_Chærocampa._ _C. elpenor_ and _C. porcellus_, relationship of, 171; markings of larvæ of the genus, 177; _C. elpenor_, 1st and 2nd larval stages, 178; 3rd and 4th stages, 180; 5th stage, 181; 6th stage, 183; _C. porcellus_, 1st larval stage, 184; 2nd and 3rd stages, 185; 4th stage, 186; _C. elpenor_ and _porcellus_, larval markings compared with other species of _Chærocampa_, 188; _C. elpenor_, experiments with larva, 331, 332; _C. Japonica_ and _C. Lewisii_, larvæ, 194; _C. cretica_, larva, 524; _C. lycetus_, larva, 527; _C. capensis_, larva, 529; eaten by birds, &c., 530. Characters, new, backward transference of, 279. Chauvin, Fräulein von, experiments with Axolotl, 558; experiments with _Salamandra atra_, 615. Chavannes, figure of larva referred to, 255. Clarke, development of _Amblystoma punctatum_, 623. Classification, objects of, 168. Claus, on the origination of heterogenesis, 89. Clemens, larva of _A. ello_, 268. Climatic variation, 45; in _P. Napi_, 47; in _E. Belia_, 47; nature of causes producing, 52, 105; by sex, 61, 62; climatic varieties very distinct from local, 45; climatic influences operate slowly, 58; climatic changes gradual, 652, 660. Cole, B. G., seasonal dimorphism of _E. punctaria_, 4. Coleoptera, grub-like larvæ of, 495. _Colias edusa_, dimorphism of female, 250. Colour, biological value of, 289. Conditions of life, compulsory changes in, 651. Congruence in Lepidopterous families, 435; in Lepidopterous genera, 444. _Coniferæ_, food-plants of _Anceryx_, 268. Convergence of characters in _Ophiuroidea_, 396; in Dipterous larvæ, 494. Cope, Prof., habits of _Siredon Mexicanus_, 566; on distribution of _Amblystoma_, 569. Correlation of growth, 278, 363, 388, 415; action of, 415, 516; Von Hartmann’s views of, 670; nature of, 673. _Cryptobranchus_, characters of, 579. Cyclical propagation, 82, 699; and reversion, 613. D. Daphniacea, differences between allied species and genera, 516. Darwin, C., influence of external conditions of life, 59; inheritance at corresponding periods, 63, 275, 431; markings of butterflies, 101; definition of eye-spots, 326; adaptation in larvæ, 392; correlation of growth, 516; degeneration, 583; adaptation, 589; causes of sterility, 596; limited variability, 656; factors of variability, 676; abrupt variations, 701. Degeneration, 583; phyletic, 611.