Charles Darwin

summary

Alphabetical glossary of biological, zoological, botanical and geological terms with short definitions (e.g. Carapace, Cephalopods, Mammalia, Pleistocene).
Extensive index cross-referencing topics, authorities and page locations.
Acknowledgement of Project Gutenberg as the public-domain source.

summary

Numbered footnotes compiling citations, specimen records, and field observations on zoology, botany, geology, and climate from voyage research.
Frequent references to other authorities (Lyell, Humboldt, etc.), specific natural-history remarks (species, fossils, island biogeography) and methodological notes.
Concludes with acknowledgments to contributors and Project Gutenberg.