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implies, has a sandy-brown back, which contrasts

378



Local Species

strongly with the glossy black of his head, neck,
and under parts. In summer the cocks of the
two species grow more like one another owing to
the wearing away of the outer edges of their
feathers ; but it is always possible to distinguish
between them at a glance. The two species
meet at about the latitude of Bombay. Gates
states that in a certain zone, from Ahmednagar
to the mouth of the Godaveri valley, both
species occur, and they do not appear to
interbreed.

It seems impossible to maintain that natural
selection, acting on minute variations, has
brought about the divergence between these
two species. Even if it be asserted that the
difference in the colour of the feathers of the
back of the two cocks is in some way correlated
with adaptability to their particular environment,
how are we to explain the fact that in a certain
zone both species flourish ?

" A similar phenomenon is furnished by the
red-vented bulbul. This genus falls into several
species, each corresponding to a definite locality
and differing only in details from the allied
species, as, for example, the distance down the
neck to which the black of the head extends.
There is a Punjab Red-vented Bulbul (Molpastes
intermedius], a Bengal {Molpastes bengalensis), a
Burmese {Molpastes burmanicus], and a Madras
(Molpastes hcemorrhous) species.

379



The Making of Species

"It does not seem possible to maintain the
contention that these various species are the
products of natural selection, for that would
mean if the black of the head of the Punjab
species extended further into the neck the bird
could not live in that country."

Thus, natural selection clearly is unable to
explain some cases of divergence of character
due to geographical isolation.

There remains the third explanation, that the
divergence is the result of the simple fact of
isolation.

We have already shown how insuperable are
the objections to the view held by Romanes and
Gulick.

It seems to us that explanation must lie in the
fact that mutations occur every now and again in
some species. If two portions of a species are
separated and a mutation occurs in one portion
and not in the other, and if the mutating form
succeeds in supplanting the parent form in that
isolated portion of the species in which it has
appeared, we should have the phenomenon of
two races or species differing in appearance
although subjected to what appear to be identical
environment.

This, of course, is pure conjecture. All that
can be said of it at present is that it is not
opposed to observed facts. That mutations do
occur must be admitted. At present we are

380



Cormorants

totally in the dark as to what causes them.
They arise at the most unexpected times.

In favour of the explanation based on " muta-
tion " there is the interesting fact that geographi-
cal isolation does not by any means always cause
divergence of character. This Romanes, with
great fairness, freely admits. " There are/' he
writes, on p. 133 of vol. iii. of Darwin and
after Darwin, " four species of butterflies, belong-
ing to three genera (Lyccena donzelii, L.pheretes,
Argynnis pales, Erebia manto\ which are iden-
tical in the polar regions and the Alps, notwith-
standing that the sparse Alpine populations have
been presumably separated from their parent
stocks since the glacial period." Again, there
are "certain species of fresh- water crustaceans
(Apus), the representatives of which are com-
pelled habitually to form small isolated colonies
in widely separated ponds, and nevertheless
exhibit no divergence of character, although
apogamy has probably lasted for centuries."

To these examples we may add that of the
cormorants. These birds have an almost world-
wide range. One species our Cormorant
(Pkalacrocorax carbo] occurs in every imagin-
able kind of environment. Isolation has not
effected any changes in the appearance of this
species. Yet in New Zealand there exist no
fewer than fourteen other species of cormorant.
New Zealand is a country where climatic con-

381



The Making of Species

ditions are comparatively uniform, nevertheless
it boasts of no fewer than fifteen out of the thirty-
seven known species of cormorant. A possible
explanation of this phenomenon may be found
in the comparatively easy conditions under which
cormorants live in New Zealand. 1 Under such
circumstances mutants may be permitted by
natural selection to survive, whereas in other
parts of the world such mutants have not been
able to hold their own.

Prof. Bateson has likened natural selection
to a competitive examination to which every
organism must submit. The penalty for failure
is immediate death. The standard of the ex-
amination may vary with the locality.

Isolation, then, is a very important factor in
the making of species, for without it, in some
form, the multiplication of species is impossible.

Let us, in conclusion, briefly summarise what
we now know of the method in which new species
are made. We have studied the various factors
of evolution variation and correlation, heredity,
natural selection, sexual selection, and the other
kinds of isolation. How do these combine to bring
new species into being, and to establish the same ?

Let us first consider the factor known as
natural selection, since this is the one on which

1 Hutton and Drummond record other examples of this in the
valuable work entitled The Animals of New Zealand.

382



Natural Selection

Darwin laid such great stress. Natural selection,
although a most important factor in evolution, is
not an indispensable one. Evolution is possible
without natural selection.

Let us suppose that there is no such thing as
natural selection ; that the numbers of existing
species are kept constant by the elimination of
all individuals born in excess of the number
required to maintain the species at the existing
figure, and that the elimination of the surplus is
effected, not by natural selection, but by chance,
by the drawing of lots. Under such circum-
stances there may be evolution, existing species
may undergo change, but the evolution will be
determined solely by the lines along which
variations occur.

If mutations take place along certain fixed
lines, and tend to accumulate in the given
directions, evolution will proceed along these
lines quite independently of the utility to the
organism of the mutations that occur. An un-
favourable mutation will have precisely the same
chance of survival as a favourable one.

If, on the other hand, mutations occur in-
discriminately on all sides of the mean, then
those mutations which happen to occur most
frequently will have the best chance of survival,
and they will mark the lines of evolution. But
suppose that no mutation occurs more frequently
than the others. Under such circumstances there

383



The Making of Species

will be no evolution, unless, by some cause or
other, portions of the species are isolated, because
in the long run the mutations will neutralise one
another.

Let us now suppose that natural selection
comes into play. The old method of determining
by lot which forms shall persist is replaced by
selection on the fixed principle that the fittest
shall survive. The mutations appear as before,
and as before, of the large number that occur,
only a few are permitted to survive. But now
the survivors, instead of being a motley crowd,
are a selected band, composed of individuals
having many characteristics in common a
homogeneous company. Thus one result of
natural selection is to accelerate evolution, by
weeding out certain classes of individuals and
preventing them breeding with those it has
selected. On the other hand, natural selection
will tend to diminish the number of species which
have arisen through mutation, inasmuch as it
weeds out many mutants which would have
perished had their survival been determined by
lot

From this the kind of work performed by
natural selection should be obvious. Natural
selection does not make new species. These
make themselves, or, rather, originate in accord-
ance with the laws of variation.

"You can," runs an old proverb, " bring a
384



Natural Selection

horse to the drinking fountain, but you cannot
make him drink." You may be able to bring a
child into the world, but you cannot secure its
survival. Variation brings into being mutants,
which are incipient species, but variation cannot
determine their survival. It is at this stage that
natural selection steps in.

But because natural selection allows certain
mutations to persist, it is not correct to say that
natural selection has caused these mutations or
made or originated the species to which they give
rise.

The Civil Service Commissioners do not make
Indian civil servants : they merely determine
which of a number of ready-made men shall
become civil servants. Similarly, natural selec-
tion does not make new species, it simply decides
which of a number of ready-made organisms shall
survive and establish themselves as new species.
Nor does natural selection always do as much as
this ; for it is not the only determinant of survival.
Its position is sometimes comparable to that of
the Medical Board which inspects and rejects
the physically unfit of the candidates which have
already been selected by some other authority.

The examination conducted by natural selec-
tion may be compared to a competitive one. A
separate, independent examination is held for
each particular locality ; consequently the severity
of the competition will vary with the locality.
2B 385



The Making of Species

In each competition some candidates pass with
ease : they gain an unnecessarily high total of
marks. So in nature do certain organisms, as,
for example, the Leaf-butterflies (Kallimas),
appear to be over-adapted to their environment.
Other candidates manage to pass only by a very
narrow margin : these are paralleled in nature by
those species which are barely able to maintain
themselves, which become extinct the moment
the competition increases in severity.

The great bulk of the candidates fail to obtain
sufficient marks to gain a place among the chosen
few ; these unsuccessful candidates correspond to
the mutating forms which perish in the struggle
for existence, to those individuals which happen
to have mutated in unfavourable directions.

Even as many candidates have acquired know-
ledge of subjects in which they are not examined,
so do many organisms possess characteristics
which are of no utility to them in the struggle
for existence.

Wallaceians expend much time and energy in
misguided attempts to explain the existence of
such characters in terms of natural selection.

Nature's examination, like that held for en-
trance to the Indian Civil Service, is a liberal
one, so that the qualifications of the successful
candidates vary considerably. Provided a can-
didate is able to gain more marks than the other
candidates for a vacancy, it matters not in what

386



Origin of the Fittest

subjects the marks are gained. So is it in nature.
Natural selection takes an organism as a whole.
One species may have established itself because
of its fleetness, a second because of its courage,
a third because it has a strong constitution, a
fourth because it is protectively coloured, a fifth
because it has good digestive powers, and so on.

We thus perceive the part played by natural
selection and other forms of isolation in the
making of species. It is obvious that these
do not make species any more than the Civil
Service Commissioners manufacture Indian civil
servants.

The real makers of species are the inherent
properties of protoplasm and the laws of variation
and heredity. These determine the nature of the
organism ; natural selection and the like factors
merely decide for each particular organism whether
it shall survive and give rise to a species.

The way in which natural selection does its
work is comparatively easy to understand. But
this is only the fringe of the territory which we
call evolution.

We seem to be tolerably near a solution of
the problem of the causes of the survival of
any particular mutation. This, however, is
merely a side issue. The real problem is the
cause of variations and mutations, or, in other
words, how species originate. At present our
knowledge of the causes of variation and muta-

387



The Making of Species

tion is practically nil. We do not even know
along what particular lines mutations occur.

We have yet to discover whether one mutation
invariably leads to another along the same lines
in other words, whether mutating organisms
behave as though they had behind them a force
acting in a definite direction. The solution of
these problems seems afar off. The hope of
solving them lies, not in the speculations in
which biologists of to-day are so fond of in-
dulging, but in observation and experiment,
especially the last.

The future of biology is largely in the hands
of the practical breeder.



388



INDEX



ACCENTOR, i

Accipitcr cooperi, 243

Acorn, 49

Acquired characters, 10, 14, 15, 18-
24, 60, 107-10

Acrceidce, 175, 215, 228

j&gilops speltceformiS) 118

j&githina tiphia, 244

^Esthetic sense in birds, 306

"African Nature Notes and Re-
miniscences," 192, 195, 199

Aggressive resemblance, 173

Aguara-guazu, 181

Aitken, E. H., 64

"Albany Review, The," 43, 48,
195, 204

Albinism, 64, 65, 99, 283, 284, 362

Alcedo ispida, 289

Alcock, Col., 216, 217

Alcohol, 152, 153

Alexander, 181

Allen, Grant, 66

Allotrophy, 159

Alternating characters, 143

Alternative inheritance, 127

Amadavat, 311

Amandina crythrocephala, 122

A.fasciata, 122

" Amazement," 93

Amazon parrot, 103

Amazonian dolphin, 99

Ammonites, 67

Ammonium sulphate, 151

Amoeba, 35

Auiphidasys betularia, 101

Anas boscas, 123, 334

A. obscura, 334

A. pacilorhyncha, 315, 334

A. superciliosa, 315, 334

A. undulata, 334

Anastomus oscitans, 282

Ancon sheep, 95

Anemone magellanica, 118

A. sylvestris, 118

Anemophilous flowers, 261

"Animal Colouration," 194, 205,

211, 213, 2l8, 222

" Animal Life and Intelligence,"



368



"Animals of New Zealand," 382

Anous, 278

Anser cygnoides, 1 14

Anseranas melanoleucus ', 281

Antarctic fauna, 191

Antelope, 48, 199, 334

Anthracoceros, 220

Anthropoides paradisea, 279

A. virgo, 279

Antilope cervicapra, 363

Ape, 101

Apogamy, 370

Appenzeller, 340

t 381

Archiv fiir Entwicklungs-
mechanik der Organismen,"

3 2 S 330

Arctic fauna, 173, 174, 190, 19^
Arctic regions, 173, 189
Ardea asha, 317, 318
A. gularis, 318
Ardeola grayii, 250, 254
Argali, 120, 130, 131
" Argentine Ornithology," 361
Argynnis pales, 381
A. paphia, 103
Aristotle, I

Artcmia iiiilhausenii, 156
A. salina, 156
Aseel, 364

Asexual reproduction, 135
Asiatic, 140
Ass, 117, 127, 128, 140
Astur badius, 235
Atavism, 136, 293
Athene chiaradic y 97
A. noctua, 97
Atoms, biological, 158
"Auk, The," 190
Aularches militaris, 216
Avebury, Lord, 205, 260
" Avicultural Magazine, The," 98
Avocet, 80

BABBLER, 244
Bactrian camel, 1 21
Bailey, 88
Baillon's crake, 251



Balanced characters, 143
389



The Making of Species



Balearica chrysopelargus, 105

B. regulorum, 105

Bassaris astuta, 242

Batesian mimicry, 177

Bateson, 26, 72, 73, 74, 75, 76,

102, 103, 302
Bats, 42

Bear, 101, 119, 190, 216, 282
Beddard, 180, 188, 194, 205, 21 1
Bee, 178, 179, 214, 221, 263, 264,

269

Beech, purple, 87
Bee-eater, 220, 278
Beetroots, 71
Belt, 216
Beluga, 190
Bentham, 260
Bestiary, 125
Bicheno's finch, 105
Bilateral symmetry, 252, 253, 257
Bingham, Col. C. T., 239
Biological atoms, 158-69, 280
Biological molecules, 157-69, 280,

285, 291, 293, 294, 295, 344
Biological radicles, 158-69
Biophors, 153
"Bird Book, the," 207
"Birds of the Plains," 233, 303,

309, 359
Bison, 119, 126
Blackcock, 129, 131, 249, 278
Blackberry, 118
Blackbird, 201, 203, 207
Black-buck, 363
Blakiston, 181
Bloodsucker, 220
Blue-bellied waxbill, 104
Blyth, 115, 251
Boisier, 263
Bombyx arrindia, 125
B. cynthia, 124
Bonhote, 126, 288, 289, 290, 291,

292, 293, 337
Bontebock, 196

Boselaphus tragocamehts, 357, 363
Bos frontatts, 126
Boulenger, 88
Bower-bird, 306
Brain-fever bird, 235, 236, 248
Bramble, 261
BranchipuS) 156
Brannam, 92
Brent, Mr, 307



British Museum, 129, 130, 187

BubovirginiamiS) 221

Bubulcus coromandus, 254

Budgerigars, 101

Buffalo, 120, 199

Buffon, 2

Buff Orpingtons, 65

Buff-tip moth, 215

Bufo melanostictus, 219

Bulbul, 123, 220, 221, 244, 245,
255, 256, 279

Bull, 119

Bungarus ccerulcus, 217, 247

Bunting, reed, 98, 190, 289

Buphus corotnandus, 3i7> 318

Burbank, 118

Burnet moth, 102

Bush-buck, 196

Butcher-bird, 241, 253

Buttercups, 70, 267, 274

Butterfly, 45, 47, 102, 103, 196, 197,
203, 204, 209, 212, 216. 238,
239, 240, 250, 264, 280, 306, 381

Buzzard, 262

CACOMISTLE, 242

Cairina moschata, 127, 245

Californian currant, 119

Catenas nicobarica, 65

Calotes versicolor, 22O

Camel, 120, 357

Campophaga, 248

Canary, 100, 101, 102, 117, 120,

127, 280, 338, 362
Canis jubatus, 181
Capercailzie, 129, 131
Capuchin monkey, 216
Carbon, 153
Carduelis caniceps, 255
C. carduelis, 255
Carnation, 85, 86
Carnivores, 67
Carp, 102
Carrion crow, 123
Carrot, 71, 269, 270
Casarca cana, 129
C. tadornoides, 129
" Cassell's Book of the Horse," 69
Castle, 149

Castration, effects of, 335, 344
Cat, 61, 98, 99, loo, 206, 282, 283,

339, 350, 356, 361
Cat-rabbit, 125



390



Index



Cataloe, 119
Cataract, 340
Caterpillars, 155, 175, 205, 21 1, 21$,

221, 350

Cattle, 94, 95, 115

Centropus sinensis, 22O, 244

Ccphalophus dorite, 243

Cephalopyrus flammiccps, 244

Cervulus muntjac, 101

C. reevcsii, 114

C. vaginalis, 114

Cervus paludosus, 180

C. sika, 120

Ceryle rztdis, 202

Chaffinch, 289

Chamba monaul, 104

" Champion Ladybird," 91, 92, 93

Change of function, theory of, 36,

37

Chen nivalis, 282
C. rossi, 282

Chenatopex cegyptiaca, 316
Chenonetta jubata, 316
Chinese goose, 99, 114, 121, 130
Chinese pheasant, 123
Chloephaga dispar, 105
C. magellanica, 105, 334
C. rubidiceps, 105, 334
Chromosomes, 145-7
Chryscena victor, 333
Chrysolophus anther stice^ 121
C, obscurus, 97
C.pictus, ,97, 121,337
Chrysomitris colombiana, 244
Chrysalis <zstiva, 103
Ciconia alba, 282
C. boyciana, 282
Cinnabar moth, 227
Cissopis leveriana, 281
Civil Service Commissioners, 385,

387

Cleistogamous flowers, 260
Climate as check on multiplication,

349, 350

Clouded-yellow butterfly, 103
Clover, 69, 274
Clytus arietis, 178, 229
Cobra, 224, 225, 226, 358, 359
Colias edusa, 103
Colour-blindness, 340
Colouration of Flowers, Law of

Progressive, 66
of Organisms, 170-296



Columbidse, 331, 333

Concealing colouration, 184-7

Congenital characters, 1 8, 19

Conn, 47

"Contemporary Review," 26

Cope, 15, 67

Copsychus saularis, 281

Coracias affinis, 123, 255

C. indica, 123, 220, 255

Cordon-bleu, 104

Cormorant, 190, 191, 277, 381, 382

Corn, Indian, 81

Correlation, 39, 40, 117, 162, 167,

223, 339, 34, 344, 356-65
Corvus corone, 123, 255
C. comix, 123, 255
C. splendens, 353
"Country-Side, The," 261, 265,

266, 273, 304, 311, 313
Courser, 362
Court-bee, 72
Cow, 119, 120, 126
Crab, 155

Crane, 105, 247, 248, 279, 282, 292
Crateropus bicolor^ 242
C, canorus, 179
Crax globicera, 104, 304
C. grayi, 104
C. hecki, 104, 304
Crested newt, 124
Cretaceous reptiles, 67
Crinoids, 67
Crocodile, 187

Cross-fertilisation, 69, 258-60
Crotalus, 223
Crow, 47, 123, 206, 220, 247, 255,

281, 353, 355, 359, 361
" Crow-pheasant," 220
Cryptic colouring, 173
Cuckoo, 220, 233, 235, 236, 243,

244, 247, 248, 289

shrike, 248

Cuculus eanoriiS) 289

Cuenot, 149

Cunningham, Col., 225, 226, 358

J. T., 15, 19, 20, 324, 325, 329,

331, 332, 333, 336
Cupples, Mr, 308
Curassow, 104, 304
Currant, 119
Cut-throat finch, 122
Cypselus affinis, 243
Cytisus adami) 119



391



The Making of Species



DAFILA ACUTA, 122

Dahlia, 86

Daisy, 266, 274

Daltonism, 340

Damaliscus tunatus, 363

Damp as a check to multiplication
of species, 350, 351

Danaidce, 175, 179, 215, 216, 226,
228

Danais chrysippus> 179, 250

Danger signal, 183, 214, 253, 254

Darter, 277

Darwin, I-I2, 14, 25-27, 31, 35,42,
S 2 , 54-7, 59, 60-3, 68, 83, 96,
112, 114-7, "9, 123, 127, 130,
151, 171, 175, 182, 184,233,259,
299, 301-8, 316, 319-21, 325,
326, 347

"Darwin and after Darwin," 370-

5, 377, 38i
Darwinian theory, 3, 5-8, n, 13,

27,28,35,42,45,52,75, in, 171
Darwinism, I, 7, 8, n, 14, 26
"Darwinism," 40, 53, 112, 117,

178, 207, 213, 228, 322, 323
"Darwinism To-day," 16, 45, 67
Dasyurus, 283
De Candolle, 86
Decorative plumage, 40
Deer, 101, 120, 180, 298
Deerhound, 304, 308
Deer-ponies, 125
Degeneration, 168
Dejerine, 340
Delage, 33, 147
Delbceuf, Law of, 373
Delias eucharis, 2 1 6, 220, 221
Demicgrttta, 100
Demoiselle crane, 277
" Descent of Man," 234, 299, 301,

302, 304, 305, 319, 320, 326
Determination of sex, 165
"Development and Heredity," 17
De Vries, 26, 66, 69-72, 75-8, 82-9,

95, 105, 118, 151
Dewar, D., 43, 44, 47, 48, 195, 204,

206, 208, 210, 225, 233, 236, 303,

308, 309, 354, 360, 378
Dewar, G. A. B., 196, 197
Dicrurus ater, 179, 233
Didtlphys nurina, 243
Dimorphism, sexual, 51, 200, 201
Dipsacus, 58



Disease as a check to multiplication

of species, 351

Dt 'ssenntrus paradiseus, 179, 220
Divergence of character, 367
D g 59, 68, 99, 100, 125, 225, 226,

282, 283, 304, 308, 352, 357, 364,

365

Dog-rose, 261
Dolphin, 99

Dominant characters, 142
Donald, Mr D., 256
Dragon-fly, 216, 264
Driesh, 136
Drongo cuckoo, 233
Drongo-shrikes, 179, 220
Drummond, 382
Duck, 51, 60, 68, 97, 99, 100, 122,

126-8, 190, 247, 249, 282, 292,

3.14, 315, 334, 337, 338, 365
Duiker-buck, 243
Dyer, Sir William Thistleton, 26

EAGLE, 65, 190, 350

Eagle-owl, 221

East, M. E., 79

Echis carinatct) 224

" Eclipse," 69

" Edinburgh Review, The," 38

Eel, 102

Eggs, colours of birds', 206-9

Egret, 100, 206, 254, 365

Eider-duck, 249

Eimer, 15, 16, 33

Eisig, 222

Elanoidesfurcatus, 282

Elaps, 197, 198

Elder, 49

Elementary species, 77, 78, 87, 88, 89

Elk, Irish, 67

Emberiza citrinella, 289

E. pyrrhuloides, 98

E. schceniclus, 98

Entom oph ila p icata, 281

Entomophilous flowers, 261

Epenthesisfolleata, 103

Epilobias, 260

Equus, 41

Erebia manto, 381

Erythrura prasina> 1 02

"Essays on Evolution," n, 173,
177, 181, 184, 213, 223, 226,
227, 229, 230, 231, 234, 237,
238, 239



39 2



Index



Estrelda cyanogastra, 104
E. phcenicotis, 104
Ether, 152, 153
Eucheliajacobacce, 227
Eurasian, 140
European, 140
Euxenura maguari, 282
Evening primrose, 84, 85, 88
"Evolution of Sex, The," 306
Existence, struggle for, 31, 32
Eye-colour in human beings, 310
Eyesight of birds, 21 1, 237-41

insects, 264

Eyton, 15



"FAERY YEAR, THE," 196

Falcon, 204, 246, 250

Falco peregrinator, 25 1

F. severus, 251

False mimicry, 243

Faults in poultry, 64

Ferrets, 100, 119

Finch, 117, 120

Bicheno's, 105

chestnut-breasted, 98

cut-throat, 122

Gouldian, 98

Nonpareil, 102

red-headed, 142

ringed, 104

saffron, 244

yellow-rumped, 98

Finn, 99, 102, 115, 131, 179,216,
219, 220, 235, 241, 255, 304,
309, 310, 313, 315, 316, 358

Fittest, survival of the, 32

Flowers, 65, 66

Flowers, colours of, 258-75

Fly-catchers, 44, 45, 47, 285, 338

Flying squirrel, 243

"Fortnightly Review, The," 37, 38

Foul-brood, 353

Fowl, 56, 58, 61, 64, 65, 99, 101,
125, 127, 128, 282, 301, 302,
307, 3H, 330, 336, 338, 339,
361, 362, 364, 365

Fowl-ducks, 125

Foxes, 101, 131, 190, 191

Fox-terrier, 19

Franqueiro cattle, 95

Francolinus pondtcerianus, 337

Friar-bird, 249



Fringella coelebs^ 209
Fritillary butterfly, 103
Frog, 325

Fruits, colours of, 258, 275
Fiiligula marila, 290
Fulmar petrel, 190
Function, change of, 36, 37
Fungi, 263

GADOW, Dr, 197, 245

Gadwall, 126, 315

Galton, 81, 82, 374

"Game Birds and Wild Fowl of

India," 131

Gametes, segregation of, 143-5
Gannet, 282
Gayal, 126
Gauchos, 359
Gecko, 210
Geddes, 306, 326
Gemmules, 151
"Genesis of Species," 7, 61
Geographical isolation, 375
Geological record, imperfection of,

40-2, 94
Geranium, 260

Germ-plasm, continuity of the, 25
Germinal variations, 106-10
Geum urbanum, 263
Gibbon ape, 101
Giraffe, 17, 18, 192, 196
Globicera, 104
Glutton, 190
Goat, 283


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Online LibraryDouglas DewarThe making of species → online text (page 23 of 24)