Rocks, crystalline or plutonic: sedimentary, 85; eruptive, 88; new, 59; of Grand Cañon, 90; testimony of, establishes evolution, 100.
Salamanders, 45, 46.
Salts, of sodium, chlorine, magnesium, potassium, 24.
Samoan Islands, 103.
Sandstone, 90.
Science, what is it? 5, 6; physiological, 14.
Sea anemones, 68.
Sea elephant, 38.
Seals, 38, 39, 40, 209.
Selection,
natural, doctrine of, 116, 117, 118;
struggle for existence, 124, 125;
simply trial and error, 131, 136,
artificial, 136, 137, 138;
laws of, in mental phenomena, 203.