Part 24

Fishes, lowest among common vertebrates, 46; trunk-fish, cow-fish, puff-fish, mouse-fish, flounder, 46; most primitive backboned animals, 92; 94; 157; embryos of, 171.

Fiske, 139.

Flies, may, 259.

Flounder, a variant of the fish theme, 66.

Fossilization, conditions of, 77-78.

Fossils, 73-105; remains of, 73; groups, 77; 78, 79; order of succession, 91; oldest rocks devoid of, 92; forms, 99.

Fowl, game cock, 138; pigeons, 138.

Frog, 45; eggs of, larva, development of, 58, 59, 60, 68.

Galapagos Islands, 102, 103, 104.

Galton, 142, 147; heredity of mental qualities, 232.

Gametes, 252.

Gastrula, 68.

Gemmules, 143.

Genera, 32.

Generation, spontaneous, 78.

Geographical distribution, 32.

Geological agencies, rain, rivers, glaciers, 88; construction, volcanoes, 88.

Geology, data of, 83, 84.

Germ, Bonnet's idea of, 70; cells, 144, 146; plasm, 145, 146.

Gibbon, 163.

Gills, 58, 62.

Gill-slits, bars, clefts, 61, 62, 64; in embryos of lizards, birds, mammals, 69; 171.

Giraffe, 133.

Glaciers, alterations made by, 87.

Goats, 157.

Gorilla, 163, 165, 195.

Grand Canon of the Colorado, 85, 90.

Gravitation, 155.