plumage in the bird of
paradise owe their origin to the fact that they are attached just
above the point where the arteries and nerves for the supply of the
pectoral muscles leave the interior of the body--and the
physiological rationale is not altogether obvious,--are there no
other birds in which similar arteries and nerves are found in a
similar position? Why have these no similar tufts? And why, in the
birds of paradise themselves, does it require four years ere these
nervous and arterial influences take effect upon the plumage?
Finally, one would inquire how the colour is determined and held
constant in each species. The difficulty of the Tylor-Wallace view,
even as a matter of origin, is especially great in those numerous
cases in which the colour is determined by delicate lines, thin
plates, or thin films of air or fluid. Mr. Poulton, who takes a
similar line of argument in his _Colours of Animals_ (p. 326), lays
special stress on the production of _white_ (pp. 201-202).
As regards the latter point, it may be noticed that not in any part of
his writings, so far as I can find, does Mr. Wallace allude to the
highly important fact of colours in animals being so largely due to
these purely physical causes. Everywhere he argues as if colours were
universally due to pigments; and in my opinion this unaccountable
oversight is the gravest defect in Mr. Wallace's treatment both of the
facts and the philosophy of colouration in the animal kingdom. For
instance, as regards the particular case of sexual colouration, the
oversight has prevented him from perceiving that his theory of
"brilliancy" as due to "a surplus of vital energy," is not so much as
logically possible in what must constitute at least one good half of the
facts to which he applies it--unless he shows that there is some
connection between vital energy and the development of striations,
imprisonment of air-bubbles, &c. But any such connection--so
essentially important for his theory--he does not even attempt to show.
Lastly, and quite apart from these remarkable oversights, even if Mr.
Tylor's hypothesis were as reasonable and well-sustained as it is
fanciful and inadequate, still it could not apply to _sexual_
colouration: it could apply only to colouration as affected by
physiological functions common to both sexes. Yet it is in order to
furnish a "preferable substitute" for Mr. Darwin's theory of _sexual_
colouration, that Mr. Wallace adduces the hypothesis in question as one
of "great weight"! In this matter, therefore, I entirely agree with
Poulton and Lloyd Morgan.
INDEX
A.
Accident, Darwin's use of the word, 334-340;
beauty due to, 408, 409.
Achromatin, 126-134.
Acquired characters, _see_ Characters.
_Acraea eurita_, 328.
Adaptation, facts of, in relation to theory of natural selection,
401-403, 411.
Adaptive characters, _see_ Characters.
AEsthetic sense in animals, 380-385;
_see_ Beautiful.
Agassiz, Prof. A., on fauna of the Mammoth cave, 70.
Alpine plants, 209, 210, 440-442.
_Amauris niavius_, 328.
_Amblyornis inornata_, 381-383.
_Amphioxus_, 137, 138, 145, 146.
Analogy, 38, 50-65, 176, 177, 347-350.
Anthropoid, _see_ Apes.
Antlers, 98-100, 167-169.
Ants, co-operative instincts of, 268;
leaf-cutting, 332;
keeping aphides, 292.
Ape, eye of, 75;
_appendix vermiformis_ of, 84-86.
Apes, ears of, compared with those of man, 88;
muscles of, 77, 82, 83;
feet of, 77, 78;
tail of, compared with that of man, 82-84;
hair of, compared with that of man, 89-91;
teeth of, compared with those of man, 92-94;
flattening of tibiae of, 95, 96.
Aphides, 292.
_Appendix vermiformis_ of man compared with that of orang, 84-86.
_Apteryx_, 68, 69.
_Archaeopteryx_, 171-173.
Arctic plants, 209, 210, 440-442.
Argyll, Duke of, on natural selection, 334-362.
Aristotle, his idea of scientific method, 1;
on classification, 23, 24.
Arm, distribution of hair on, in man and apes, 89-92.
_Arthropoda_, embryology of, 155.
Artificial selection, analogy of, to natural selection, 295-314;
pictorial representations of products of, 298-312.
Artiodactyls, 182-191.
Association, principle of, in aesthetics, 404-407.
Aster, 129-133.
Attraction-spheres, 128, 132, 133.
Australia, fauna of, 204, 205;
thriving of exotic species in, 286;
portrait of wild dog of, 304.
Azores, 224, 225.
B.
Bacon, Lord, on scientific method, 2.
_Balanoglossus_, 147, 148.
_Baptanodon discus_, posterior limb of, 179-181.
Barriers, in relation to geographical distribution, 216-224.
Bats, 56, 224, 226, 240.
Battle, law of, 385, 386.
Baya-bird, 381.
Bear, skeleton of, 174;
feet of, 178.
Beautiful, the, sense of, in animals, 380-385;
standards of, 380-404;
Darwin's explanation of, in organic nature, 379-411;
facts of, in inorganic nature in relation to Darwin's theory of, in
organic, 404;
often determined by natural selection, 406, 407;
absent in many plants and animals, 408;
in nature often accidental, 409-411;
does not exist in organic nature as an end _per se_, 410, 411.
Bees, co-operative instincts of, 268.
Beetles, wingless, 68-70;
on oceanic islands, 224, 226, 229, 232.
Bell, Dr., on natural theology, 412.
Bell-bird, 396-398.
_Bembidium_, 233.
Bermudas, 225-227.
Biology, ideas of method in, 1-9.
Birds, ovum of, 124;
embryology of, 151-155;
paleontology of, 163-165, 172, 173;
brain of, 194-197;
as carriers of seed, eggs, and small organisms, 217, 218;
distribution of, 224-240;
aesthetic sense of, 380-385;
courtship of, 380-385.
_Birgus latro_, 62-65.
Blood, colour of arterial, 409.
Boar, _see_ Pig.
_Bombus lapidarius_, 331.
Bower-birds, play-houses of, 381-383.
Boyd-Dawkins, on flattening of early human tibiae, 96.
Brain, palaeontology of, 194-197.
British Isles, _see_ Islands.
Broca, 363.
Bronn, 363.
Budding, _see_ Germination.
Burdon-Sanderson, Prof., on electric organ of skate, 366.
Butler, Bishop, on argument from ignorance, 41.
Butterflies, defensive colouring of, 321-329.
C.
Caesalpino, on classification, 24.
Calf, embryology of, 153.
Camel, foot of, 187-191.
Canadian stag, 196, 198, 199.
Canaries, portraits of, 303;
first mentioned by Gesner, 312, 313.
Cape de Verde Archipelagoes, fauna of, 228.
_Carcharias melanopterus_, 149.
Carruthers, on evolution, 436-442.
Caterpillars, colours and forms of, 319, 322-326.
Cattle, portraits of, 311.
Causation, natural, 402, 413, 414.
Caves, faunas of dark, 70-72.
Cell, physiological, and properties of the, 104-134.
_Cerura vinula_, 325, 326.
_Cervalces Americanus_, 196, 198, 199.
_Cervus dicrocerus_, _issiodorensis_, _matheronis_, _pardinensis_,
_Sedgwickii_, _tetraceros_, 168.
Chalmers, Dr., on natural theology, 412.
Chameleons, 317.
Characters, as adaptive, 273-276, 286-293, 349;
as specific, 274-276, 286-295;
as congenital and acquired, 274-276.
_Chasmorhynchus niveus_, and _C. tricarunculatus_, 396-398.
_Chelydra serpentina_, anterior limb of, 179-181.
Chick, embryology of, 153.
Chimpanzee, _see_ Apes.
Chlorophyll, 408.
_Chondracanthus cornutus_, 122.
Cirripedes, 430.
Classification, 23-49;
of organic nature by Genesis and Leviticus, 23;
artificial and natural, 24-26;
empirical rules of, 33-40;
Darwin on, 35, 36, 39,40;
form of, a nexus or tree, 29-32;
of organic forms like that of languages, 32;
single characters in relation to, 37;
aggregates of characters in relation to, 35-37;
adaptive and non-adaptive characters in relation to, 34, 35, 38, 39;
chains of affinities in relation to, 39-40;
biological differs from astronomical, 43.
Cockerell, on vegetable galls, 447, 448.
Colours, of plants and animals in relation to the theory of natural
selection, 317-332;
in relation to the theory of sexual selection, 391, 392, 394-396,
408-410, 448-450.
Colouring, _see_ Recognition marks, Protective, Seasonal, Warning, and
Mimicry.
Congenital characters, _see_ Characters.
Conjugation, of Protozoa, 115-117.
Continuity, principle of, in nature, 15-21.
Contrivance, Darwin's use of the word, 281.
Co-operation, mutual, of species alleged, 445-448.
Co-operative instincts, due to natural selection, 267, 269.
Cope, Professor, his table of geological formations, 163, 164;
his table of palaeontological development of feet, vertebral column, and
brain, 197.
Correlation of growth, 357-362.
_Cossonidae_, 233.
Courtship, _see_ Sexual Selection.
Crabs, 62-65, 139.
Cuttle-fish, 317.
Cuvier, on method in natural history, 3-4;
on monkeys, 429.
Cyst, _see_ Encystation.
D.
Darwin, Charles, his influence on ideas of method, 1-9;
on classification, 35, 36, 39, 40;
on vestigial characters in man, 77, 86, 87, 92;
on imperfection of geological record, 165, and Appendix;
on means of dispersal, 216, 218;
on geographical distribution, 218, 219;
on fauna of the Galapagos Archipelago, 227, 228;
on natural selection, 252, 253, 255, 256, 286, 375, 376;
his use of such words as 'accident,' 'fortuitous,' 'purpose,'
'contrivance,' &c., 281, 334-340;
on sexual selection, 379-400.
Darwin, Erasmus, his theory of evolution, 253.
De Blainville, on the theory of descent, 258.
De Candolle, on classification, 34.
Deer, 98, 99, 167-169, 187, 191, 196, 198, 199.
Degeneration, 269, 270, 342.
Delamination, 139.
_Diadema euryta_, 330.
Diaster, 129-133.
Dingo, _see_ Dog.
_Dinornis_, 60, 61.
_Diptera_ mimicking _Hymenoptera_, 329.
Dog, dentition of, 39;
Dingo, 304;
domesticated varieties of, 305, 307;
hairless, 307;
skulls of, 307.
Duck, logger-headed, 68.
Dugong, eye of, 75.
E.
Eagle, eye of, 75.
Ear, of whales, 65;
vestigial features of human, 76, 86-89;
of man and apes compared, 88.
Eaton, Rev. A. E., on wingless insects, 70.
_Echinodermata_, 125-127, 138, 155.
Ectoderm, 137-142.
Egg, _see_ Ovum.
Eimer, 363.
_Elaps fulvius_ imitated by non-venomous snakes, 330.
Electric organs, 365-373.
Elephant, foot of, 185, 186;
rate of propagation of, 261, 262.
Elk, 196-198, 199.
Embryo, human, _see_ Man.
Embryogeny, _see_ Ontogeny.
Embryology, 98-155.
Embryos, comparative series of, 152, 153.
_Encyclopaedia Britannica_, eighth ed., on instinct, 289-291.
Encystation of Protozoa, 115.
Endoderm, 137-142.
Equatorial plate, 129.
_Equus_, _see_ Horse.
_Erythrolamprus venustissimus_, 330.
Evolution, organic, fact of, Section I;
Method of, Section II;
ideas upon, prior to Darwin, 253-258;
divergent, 266, 267.
Ewart, Professor Cossar, on electric organ of skate, 364, 367.
Existence, _see_ Struggle for.
Eye, of octopus, 57, 58, 347-350;
absence of, in dark cave animals, 70-72;
nictitating membrane of, 74, 75;
development of, from cutaneous nerve-ending, 352-354.
F.
Feet, 51-59, 66, 77-80, 174-192, 197.
Fertilization of ova, 127, 128;
of flowers by insects, 406.
Fish, embryology of, 143-155;
palaeontology of, 163, 165, 169-171;
brain of, 194-197;
distribution of, 224-246;
flying, 355.
Fission, reproduction by, 106, 107.
Flat fish, 317.
Float, _see_ Swim-bladder.
Flowers, fertilization of, by insects, 406.
Fly, imitating a wasp, 329.
Flying-fish, and squirrels, 355.
_Foraminifera_, 346.
Forbes, H. O., on scapulo-coracoid bones of _Dinornis_, 60.
Fortuitous, Darwin's use of the word, 340.
Fossils, _see_ Palaeontology.
Frogs, 317.
G.
Galapagos Islands, 227-231, 236, 237.
_Galeus_, eye of, 75.
Galls, vegetable, 293-295, 446-448.
Gastraea, 137-140.
_Gastrophysema_, 138.
Gastrulation, 137, 140.
Gegenbaur, 147, 181.
Gemmation, reproduction by, 106, 107, 110, 111.
Generalization, 5.
Generalized types, 33.
Genesis, classification of organic nature in, 23.
Genial tubercle, 96.
Geographical distribution, 204-248;
_see_ Glacial period, Barriers Transport of organisms, Oceanic
islands, &c.
Geology, record of imperfect, 156-160, and Appendix;
_see_ Palaeontology.
Germs, prophetic, 272, 351-362.
Gesner, on classification, 24;
on canaries, 313.
Gill-arches, 146, 147, 150, 151.
Gill-slits, 146, 147, 150-153.
Gills, of young salamanders, 102;
origin of, in embryo, 144;
of fish, 150, 152.
Giraffe, neck of, in relation to Lamarck's theory, 254.
Glacial periods, effects of, on distribution of plants and animals,
209, 210, and Appendix.
Goose, Frizzled, portrait of, 304.
Gorilla, _see_ Apes.
Gray, Professor Asa, 337
Great-toe, in man and apes, 79-81.
Grouse, 317-319
Growth, correlation of, 357, 362.
_Gymnotus_, 365, 367.
H.
Haeckel, on analogy between species and languages, 32;
on reproduction as discontinuous growth, 105, 106;
his ideal primitive vertebrate, 143, 144.
Hair, vestigial characters of, in man, 89-92.
Hales, 3.
Haller, 3.
Hamilton, Sir William, 272.
Hands, 51-55, 66, 80-82, 174-192.
Hare, 318, 319.
Hartmann, on flattening of early human tibiae, 96.
Harvey, on Lord Bacon's writings, 2.
Heart, development of, 154.
Heilprin, on skulls of deer, 198, 199;
on fossil shells, 201, 202.
Hen, ovum of, 122.
Heredity, in relation to classification, 28-31;
in relation to embryology, 98-102;
chromatin-fibres in relation to, 134;
in relation to theories of organic evolution, 253-255, 260-264, 377.
Hermit-crabs, 62-65, 288, 289.
_Heteromera_, 233.
Hilgendorf, on shells of _Planorbis_, 201.
_Hipparion_, 191, 192.
Hippopotamus, foot of, 187.
Hog, _see_ Pig.
Homology, 38, 50-65, 176, 177, 347-350, 357-359.
Homopterous insect, imitating leaf-cutting ants, 331, 332.
Hooker, Sir Joseph, on flora of St. Helena, 234.
Horns, 98-100, 167-169.
Horse, eye of, 75;
limb-bones of, 176, 177, 186, 188-192;
teeth of, 189-191;
portraits of domesticated breeds of, 309.
Human, _see_ Man.
_Humerus_, perforations of, in quadrumana and man, 94, 95.
Humming-birds, restricted to the New World, 211.
Hunter, 3;
on ear of whale, 65.
Huxley, Prof., on mechanical selection, 283;
on age of the earth, 435, 436;
on Dr. Whewell, 243.
Hyatt, on shells of _Planorbis_, 201.
_Hydra_, 111, 122.
_Hyrax_, foot of, 185, 186.
I.
Ignorance, argument from, 41, 42, 49.
Illative Sense, 6.
Imitative colours, 317-323, 326-332.
Infant, feet of, 78, 79;
grasping power of, 81.
Infertility, inter-specific, in relation to natural selection, 374-376.
Insects, wingless, 68-70;
in primary formations, 163, Appendix;
on oceanic islands, 224-238;
in relation to galls, 293-295, 446-448;
defensive colouring of, 321-332;
fertilizing flowers, 406.
Instincts, always of primary use to species presenting them, 286-293.
Intercrossing, in relation to natural selection, 374-376.
Inutility of specific characters, in relation to natural selection,
374-376.
Islands, oceanic, 224-237;
British, 238-241.
J.
Japan, hairless dog of, 101.
Jelly-fish, 119, 120.
K.
_Kallima_, 323.
Karyokinesis, 112-114, 128-134.
Kepler, 272.
Kerguelen Island, flightless insects of, 70.
Kropotkin, Prince, on co-operative instincts, 269.
L.
_Lagopus mutus_, 317, 318.
Lamarck, his method in natural history, 4;
his theory of evolution, 253-256.
Lamprey, 148.
Languages, classification of, resembles that of organic forms, 32.
Lankester, E. Ray, on karyokinesis, 129, 130.
Leaf insect, 322.
Le Conte, on geological succession of animal classes, 164, 165;
on types of tails, 169-173;
on fossil shells of _Planorbis_, 201;
his work on the relation of the theory of evolution to religious
thought, 412.
_Leptalis_, 328.
_Leuculmis echinus_, 122.
Leviticus, classification of organic nature in, 23.
Life, origin of, 15.
Linnaeus, on method in natural history, 3;
on classification, 26, 35-40.
Lion, skeleton of, 175;
feet of, 178.
Lizard, heart and gill-arches of, 150.
Lloyd Morgan, 273, 449, 450.
Lungs, development of, 154, 354.
Lyell, Sir Charles, on classification, 32;
on uniformitarianism, 258;
on rational species, 344;
on geological record, 420, 435, 439.
M.
Madeira, wingless beetles of, 68-70;
peculiar beetles of, 226, 227.
Mammals, ovum of, 120-124;
embryology of, 151-155;
palaeontology of, 163, 165, 167, 180-199;
limbs of, 174-178, 182-199;
brain of, 194-199;
of Australia and New Zealand, 204, 205;
distribution of, on islands, 224-240.
Mammoth cave, fauna of, 70-72.
Man, nictitating membrane of, 75;
vestigial muscles of, 76, 77, 82, 83;
tail of, compared with that of apes, 82-84;
hair of, compared with that of apes, 89-92;
teeth of, compared with those of apes, 92-94;
perforation of humerus of, 94, 95;
flattening of ancient tibiae of, 95, 96;
embryology of, 119, 153;
hand of, 54;
arm of, 90, 91;
limb-bones of, 176, 177;
palaeontology of, 163, 165;
brain of, 194, 195;
Mr. Syme on, 346, 347.
Marsh, on palaeontology of the horse, 188-190.
Matthew, Patrick, on natural selection, 257.
Mesoderm, 142.
_Mesohippus_, 189, 192.
Metaphyta, 104, 105.
Metazoa, 104.
Method, ideas of, in natural history, 1-9;
of organic evolution, 252-261.
Meyer, Professor Ludwig, on helix of the human ear, 86.
Mimicry, 320-322.
Ministration, mutual, of species alleged, 445, 446.
_Miohippus_, 189.
Mivart, St. George, on eye of octopus, 57, 58, 348, 349;
on incipient organs, 362;
on mutual ministration of species, 445, 446.
Mollusca, shells of, 19, 199-203;
eye of, 57, 58;
embryology of, 155;
palaeontology of, 163, 165.
Monkeys, why all, do not become men, 342-344.
_Monotremata_, 205.
Morgan, _see_ Lloyd Morgan.
Morphology, 50-97.
Mule, portrait of, 309.
Multicellular organisms, 104.
Multiplication, _see_ Reproduction.
N.
Naegeli, Prof., 337, 367.
Natural History, ideas of method in, 1-9.
Natural, interpretations as opposed to super-natural, 13-15;
causation, 13-15.
Natural selection, 252-378, 401-410;
Wells, Matthew, and Whewell on, 257, 258, 443-445;
statement of theory of, 256-284;
of evidences of, 285-332;
of criticisms of, 333-378;
relation of theory of, to religious thought, 401-410;
preserves types, 264-267;
cessation and reversal of, 270, 342;
errors touching theory of, 270-284, 332-364;
definition of, 275-376;
antecedent standing of theory of, 277-284;
Prof. Owen on, 333, 334;
Duke of Argyll on, 334-362;
Mr. Syme on, 340, 341, 345;
need not always make for improvement, 341-347;
homology and analogy in relation to, 347-350;
often determines beauty, 406, 407;
in relation to the formation of galls, 293-295. 446-448.
Nature, organic, 17;
inorganic, 1, 17, 18.
_Nauplius_, 138.
Neumayr, 19.
New Zealand, fauna of, 68, 204, 205;
thriving of exotic species in, 286.
Newman, on the Illative Sense, 6.
Newton, his idea of scientific method, 6.
Nictitating membrane, 74, 75.
Notochord, 146.
Novum Organon, the, on scientific method, 2.
Nucleus, 105, 112-134.
Nucleus-spindle, 129.
Nut-hatch, Syrian, ornamented nests of, 381.
O.
Objective methods, 6.
Oceanic islands, _see_ Islands.
Octopus, eye of, 57, 58, 348-350.
_[OE]dicnemus crepitans_, 320.
Ontogeny, as recapitulation of phylogeny, 98-104.
Orang Outang, _see_ Apes.
_Oredon Culbertsoni_, 167.
Origin of Species, the, influence exercised by, on ideas of method, 1-9
_Orohippus_, 189.
Otaria, eye of, 75.
Ovum, 113-142;
human, 120-133;
amoeboid movements of young, 121-123;
segmentation of, 134, 135.
Owen, on ear of whale, 65;
on natural selection, 333, 334.
Owl, eye of, 75.
P.
Paddle, _see_ Whale, and _Baptanodon discus_.
_Pagurus bernhardus_, 64.
Pain, in relation to the theory of evolution, 417.
Palaeontology, 159-203;
general testimony of, 156-165;
testimony of, in particular cases, 165-203;
consideration of objections to theory of evolution founded on grounds
of, 156-165, and Appendix.
_Palaeotherium_, 190, 191.
Paley, on natural theology, 98, 412.
_Paludina_, successive forms of, 19.
Panama, Isthmus of, 219.
_Panniculus carnosis_, 77.
_Papilio merope_, 330.
Parasites, of animals, devoid of beauty, 408.
Parsimony, law of, 272.
Parthenogenesis, 119.
Partridges, 319.
Peacock, tail of, 378;
courtship of, 383.
Peckham, Mr. and Mrs., on courtship of spiders, 388-390.
Perissodactyls, 182-192.
_Petromyzon marinus_, 148.
_Phenacodus primaevus_, 184, 185.
Phylogeny, _see_ Ontogeny.
Physiological selection, 376.
Pig, embryology of, 153;
feet of, 176, 187;
portraits of wild and domesticated, 312.
Pigeons, portraits of, 298, 299;
feather-footed, 359.
Pilot fish, 289.
_Planorbis_, transmutations of, 200, 201.
Pleasure and pain, in relation to the theory of evolution, 417.
_Plica semilunaris_, 75.
_Pliohippus_, 189.
Polar bear, skeleton of, 174;
feet of, 178.
Polar bodies, 125, 126.
Polar star, 129.
Polyps, 114.
Porpoises, 24, 25, 50.
Poulton, E. B., on warning colours, 325, 326;
on mimicry, 331, 332;
sexual selection, 400, 401, 449, 450.
Poultry, portraits of, 300-302.
Pronucleus, 126-128.
Prophetic types, 272, 351-362.
_Prophysema primordiale_, 140.
Protective colouring, 317-323.
_Protohippus_, 189.
Protozoa, 104.
Ptarmigan, 317, 318.
_Pterodactyl_, wing of, 56.
Purpose, Darwin's use of the word, 281, 340.
Puss moth, larva of, 325, 326.
Python, 66, 67.
Q.
Quadrumana, muscles of, 76, 82, 83;
perforations of humeri of, 94, 95;
hair on phalanges of, 91.
R.
Rabbit, embryology of, 153;
multiplication of, in Australia, 286;
portraits of wild and domesticated breeds of, 308;
protective colouring of, 319, 320.
Radiate form, beauty of, 408, 409.
_Raia radiata_, and _batis_, 367-371.
Rats, species of, restricted to Old and New Worlds, 212;
British and Norwegian, 285, 286.
Rattle-snake, tail of, 289.
Recognition marks, 271-273.
Religion, in relation to Darwinism, 401-418.
Reproduction, different methods of, 106-117;
essence of sexual, 110;
foreshadowing of sexual in unicellular organisms, 115-117.
Reptiles, wing of flying, 56;
rudimentary limbs of, 67;
nictitating membrane of, 75;
branchial arches of, 150;
embryology of, 152;
palaeontology of, 163, 165, 178-180;
brain of, 194-197;
distribution of, 224-240.
_Rhinoceros_, foot of, 186.
Robinson, Dr L., on grasping power of an infant's hands, 80-82.
Rudimentary organs, 65-97.
Ruminants, palaeontology of, 167, 168.
S.
Sacrum of man, compared with that of apes, 82-84.
_Sagitta_, 138.
Salamander, young of terrestrial, living in water, 102;
embryology of, 152.
Sandwich Islands, 234-237.
Science, method of, 1-9.
Sclater, W. L., on a case of mimicry, 331, 332.
Scorpion in Silurian formation, 163.
Sea, lamprey, 148;
destructive agency of the, 423, 424.
Seal, 51, 52, 75.
Seasonal changes of colour, 317-319.
Selection, value, 275;
by physical processes, 282, 283, 335. _See also_ Natural selection,
Artificial selection, Sexual selection, Physiological selection.
Sentiency, in relation to the theory of evolution, 417.
Sex, difference of, restricted to Metazoa and Metaphyta, 105.
Sexual reproduction, _see_ Reproduction.
Sexual selection, theory of, 277, 378-410;
statement and evidences of, 379-391;
criticisms of, 391-400;
includes law of battle with that of charming, 385, 386;
in relation to religious thought, 411-418;
Tylor's theory substituted for, by Wallace, 449, 450.
Shark, eye of, 75;
man-eating, 149;
and pilot-fish, 289.
Sheep, limb-bones of, 176, 177;
portraits of, 310.
Shells, of crabs, 62-64;
palaeontology of mollusks, 199-203;
land on oceanic islands, 224-240.
Silliman's Journal, on fauna of the Mammoth Cave, 70.
Skate, electric organ of, 364-373.
Skull, palaeontology of, 194-199;
of bull-dog compared with that of deer-hound, 307.
Slavonia, Tertiary deposits of, 18, 19.
Species, not eternal, but either created or evolved, 13;
named as such through absence of intermediate forms, 18-20;
groups of, in classification, 20,
and appearing suddenly in geological formations, 427-432, 437-440;
origin of, coincide in space and time with pre-existing and allied
species, 22;
geographical distribution of, 204-248;
extinct and living allied on same areas, 213;
life of, preserved by natural selection, 264-270;
not room for more than one rational, 344;
characters of, 274-276, 286-295, 374-376;
inter-sterility of allied, 374-376;
mutual ministration of alleged, 445, 446.
Specific characters, _see_ Characters.
Speculation, method of, 3-9.
Spencer, Herbert, on reproduction as discontinuous growth, 105, 106;
on use-inheritance, 253-256;
his failure to conceive the idea of natural selection, 257.
Spermatozoa, 123, 126-128.
Spiders, in primary formations, 163;
courtship of, 388, 389.
Sponges, 122, 139, 140.
Spontaneous, Darwin's use of the term, 340.
Spores, 115.
Squirrels, flying, 355.
Sterility, _see_ Infertility.
St. Helena, 231-234, 236-237.
St. Hilaire, 4.
Stick-insect, 322.
Stoat, 318.
_Strombus accipilrinus_, 201.
_Strombus Leidy_, 201.
Struggle for existence, 259-270.
Subjective, methods, 6.
Survival of the fittest, 335. _See also_ Natural selection.
Swim-bladder of fish, 154, 354.
Symbiosis, 269.
Syme, David, on the theory of natural selection, 340, 341.
T.
Tail, types of, in fish and birds, 169-173.
Tasmanian wolf, dentition of, 39.
Teeth, of Tasmanian wolf, 39;
molar, of man, compared with those of apes, 92-94;
palaeontology of horses', 189-191.
Temperature, sense of, probable origin of that of sight, 353, 354.
Tennyson, 266.
Tibiae, flattening of, 95, 96.
Tissue-cells, _see_ Cell.
Toes, 79, 80; _see also_ Feet.
Tomes, C. S., on molar teeth of man and apes, 94.
_Torpedo_, 365, 367.
Tortoise, embryology of, 152, 154.
_Toxopneustes variegatus_, and _T. lividus_, 122.
Transport of organisms, means of, 207, 216-218.
Tribal fitness, as distinguished from individual, 267-269.
Trout, ovum of, 122.
Turtle, eye of, 75.
Tylor, Alfred, on colouration of animals, 448-450.
Type, preserved by natural selection, 264-269;
improvement of, by natural selection, 269, 270;
prophetic, 272, 351-362.
Types, as simple and generalized, 33.
U.
Unicellular organisms, 104.
_Uraster_, 138.
Utility, of specific characters, 274, 275;
of incipient characters, 351-363;
of electric organs, 365-373.
V.
Variation, in relation to natural selection, 263, 335-340, 377.
Verification, 6-9.
Vertebral column, embryology of 145, 146;
palaeontology of, 192, 193.
Vertebrated animal, ideal primitive, 143, 144;
embryology of, 143, 155.
_Vespa vulgaris_, 331.
Vestigial organs, 65-97.
_Volucella inans_, and _V. bombylans_, 329.
W.
Wagner, Moritz, on geographical distribution, 216.
Wallace, A. R., on origin of species as coincident in time and space
with pre-existing and allied species, 22;
on wingless insects, 70;
on absence of hair from human back, and function of on arms of
orang, 89;
on geographical distribution, 207, 231, 232, 233, 243;
on natural selection, 256;
on recognition marks, 271-273;
on alleged deductive consequences of the natural selection theory,
273-276;
his theory of warning colours, 323, 324;
on sexual selection, 391-400, 450;
his principal defect in treating of animal colouration, 449, 450.
Warning colours, 323-326.
Wasp, imitated by a fly, 329.
Water-cress, multiplication of, in New Zealand, 286.
Weevils, on St. Helena, 232.
Weismann, his theory of heredity, 130, 134.
Wells, Dr., on natural selection, 257.
Wetterhan, Prof., on vegetable galls, 448.
Whales, 38, 50, 53, 54, 65, 180.
Whewell, on natural selection, 257, 258, 443-445.
Wings, 54-56, 60, 61, 68-70, 355.
Wolf, Tasmanian, dentition of, 34.
Wood, John, on vestigial muscles in man, 77.
Woodward, on fossil cirripedes, 431.
Woolner, on the human ear, 86.
Worms, embryology of, 155.
Wyman, Prof., on the great toe of human embryo, 79, 80.
Z.
_Zona pellucida_, 121.
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| |
| Transcriber's Notes and Errata |
| |
| The following words were found in both hyphenated and |
| unhyphenated forms in the text. The number of instances is |
| given in parentheses after each word. |
| |
| |deer-hound (2) |deerhound (1) | |
| |fresh-water (13) |freshwater (1) | |
| |inter-relations (1) |interrelations (1) | |
| |re-action (1) |reaction (1) | |
| |sea-weed (7) |seaweed (1) | |
| |super-natural (2) |supernatural (24) | |
| |wood-cut (3) |woodcut (3) | |
| |wood-cuts (4) |woodcuts (1) | |
| |
| There were 9 instances of 'larvae' and 3 instances of |
| 'larvae'. |
| |
| The following typographical errors were corrected: |
| |
| |Error |Correction | |
| | | | |
| |arboresent |arborescent | |
| |the |The | |
| |dicussion |discussion | |
| |
| In the index, the page entry for "Lyell, Sir Charles ... on |
| geological record" was changed from '420' to '422'. |
| |
| Also, the page entry for "Natural selection ... definition |
| of" was changed from '275-376' to '275-276'. |
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