Essays, 124;
  appreciation of Wallace’s magnanimity, 134, 137, 139, 141, 153,
    164, 242, 252, 287, 304;
  falls from his horse, 243;
  on Wallace’s review of “Descent of Man,” 260-2;
  criticism of Wallace’s “Geographical Distribution,” 286, 289;
  at Dorking, 288;
  promotes memorial to City Corporation in favour of Wallace, 303;
  acknowledgment of “Island Life,” 307-8;
  on migration of plants, 307 (note), 312;
  memorial to Gladstone on behalf of Wallace, 313;
  death of, 318

Darwin, Charles, letters to Wallace: 
  On “Law regulating Introduction of New Species,” etc., i. 106, ii. 129;
  on distribution of animals, i. 133;
  on his “Origin of Species,” etc., 134, 136;
  on Wallace’s “Zoological Geography of the Malay Archipelago,” 137;
  inviting Wallace’s opinion of the “Origin,” 139;
  on protective adaptation of butterflies, 140;
  on Press reviews of “Origin,” 141, 144;
  on theory of flight, 146;
  on Wallace as reviewer, 148;
  on Wallace’s “Variation” and his paper on Man, 153;
  on sexual selection, 159;
  on Wallace’s papers on pigeons and parrots, 160;
  on the Aru pig, 162;
  on the crested blackbird, etc., 163;
  on Wallace’s “Pigeons of Malay Archipelago” and dimorphism, 166;
  on the non-blending of varieties, 169;
  on the term “survival of the fittest,” 174;
  on sexual differences in fishes, 177;
  on colour of caterpillars, 178;
  on coloration and expression in man, 179;
  on sexual selection and expression, 182;
  on scheme for his work on Man, 183;
  on laws of inheritance, etc., 185;
  on Wallace’s “Mimicry,” 187;
  on Wallace’s reply to Duke of Argyll, 189;
  on sexual selection and collateral points, 194;
  on pangenesis and sterility of hybrids, 197;
  on production of natural hybrids, etc., 201;
  on sexual selection, 204, 206, 207;
  on northern alpine flora, 211;
  on Wallace’s article on “Birds’ Nests,” and on mimetic butterflies, 212;
  on Sir Clifford Allbutt’s sperm-cell theory, and on female protected
    butterflies, 214;
on Wallace’s “Protective Resemblance,” 216;
  on dimorphic plants and colour protection, 220;
  on the colour problem of birds, 225, 229, 231;
  on fifth edition of “Origin of Species,” 233;
  on single variations, 234;
  on Wallace’s “Malay Archipelago,” 235, 237, 240;
  on Wallace’s review of Lyell’s “Principles,” 242;
  on baffling sexual characters, 245;
  on Wallace’s paper, “Geological Time,” 250;
  on Wallace’s views on Man, 250, 251;
  on Wallace’s “Natural Selection,” 252;
  on Wallace’s criticism of Bennett’s paper, 253;
  on his “Descent of Man” and St. G. Mivart, 257;
  on Wallace’s review of “Descent of Man,” 260;
  on Chauncey Wright’s criticism of Mivart, 264;
  on a Quarterly review, 269, 291;