Dews, cause of heavy tropical, 10 Diagram of mean temperature at Batavia and London, 5 of rainfall at Batavia and London, 15 _Dianthus alpinus_, _D. glacialis_, 232 Distribution of humming-birds, 138 Dragons or flying-lizards, 113 Drugs from equatorial forest-trees, 36 Duke-of-York Island, pale-coloured insects of, 259 Islands, remarkable white plumaged birds of, 263 Dyes from equatorial forest-trees, 36 Dynastidæ, 95 probable use of horns of, 202 E. Earl, Mr. George Windsor, on division of Malay Archipelago, 307 Earth-sculpture or surface-geology, 250 Earthworks, North American, 292 Easter Island, sculptures on, 291 Eciton, genus of foraging ants, 87 Elateridæ, luminous species perhaps mimetic, 205 Emperor-moth, protective coloration of, 174 Environment, relation of living things to, 254 _Epicalia_, sexes of, differently coloured, 178 _Epilobium angustifolium_, _E. parviflorum_, 233 Epimachinæ, 150 Equator, cause of uniform high temperature near, 6 short twilight at, 21 Equatorial climate, general features of, 17 uniformity of in all parts of the world, 18 local diversities of, 19 Equatorial forests, general features of, 29 Equatorial forest-belt, cause of, 27 Equatorial heavens, aspect of, 23 Equatorial zone, temperature of, 3 Ethiopian Region, 317 _Eugenes fulgens_, 134 Eunica and Siderone, resemblance of species of, 257 Euplœa, pale species of, in Moluccas and New Guinea, 258 Euro-Asiatic continent, Miocene fauna of, 323 Eustephanus, 141 _Eustephanus galeritus_, 143 _Euterpe oleracea_, 43 Evaporation and condensation, equalising effects of, 16 F. Female birds, greater brilliancy of some, 211 Female insects, greater brilliancy of some, 203 Ferns, 46 Ferns, preponderance of in Tahiti and Juan Fernandez, 269, 270 Fiji Islands, pale butterflies of, 259 Fire-ants, 83 Fishes, causes of general coloration of, 171 Flowering trunks, probable cause of, 34 Flowers, comparative scarcity of in equatorial forests, 60 Flowers and insects, 64 Flowers of temperate zones brilliantly coloured, 165 comparatively scarce in tropical forests, 167 Flowers, attractive colours of, 228 fertilized by insects, 228 attractive odours of, 230 when sweet-scented not conspicuously coloured, 230 attractive grouping of, 231 alpine, why so beautiful, 232 why allied species differ in beauty, 233 when wind-fertilized not coloured, 233 relation of colours of, to distribution, 235 and fruits, recent views as to action of light on, 236 Flowers of Auckland and Campbell’s Isles, bright-coloured, 238 Flying-lizards, 113 Foliage, two chief types of, in tropical forests, 33 colours of, 221 Foot of savages does not approach that of apes, 289 (note) Forest-belt, cause of equatorial, 27 Forest-belts, temperate, 29