Chapter 22

---- ---- ---- letter to Mr. Theo. D.A. Cockerell, on fertilisation, ii. 49

---- ---- ---- letters to Charles Darwin: on the Timor honeycomb, i. 143; on Darwin's "Orchids," 143; on theory of flight, 145; on Spencer's "Social Statics," 150; on Borneo exploration and his contribution to theory of man's origin, 152; on his paper on Man and Natural Selection, 155; on the Aru Islands, 161; on a case of variation becoming hereditary, 162; on the _Reader_, 165; on dimorphism, 168; suggesting "survival of the fittest" in preference to "natural selection," 170; on mimicry and glacier action, 176; on expression, 180; on "Creation by Law," 188, 192; on superintendency of a Museum, 193; on sterility of hybrids, 196; on natural selection as producing sterility of hybrids, and pangenesis, 199; on Trimen's paper at the Linnean Society, 201; on selective sterility, 203, 205, 210; on Darwin's "Cross Unions of Dimorphic Plants," 218; on protection and sexual selection, 221, 222, 227; on the dedication of "Malayan Travels," etc., 232; on single variations, 234; on colouring of caterpillars, 235; on his "unscientific" opinions on Man, 243, 250, 255; on wing-scales of butterflies, 244; on Dr. Meyer, 248; on "Descent of Man," 255, 259, 284; recommending two remarkable books, 263; on Mivart and Chauncey Wright's critique, 265; on Darwin's answer to Mivart, 271; on Dr. Bree, and Bastian's "Beginnings of Life," 273; on a Bethnal Green Museum appointment, 277; on Darwin's "Expression of the Emotions," 279; on invitation to undertake revision work for Darwin, 281, 282; on "Climbing Plants," 285; on Darwin's criticism of "Geographical Distribution," 288, 294; on Darwin's "Crossing Plants," 296; on Darwin's "Orchids," 297; on Darwin's "Forms of Flowers," and glacial theory, 298; on sufficiency of Natural Selection, 300; on Epping Forest superintendency, 302, 303; on "Island Life," 305, 306; on Darwin's criticism of "Island Life," 308; on Darwin's "Movements of Plants," 311; on land migration of plants, 311; on Civil List pension, 314, 315; on "Progress and Poverty," 317; on Darwin's "Earthworms," 320

---- ---- ---- letters to Sir Francis Darwin: on Darwin's "Life and Letters," ii. 39; on descent with modification, 78; on mutation, 80

---- ---- ---- letter to Mr. W.J. Farmer, on final cause of varying colour of hairs, etc., ii. 101-2

---- ---- ---- letter to Dr. W.B. Hemsley, on insular floras, ii. 43-4

---- ---- ---- letter to Rev. J.B. Henderson, on Christianity, ii. 209

---- ---- ---- letter to Sir J. Hooker, on Natural Selection, etc.,