The Doctrine of Descent and Darwinism

according adaptation already Ammonites Amphibians animal world Annelids apes appearance Ascidian birds bone brain causes Cetacea character characteristics comparative anatomy connection continent Darwin definite dentition derivation diverge doctrine of Descent Echinoderms embryonic Eocene exhibit existence external facts families fauna fish formation fossil Ganoids Gastrula gemmules genera genus geological Goethe grade gradually groups Haeckel heredity higher horse hypothesis idea individual infer intermediate forms islands lancelet language larva larvæ likewise linguistic Linnæus lower mammals Marsupials Medusa ment merely metamorphosis modifications morphological mutability natural selection naturalist observation Oolite organisms origin ovum peculiar pedigree perfect period phase phenomena placenta plants polypes possess present primordial produced progenitors races regard relations remains reproduction reptiles Rütimeyer says scarcely sexual Silurian skull species sponges strata structure systematic Tertiary tion transformation transition true Ungulata Ungulates varieties vegetal vertebral column Vertebrata vertebrate animals whole