Sedgwick, A., address at the British Association (1899).

Sedimentary strata, conversion into schists.

Sedimentation, connection with elevation and subsidence. -near coast-lines.

Seedlings, sensitiveness to light.

Seeds, collected by girls in Prof. Henslow's parish. -dispersal of. -effect of immersion on. -of furze. -Asa Gray on Darwin's salt-water experiments. -germination after 21 1/2 hours in owl's stomach. -moss-roses raised from. -peaches from. -variation in. -bright colours of fruits and. -difficulty of finding in samples of earth. -dormant state of. -germination from pond mud. -Hildebrand on dispersal of. -mucus emitted by. -stored by ants. -supposed vivification of fossil. -vitality of.

Seeley, Prof.

Seemann, on commingling of temperate and tropical plants in mountains of Panama. -on the "Origin" in Germany. -mentioned.

Segregation of minerals in foliated rocks.

Selaginella, foot of, compared with organ in Welwitschia seedling.

Selection, a misleading term. -artificial. -as means of improving breeds. -importance of. -influence of speedy. -utilised by pigeon-fanciers. -Sexual (see Sexual Selection). -sterility and. -unconscious. -and variation. -voluntary. -and inheritance.

Self-fertilisation, abundance of seeds from. -Darwin's experiments on cross- and. -evil results of. -comparison between seeds from cross- and. -in Goodeniaceae. -in Orchids.

Self-interest, Preston on.

Self-sterility, in Eschscholtzia. -in plants. -connection with unnatural conditions.

Selliera, Hamilton on fertilisation-mechanism.

Semper, Karl (1832-93): Professor of Zoology at Wurzburg. He is known for his book of travels in the Philippine and Pelew Islands, for his work in comparative embryology, and for the work mentioned in the above letter. See an obituary notice in "Nature," July 20th, 1893, page 271. -letter to.

Senecio. -S. vulgaris, profits by cross-fertilisation.

Sensitive plants, Darwin's work on.

Sensitiveness, diversified kinds in allied plants.

Separate creations, Darwin on.

Sequoia.

Seringe, on Aconitum flowers.

Sertularia.

Sethia, dimorphism of.

Settegast, H., letter to.

Severn, Darwin on floods of.

Seward, A.C., "Fossil Plants as Tests of Climate."

Sexes, colour, and difference in. -proportion at birth. -proportion in animals.

Sexual likeness, secondary.

Sexual organs, as collectors of generative elements. -appendages in insects complemental to.

Sexual reproduction, Galton on. -bearing of F. Muller's work on essence of.

Sexual Selection, Bates on. -Darwin on. -article in "Kosmos" on. -colour and. -man and. -in moths and butterflies. -subordinate to Natural Selection. -Wallace on colour and. -Wallace on difficulties of.

Sexuality, Bentham on. -in lower forms. -origin of.

Shanghai, tooth of Mastodon from.

Sharp, David, on Bombus. -on Volucella. -"Insects."

Sharpe, Daniel (1806-56): left school at the age of sixteen, and became a clerk in the service of a Portuguese merchant. At the age of twenty-four he went for a year to Portugal, and afterwards spent a considerable amount of time in that country. The results of his geological work, carried out in the intervals of business, were published in the Journal of the Geological Society of London ("Quart. Journ. Geol. Soc." Volume V., page 142; Volume VI., page 135). Although actively engaged in business all his life, Sharpe communicated several papers to the Geological Society, his researches into the origin of slaty cleavage being among the ablest and most important of his contributions to geology ("Quart. Journ. Geol. Soc." Volume III., page 74; Volume V., page 111). A full account of Sharpe's work is given in an abituary notice published in the "Quart. Journ. Geol. Soc." Volume XIII., page xlv. -on elevation. -Darwin meets. -letters to. -on cleavage and foliation.

Sharpey, W., letter from Falconer to. -Honorary member of Physiological Society.

Shaw, J., letter to.

Sheep, varieties of.

Sheldrake, dancing on sand to make sea-worms come out.

Charles Darwin

All Pages of This Book