Podostemaceae, fertilisation of.
Poisons, natives of Australia injured by vegetable. -absorption by roots of. -effect of injection into plants.
Polar bear, modification of.
Polar ice-cap, Darwin on the.
Polarity, E. Forbes' theory of.
Pollen, direct action of. -experiments on. -time of maturity in Eucalyptus and Mimosa. -mechanism for distribution in Martha. -Miyoshi's experiments on tubes of.
Polyanthus, crossing in.
Polyborus Novae Zelandiae, in Falkland Islands.
Polydactylism, and inheritance.
Polyembryony, in Coffea and Pachira.
Polygala. -P. vulgaris, variation of.
Polygamy, in birds. -in Machetes.
Polygonum, germination of seeds found in sandpit.
Polymorphism, Darwin and Hooker on. -Wallace on.
Polytypic genera, variation of.
Pontederia, heterostylism of.
Pontodrilus, Lankester on.
Poplar, Heer on fossil species.
Popper, J., letter to.
Poppig, on civilisation and savagery.
Poppy (corn-), indigenous in Sicily.
Porpoises, Flower on. -freshwater. -Murray on.
Portillo Pass.
Porto-Santo, land-snails of. -plants of.
Positivism, Huxley's article in "Fortnightly Review" on.
Posoqueria, F. Muller's paper on.
Potatoes, crossing experiments. -cultivated and wild. -disease of. -experiments suggested. -graft-hybrids. -sterility and variability in. -Torbitt's experiments on. -Traill's experiments. -varieties of. -Darwin's work on varieties of. -Hildebrand's experiments on.
Poulton, Prof., on Prichard as an evolutionist. -"Charles Darwin and the Theory of Natural Selection."
Poultry, skulls of. -Tegetmeier's book on. -experiments on colour and sexual selection.
Powell, Prof. Baden.
"Power of Movement in Plants," Darwin's account of capacity of revolving in plants, in his book. -Continental opinion of. -Wiesner's criticism of.
Prawns, F. Muller on metamorphosis of.
Prayer, Galton's article on.
Pre-Cambrian rocks, Hicks on.
Predominant forms.
"Prehistoric Europe," J. Geikie's.
"Prehistoric Times," Lord Avebury's.
Preordination, speculation as to.
Prepotency of pollen.
Prescott, reference to work by.
Preservation, suggested as an alternative term for Natural Selection.
Pressure, effect on liquefaction by heat.
Preston, S. Tolver, letter to.
Prestwich, Prof. J., letter to. -on Parallel Roads of Glen Roy. -on superficial deposits of S. England. -work on Tertiaries. -mentioned.
Prevost, C., as candidate for Royal Society Foreign List. -mentioned.
Price, J., extract from letter from Darwin to.
Prichard, James Cowles (1786-1848): He came on both sides from Quaker families, but, according to the "Encyclopaedia Britannica," he ultimately joined the Church of England. He was a M.D. of Edinburgh, and by diploma of Oxford. He was for a year at Trinity College, Cambridge, and afterwards at St. John's and New College, Oxford, but did not graduate at either University. He practised medicine, and was Physician to the Infirmary at Bristol. Three years before his death he was made a Commissioner in Lunacy. He not only wrote much on Ethnology, but also made sound contributions to the science of language and on medical subjects. His treatise on insanity was remarkable for his advanced views on "moral insanity." -on immutability. -quotations from his "Physical History of Mankind."
Priestley, "Green matter" of. -Huxley's essay on.
Primogeniture, antagonistic to Natural Selection.
Primrose (see also Primula), Darwin's experiments on cowslip and. -dimorphism of. -J. Scott on.
Primula, Darwin's work on. -difficulty of experimenting with. -dimorphism of. -dimorphism lost by variation. -entrance of pollen-tubes at chalaza. -varying fertility of. -fertilisation of. -homomorphic unions and. -ovules of. -J. Scott's work on. -stamens of. -P. elatior. -P. longiflora, non-dimorphism of. -Treviranus on. -P. mollis. -P. scotica. -P. sinensis. -fertility of. -legitimate and illegitimate unions. -movement of cotyledons.
Principle of divergence.