Shells, Forbes and Hancock on British. -distorted by cleavage. -means of dispersal. -protective colour of.
Sherborn, C.D., "Catalogue of Mammalia" by A.S. Woodward and.
Shetland, comparison between flora of T. del Fuego and that of.
Shrewsbury, school.
Siberia, Rhinoceros and steppes of central.
Sicily, elephants of. -flora of.
Sidgwick, Prof. H.
Siebold, von.
Sigillaria, an aquatic plant.
Silene, Gartner's crossing-experiments on.
Silurian, comparison between recent organisms and. -life of. -Lingula from the. -corals. -volcanic strata.
Simon, Sir John: he was for many years medical officer of the Privy Council, and in that capacity issued a well-known series of Reports. -reports by.
Simple forms, existence of. -survival of.
Simpson, Sir J., on regeneration in womb.
Siphocampylus.
Sitaris, Lord Avebury on Meloe and.
Siwalik hills.
Skertchley, S.B.J., on palaeolithic flints in boulder-clay of E. Anglia. -letter to.
Skin, influence of mind on eruptions of.
Slate, cleavage of schists and.
Slave-ants, account in the "Origin" of.
Sleep, plants' so-called.
Sleep-movements, in plants. -of cotyledons.
Slime of seeds.
Sloths.
Smell, Ogle's work on sense of.
Smerinthus populi-ocellatus, Weir on hybrid.
Smilaceae, reference to genera of.
Smilax, De Candolle on flower of.
Smith, Goldwin.
Smith, J., note on.
Snails of Porto Santo.
Snipe, protective colour of.
Snow, red. -geological action of frozen.
Snowdon, elevation in recent times.
Social instincts, actions as result of.
Social plants, De Candolle on. -in the U.S.A.
"Sociology," H. Spencer's.
Soda, nitrate beds.
Soil, in relation to plant distribution.
Solanaceae.
Solanum rostratum, Todd on stamens of.
Solenhofen, bird-creature from.
Sollas, Prof., director of the Funafuti boring expedition. -account of the boring operations by.
Sonchus, introduced into New Zealand.
Song, importance in animal kingdom.
Sophocles, Prof., on expression of affirmation by Turks.
Sorby, on metamorphism.
Sound, and music.
Southampton, British Association meeting (1846). -Darwin on gravel deposits at. -Darwin's visits to.
Spanish chesnut, variation in leaf divergence.
Spanish plants in Ireland. -in La Plata.
Spawn, dispersal of frogs'.
Spean, terraces in valley of.
Special ordination.
Specialisation.
Species, antiquity of plant-. -belief in evolution of. -changing into one another. -creation of. -Darwin recognises difficulties in and objections to his views on. -definition of. -descriptive work influenced by Darwin's views on. -facts from Hooker bearing on. -food as important factor in keeping up number of. -frequency of. -Asa Gray on. -Hooker on. -intermediate forms absent in close. -little tendency during migration to form new. -modification of. -and monstrosities. -mutability of. -Nageli's views on. -origin of (see Origin of Species). -permanence of. -Prichard on meaning of term. -range of. -representative. -separate creation of. -spreading of. -sterility between allied. -and sterility. -time necessary to change. -time of creation of new. -variation of. -Wallace on origin of. -Walsh on modification of. -Weismann on. -Gaudry on affiliation of. -Hackel on change of. -isolation of. -value of careful discrimination of.
"Species not transmutable," Bree's book on.
Specific character, Falconer on persistence of.
Speculation, Darwin on.
Spencer, H., Darwin on the advantage of his expression "survival of the fittest." -letter to. -on electric organs. -on genesis of nervous system. -on survival of the fittest. -Romanes on his theory of nerve-genesis. -Wallace's admiration for. -Darwin on his work. -extract from letter to. -mentioned.
Spermacoce.
Spey, terraces of.
Sphagnum, parasitism of orchids on.
Spiders, mental powers of. -Moggridge on.
Spiranthes, fertilisation of.
Spiritualism, Darwin on.
Sptizbergen, Lamont's book on. -reindeer of.
Sponges, Clark on classification of. -Hackel's work on. -F.