A

Acquired characters not inherited, 52.

Adaptation and purpose, 89.

Adaptation for the individual, 87.

Adaptation for the species, 125.

Advanced teaching, 291.

Agassiz and evolution, 19.

Age of the earth, 156.

Allantois of chick, 206.

American Museum of Natural History, 221.

Anaxagoras and evolution, 9.

Anaximander and evolution, 8.

Ancestry of man, 186.

Andes rising out of Pacific, 32.

Aquinas, Thomas, and evolution, 12.

ArchÆopteryx, 181.

Aristotle and evolution, 9.

Armadillo and glyptodon, 29.

Artificial flavors, 161.

Artificial proteids, 161.

Artificial sugars, 161.

Ascent of man, 189.

Asexual reproduction, 194.

Augustine, Saint, and evolution, 11.

Australian mammals, 186.

B

Bank swallow's nest, 146.

Barnacles studies by Darwin, 34.

Beagle and Darwin's voyage, 25.

Beauty of human female, 127.

Biologists accept evolution, 278.

Bird colors, 131.

Bird from reptile, 122.

Bird nests, 145.

Birds of a region definite, 61.

Bird song, 135.

Blowing viper, 107.

Blue birds and frost, 61.

Bradbury, Dean, 43.

Buffon and evolution, 15.

Bumble bees, 125.

Butterfly colors, 129.

Butterfly's mouth, 95.

C

Carboniferous age, 174.

Carnivorous teeth, 124.

Caterpillars on leaves, 110.

Cave man, 188.

Cells live in water, 166.

Cenozoic age, 185.

Cicada killer, 143.

Circular nest of bird, 147.

City life in man, 256.

Clothing of birds, 101.

Coal plants, 174.

Cold-blooded animals, 99.

Color, concealing, Thayer, 115.

Concealing appearance, 105.Cope and Lamarckianism, 244.

Cope on taste of toad, 118.

Coral reef formation, 32.

Country life in man, 256.

Cretaceous period, 180.

Cricket song, 134.

Crinoids, 171.

Crossing and variation, 53.

Cuvier criticises Lamarck, 19.

D

Darwin, Charles,
along La Plata, 28.
at Buenos Ayres, 28.
at Keeling Atoll, 31.
at Galapagos, 30.
father of evolution, 21.
in Brazil, 27.
in Patagonia, 29.
in Peru, 30.
on Beagle, 26.
persuaded world of evolution, 21.
studies Lyell's Geology, 26.
studies Malthus, 35.

Darwin, Erasmus, and evolution, 16.

Darwin's ancestry, 22.
birth, 23.
burial in Abbey, 43.
death, 43.
education, 23.
narrative of voyage, 33.
patient mind, 45.
purity of mind, 29.
return to England, 33.
short sketches, 39.
study of barnacles, 34.
work double, 233.

Deer horns, 138.

Descartes and evolution, 12.

Descent of man, 189.

Determinants in nucleus, 238.

Development of chick, 204.

Development of pond-snails, 46.

Devonian age, 173.

Devonian fish, 173.

DeVries and mutation, 246.

Duckmole, 208.

E

Early marriage, 272.

Earth's age, 155.

Ecstatic flight, 136.

Egg-laying mammals, 208.

Eimer and orthogenesis, 243.

Elements of Geology, Lyell, 26.

Emanuel Kant and evolution, 13.

Embryo of chick, 203.

Emerson and nature, 48.

Empedocles and evolution, 8.

English sparrow (see Sparrow, English).

Environment in man, 258.

Eugenic program, 269.

Evening primrose and mutation, 246.

Evolution since Darwin, 233.

F

Feeble-mindedness, 264.

Feet of mammals, 122.

First living things, 165.

Fish eggs, 145.

Fish may freeze, 104.

Fitz-Roy, Capt., and Beagle, 25.

Freedom of teaching, 291.Fright paralysis, 108.

Frog's long tadpole stage, 112.

Frost and bluebirds, 61.

Fur of seal, 100.

Future evolution of man, 249.

G

Galapagos Islands and evolution, 30.

Geological periods, 158.

Glyptodon and armadillo, 29.

Goethe and evolution, 20.

Graphite from plants, 168.

Grasshopper's mouth, 93.

Grasshopper song, 133.

Groundhog and winter, 103.

Growth of North America, 167.

H

Haeckel advocates evolution, 42.

Health certificates, 263.

Henslow and Darwin's education, 24.

Henslow suggests Darwin for Beagle, 24.

Heredity and natural selection, 45.

Heredity in man, 258.

Homes, few animals have, 98.

Homes, warm-blooded animals, 101.

Horn of rhinoceros, 123.

Horns of deer, 138.

Horse and early man, 232.
earliest, 223.
neck, 229.
story of, 220.
three-toed, 227.

Horseshoe crab, 171.

How mammals developed, 192.

Huxley at Oxford meeting, 42.

I

Ichneumon fly, 142.

Image of God, 288.

Improving the environment, 259.

Improving the stock, 261.

Inheritance of acquired characters, 238.

Insect's biting mouth, 93.

Interpretation of Genesis, 284.

Isolation, Jordan, 242.

Isolation, Romanes, 242.

Isolation, Wagner, 241.

J

Java skull, 187.

Jehovah confounding the nations, 289.

Jordan and isolation, 242.

Judgment, Michael Angelo, 289.

Jukes family, 265.

June-bug, 107.

K

Kallikak family, 265.

Kant and evolution, 13.

Katydid's color, 111.

Katydid's song, 133.

Keeling Atoll and Darwin, 31.

King Crab, 171.

L

Lamarck and evolution, 17.

Lampshells, 172.La Place's theory, 151.

Leibnitz, and evolution, 13.

Life from other planets, 162.

Life in the past, 149.

Life, its nature, 247.

LinnÆan Society and evolution, 40.

LinnÆus and fixed species, 15.

Locust's song, 135.

Lucretius and evolution, 10.

Lung-fish, 176.

Lyell's Geology, 26.

M

Male birds brighter, 131.

Male insects sing, 134.

Malthus and population, 35.

Mamma, significance of, 211.

Mammals, egg-laying, 208.
how developed, 192.

Man and God's image, 288.
early, and horse, 232.
growing better, 255.

Man's ancestry, 250.
future evolution, 249.

Mating and song, 133.

Mating antics, 136.

Meaning of Genesis, 284.

Megatherium and sloth, 29.

Mesozoic age, 178.

Michael Angelo, Judgment, 289.

Migration of birds, 103.

Missing link, 187.

Mizpah, 283.

Modern teachers of biology, 291.

Mongolian idiot, 265.

Mosquito's bite, 97.

Mosquito's mouth, 96.

Mother-love, 217.

Multiplication and evolution, 54.

Mutation and DeVries, 246.

N

Nature of life, 247.

Nature of milk, 214.

Natural selection explained, 45.
in brief, 36.

Nebular hypothesis, 152.

Neck of horse, 229.

Neo-Darwinians, 237.

Nests for warm eggs, 101.

Number and position of breasts, 215.

O

Odor as protection, 117.

Opossum playing dead, 107.

Origin of birds, 181.
feathers, 102.
flight, 122.
hair, 102.
life, 159.
lungs, 177.
milk glands, 212.
placenta, 210.
variations, 50.

"Origin of Species" published, 41.

Orthogenesis and Eimer, 243.

Oxford meeting of British Association, 41.

P

PalÆozoic era, 170.

Paley's Natural Theology, 87.

Pangenesis, 236.

Patagonia and its terraces, 29.

Phenacodus, 185.

Physical evolution of man, 254.

Pithecanthropus, 188.

Planetesimal theory, 155.

Playing dead, 107.

Playing 'possum, 107.

Polygamy in animals, 137.

Pond-snail, development of, 46.

Potato worm, 142.

Protective coloration, 109.

Protoplasm, 164.

Pterodactyl, 180.

Puff adder, 107.

Purpose and adaptation, 89.

Purpose in nature, 88.

Q

Quiet and escape, 105.

R

Raining toads, 113.

Religion and evolution, 74.

Reptiles of Mesozoic, 179.

Reproduction, asexual and sexual, 194.
in fishes, 196.
in frogs, 199.
in reptiles, 202.

Rhinoceros horn, 123.

Romanes and isolation, 242.

Rooster finer than hen, 132.

S

Saint Augustine and evolution, 11.

Salamanders, 176.

Sargent's picture, 289.

Science and the book, 274.

Science and theology, 280.

Science, definition, 280.

Seals and polygamy, 139.

Sealskin and fur, 100.

Sedgwick and Darwin, 24.

Selection and evolution, 56.

Sexual selection, 126, 128.

Skunk's odor, 117.

Sloth and megatherium, 29.

Song and mating, 133.Sparrow, English, adapted to town, 66.
and hawks, 69.
and winter, 73.
eat varied food, 71.
eye-minded, 78.
feed young on insects, 72.
good qualities, 85.
has reached limit, 85.
in Philadelphia, 63.
introduction, 62.
lives near houses, 70.
nests early, 81.
nests often, 82.
once migratory, 80.
quarrels without animosity, 75.
sociable, 74.
spread of, 65.
stays over winter, 79.
successful, 83.
transported in cars, 67.
unafraid of man, 69.
wintering, 73.Sparrow, House, 62.

Sphex wasp, 143.

Spider cocoons, 139.

Spider, young, 140.

Spontaneous generation, 159.

Stone lilies, 171.

Story of the horse, 220.

Struggle against enemies, 104.
for food, 91.
for shelter, 92.
for the individual, 90.
for the species, 91, 125.

Sunfish and young, 196.

T

Taste of toad, 118.

Teeth of mammals, 98.

Temperature of mammals, 99.

Tertiary era, 185.

Thayer, concealing color, 115.

Theology and science, 280.

Theology, definition, 280.

Thomas Aquinas and evolution, 12.

Three-toed horse, 227.

Toad, bad taste, 118.
color, 112.
enemies, 113.
short tadpole stage, 112.

Tomato worm, 142.

Turtles and young, 202.

Tusks of elephant, 124.

Tussock worm, 64.

Two methods of reproduction, 194.

Types of insect mouth, 93.

U

Understanding the Bible, 281.

Underwing moth, 130.

V

Variation and natural selection, 49.
by crossing, 53.

Virchow and man's ancestry, 187.

Vireo's color, 115.

W

Wagner and isolation, 241.

Wallace and evolution, 39.

Warm-blooded animals, 99.

Weissman and evolution, 235.

Wilberforce, Bishop, and evolution, 41.

Wintering of ground hog, 103.

Wintering of mammals, 103.

Wintering of squirrels, 103.

Woodchuck, 103.

Woodpecker's nest, 146.

Y

Young growing finer, 272.