Darwin, experiment on Helix pomatia, [78]

on the permanence of oceans, [100]

on cloudy sky of Antarctic regions, [146]

on glaciers of the Southern Andes, [147]

on geological time, [211]

on complex relations of organisms, [226]

on oceanic islands, [242]

on seeds carried by birds, [257]

experiments on seed-dispersal, [258]

on natural history of the Keeling Islands, [286]