isher's, ii. 74

Physiological selection (_see_ Selection, physiological)

Pickard-Cambridge, Rev. O., reminiscences of Wallace, ii. 131

Pictet, Prof. F.J., reviews the "Origin of Species," i. 141, 144

Pigeons, domestic, i. 130

"---- of the Malay Archipelago," Wallace's, i. 166, ii. 4

"Plants, Crossing," Darwin's, Wallace on, i. 296-7

---- geographical distribution of, i. 94;
effect of climatic conditions on, 130;
heterostyled, 298;
migration of, 307 (note), 310, 311-12, 313-14, ii. 32, 34-5;
Lyell on migration of, 19-20;
variety of form and habit in, 54

"Plants of India and Indo-Oceanic Continent," Blandford's, i. 290

Pleistocene Period, i. 308

Pliocene Period, i. 292, 294, ii. 22

Podmore, Frank, effect on, of Hodgson's Psychical Research report,
ii. 203;
report by, in _Proceedings_ of Psychical Research Society, 204;
proposed as President, 211

Polymorphism, Wallace on, i. 168

"Population, Essay on," Malthus's, i. 103, 104, 111, 116, 136, 175, 317

"---- Theory of," Spencer's, i. 124

Poulton, Prof., and Weismann's "Essays upon Heredity," ii. 44-6;
paper on colours of larva, pupa, etc., 54;
appointed Hope Professor of Zoology in Oxford University, 57;
exposure of an American Neo-Lamarckian by, 60;
Presidential Address to British Association, Wallace's criticism of, 71;
Presidential Address to Entomological Society, 79;
on Wallace, 227;
at funeral of Wallace, 252;
and the Westminster Abbey memorial, 253

Poverty, Wallace's views on, ii. 145 _et seq._

"Power of Movement in Plants," Darwin's, i. 311, ii. 2

Prain, Sir D., and Wallace memorial in Westminster Abbey, ii. 253

"Prehistoric Times," Lubbock's, i. 164, 165-6

"Present Evolution of Man, The," Archdall Reid's, ii. 67, 73

Price, Prof. B., formally offers D.C.L. degree to Wallace, ii. 217

Prichard's "Physical History of Man," i. 91, 116, ii. 73

Primula, Darwin's paper on, i. 218

"Principles of Geology," Lyell's, i. 135, ii. 5

"---- of Psychology," Spencer's, i. 123

"---- of Sociology," Spencer's, i. 126

Proctor, R.A., i. 263; "Expanse of Heaven," ii. 180

"Progress and Poverty," Henry George's, i. 317, 318, ii, 143

Protection, principle of, i. 140, 177, 184, 186, 189, 192, 199, 205,
212 _et seq._, 214 _et seq._, 220, 221, 222, 223, 224,
226 _et seq._, 235-6, 252, 256, 257-9, 270, 291, 299-300
(_see also_ Coloration, protective, _and_ Mimicry)

"Protective Rese