_Ceroxylus laceratus_, imitates a moss-covered stick, 64. CERTHIOLA, sexual colouring and nidification of, 244. _Cethosia aeole_, 172; _biblis_, 172. CETONIADAE, how protected, 73; similar colours of two sexes, 114. CEYCOPSIS, 196. _Charis melipona_, 96. CHEMATOBIA, wintry colours of this genus, 62. _Chlamys pilula_, resembles dung of caterpillars, 58. CHRYSIDIDAE, how protected, 72. CHRYSOMELIDAE, similar colouring of two sexes, 114. CICINDELA, adaptive colour of various species of, 57. _Cilix compressa_, resembles bird's dung, 63. CLADOBATES, mimicking squirrels, 107. CLASSIFICATION, form of true, 6; circular, inadmissible, 8; quinarian and circular, of Swainson, 46; argument from, against Mr. Darwin, 295. CLIMACTERIS, sexual colouring and nidification of, 243. COCCINELLIDAE, how protected, 72; similar colouring of sexes, 114. COEXISTING varieties, 159. _Collyrodes lacordairei_, 95. COLOUR, in animals, popular theories of, 47; frequent variations of, in domesticated animals, 48; influenced by need of concealment, 49; in deserts, 49, 50; in Arctic regions, 50, 51; nocturnal, 51; tropical, 52; special modifications of, 52; different distribution of, in butterflies and moths, 58; of autumnal and winter moths, 62; white, generally dangerous and therefore eliminated, 66; why it exists so abundantly although often injurious, 69; influenced by need of protection, 113; of female birds, 114; in relation to nidification of birds, 116; gaudy colours of many caterpillars, 117; in nature, general causes of, 126; local variations of, 173; sexual differences of, in birds, 239; in female birds, how connected with their nidification, 240, 246; more variable than structure or habits, and therefore more easily modified, 249; of flowers, as explained by Mr. Darwin, 262; often correlated with disease, 316. COMPSOGNATHUS, 300. _Condylodera tricondyloides_, 97. CONSCIOUSNESS, origin of, 360; Professor Tyndall on, 361; not a product of complex organization, 365. CORRELATION of growth, 310. _Corynomalus sp._, 92. COTINGIDAE, sexual colouring and nidification of, 244. CRATOSOMUS, a hard weevil, 94. CRICKETS mimicking sand wasps, 98. CRYPTODONTIA, 299. _Cucullia verbasci_, 120. CURCULIONIDAE, often protected by hard covering, 71; similar colours of two sexes, 114. _Cuviera squamata_, 258. _Cyclopeplus batesii_, 92. CYNOPITHECUS, 196. _Cynthia arsinoe_, 172. DANAIDAE, the subjects of mimicry, 85, 86. _Danais erippus_, 88; _chysippus_, 112; _sobrina_, 179; _aglaia_, 179; _tytia_, 180.