Palm trees, fertilization of, 61
Parasites, 63, 64

Parker, G. Н., 240, 315

Parthenogenesis, 198
Passenger pigeon, 86

Passes, importance of, 30
Pasteur Institute, 143, 145
Pearson, Karl, 211-212, 228, 236-
238; study of school children
in Great Britain, 257, 258
Peas, Mendel's experiment on,
200, 202

Petroleum, 13, 106

Physical world, influences of, on
man, 28

Physiological effects of tempera-
ture, 35

Plants, benefit of, to man, 53;
chemical elements in, 52;
dangers of careless discrimi-
nation between, 83; flowering,
118; imported, and native of
U. S., 113; leguminous, 13;
mechanical effects produced by,
51; origin of cultivated, 112;
perfected by crossing, 114;
protection of, 53

Ploss, H., 323, 327-328
Pneumonia, 141
Polydactylism, 236
Population, contrasted in vari-
ous states, 29; density of
world's, 28; influences of so-
ciety on, 33
Primates, 184

Primitive man, discoveries of,
186; variation from present
man, 188

Radical, the, 370
Radium, discovery of, 3, 141;

properties, 4

Rainfall, 18; influence on plant
growth, 19

Rays, alpha, 4; beta, 4; gamma, 5
Red clover, 60

Reformatory, inmates of the,

252

Regression, law of, 228
Reibmayr, A., 271, 347, 384
Reich, E., 383-384

Reid, G. A., 344-345
Religious fanaticism, influence
on society, 346
Reproduction: cell division, 194;
cell specialization, 192; germ
and body cells, contrast, 195;
growth, 192; rate of, 70; sex
differences, 196; stationary
total, 71

Research, methods of, 148, 191
Rhythm of nature, 47

Ripley, W. Z., 280, 283, 285,
290-291

Rockefeller Institute for Medical
Research, N. Y. C., 143

Roosevelt, T., 70

Royal Observatory of Greenwich,

1

Rubber, 110; plants and prod-
ucts, 112

phenomena, 38

Segregation, of "unfit," 267
Selection, artificial, natural, sex-
ual, 178; evidences for, 180
Semper, K., 28
Semple, E. T., 31, 32, 102, 103
Sex, determination of, 207
Sex, human, differences: advent
physical maturity, 323; ath-
letic records, 318; beginnings
of, 312; blood composition,
321; bodily proportions, 318-
319, 323; brain weights, 320-
321; differences do not indi-
cate superiority, 329; growth
of boys and girls, 316-317;
influence on daily life, 326;
influence of menstruation, 323-
326; males and females in U.
S., 314; psychic phenomena,
326; resistance to shock, 322;
secondary sexual characters,
315; sex ratios, 313; stature,
weight, 317-318; two theories
as to rôle of women, 329-330;
variability, 327-328
Sex-linked characters, 209
Sheep, crossing of Dorset horned
with hornless Suffolks, 210
Shelford, V. E., 26, 27, 28, 46,
57, 59

Silk worm, 125
Sixties of Ohio, 266

on, 339; permanency of, 387;
progress of, through surgical
skill and medical knowledge,
343; religion and, 339; Spen-
cer's idea of, 378

Society tests: choice of right
virtues and right crimes, 387;
elimination of unfit, 389;
power of readjusting institu-
tions and programs to meet
changing conditions of life,
390; protection afforded, 388;
training of children, 389
Sociology, danger of applying
biological laws, 381; a science,

377

Soils, characteristics and classi-
fication, 11; meaning to
farmer, 13

Sparrow, European house, 90
Spectroscope, 14
Spencer, H., 378
Spermatozoon, 192
Spontaneous generation, 151
Standards, conflict of different,

363

Stars, classification, 1; helium-
gas, 1; metallic, 2; proto-
hydrogen, 1; protometallic, 2
Statistical methods, 228
Steam engine, 108
Steel, 107

Sterilization, 267

Stockard, C. R., 221-223
Struggle for existence, 65
Subnormal man, 241

Suicide, increase of, in civilized

lands, 348

Sun, 13

Superman, nature of, 262

Supernormal man, 241
Surface, M. A., 80

Swine, 122

Switzerland, population

per