Form-relationship and blood-relationship, not always coincident, 395. Frantzius, Von, on climate of Mexico, 619. Frogs, 615, 616, 618; inedible species, 294. Function, change of, 365. G. Gegenbaur, Prof., the skull of Axolotl, 576. Gehrig, breeding of Axolotl, 565. Gené, habits of _Euproctus Rusconii_, 617. Genera, Lepidopterous, show greatest congruence, 459. Generation, heterogeneous, 679, 698, 702. Gentry, T. G., phytophagic variability of caterpillars, 306. Gerstäcker, division of the Diptera, 498. _Geotriton fuscus_, habits, 617. Glacial epoch; butterflies monogoneutic during, 19, 72; in N. America, 622. Gooch, W. D., description of larvæ referred to, 436; crepuscular butterflies, 476; sexual dimorphism of caterpillars, 535. Gooseberry, not increased in size, 654. Goss, H., larva of _C. porcellus_, 188. Gosse, P. H., embryonic larva of _P. Homerus_, 167. _Grapta interrogationis_, experiments with, 149. Green colour of caterpillars, 293, 310. Growth, law of, 655. Gynandromorphism in butterflies, 249. _Gynanisa Isis_, young larva, 166. H. Haeckel, Prof., on metagenesis, 80, 83; on ontogeny, 270; on adaptation, 281, 589; on the biogenetic law, 611; on reproduction and growth, 664; the plastidule theory, 667. Hare, white variation of, 660. Hartmann, E. von; his views examined, 645; on variability, 646, 652, 655, 664; on heredity, 657; his “Philosophy of the Unconscious,” 670; on correlation, 670, 673; on the nature of species, 671; on design in nature, 696; on the sensibility of atoms, 714. Helmholtz, Prof., on natural laws, 668; on the senses, 711. _Hemaris hylas_, larva, 255. Heredity, alternating and continuous, 24; cyclical, 66; homochronic, 63, 431; not mechanical, 657; nature of, 667. Herrich-Schäffer, wing neuration of butterflies, 449. Hertwig, on teeth of Amphibia, 376. Heterogenesis, definition of, 82, 96; parallelism between and metamorphosis, 86; origination of, 89. Heyden, Von, reproduction of _Aphis_, 97. Hilgendorf, on fossil shells, 109. _Hipparchia semele_, colour variations, 8. Hoffmann, Ernst, on immigration of European butterflies, 77. Horsfield and Moore, figures of caterpillars referred to, 193, 195, 196, 243, 253, 261. Hübner, figures of caterpillars referred to, 193, 208, 211, 218, 231, 267. Humboldt, Baron, on the Lake of Mexico, 608, 621. Huxley, Prof., “Anatomy of Invertebrated Animals” referred to, 498. _Hydromedusæ_, alternation of generations in, 83; want of parallelism in different generations of, 395. Hydrozoa, asexual reproduction and polymorphosis, 83. Hymenoptera, incongruence among, 481; imaginal characters, 481; causes of incongruence, 486. I. Ichthyodea, characters of, 577, 579.