Astronomy, Halley’s discoveries in connection with, 226 Newton’s discovery of law of gravitation as affecting, 230 photography as affecting study of, 222 spectroscope as affecting study of, 224, 225 Atavism, feeble-mindedness resulting from, suggestion as to, 274 Athletes, experiments as to possible use of pure oxygen by, 260-263 Auzout, M., astronomical predictions attempted by, 229, 230 Bacon, Lord, quotation from, 1, 14 Bacteria, destructive invasion made by, 340 microscopic observation of, improvement in, 239 Balfour, Rt. Hon. Arthur, speech at Manchester by, 6, 7 (quotation) Bananas, cultivated varieties of, 369 plantains and, identity of, 368 Bayeux tapestry, 231 Becquerel, M., experiments of, 183 Beetles, book-worm, depredations of, 350-351 death-watch, tapping made by, 351, 352 wood-boring, 351, 352 wood-boring, 349-350 lady-bird, beneficial activity of, 319, 325, 326 origin of name, 325 perforation of soft metal by grubs of, 353 Bell-animalcules, 197 Birth-rate, increased, amongst poorer classes, 285, 286 Blood, lack of red colour in, cause of, 148, 149 red-coloured, cause and special duty of, 148 Bonaparte, Prince Roland, French representative at Darwin Centenary Celebration, 39 Book-worm beetle, 350 Boulenger, Charles, Egyptian fresh-water jelly-fish described by, 64 Boys, C. V., fine quartz threads spun by, 294, 295 Caddis-worms, movable cases made by grubs of, 343 Calandruccio, discovery of young of the eel by, 71-72 Cambridge—Darwin Centenary Celebration, Address by Sir Ray Lankester at, 33-37 held at, 18, 33, 38 notable representatives at, 33, 38, 39 Cave-men, ancient, artistic skill of, 80, 81 horse mastered and muzzled by, 80, 81 Caves, care taken in excavation of, 388 discoveries of human remains in deposits of, 371, 374, 383, 393, 395, 402, 407-409 discovery of bones of ancient men in, rarity of, 372-374 French and English, evidences of human occupation found in, 78-79 Cells, definition and origin of term, 170-173, 328 egg-cell, process of fertilisation, 202-204, 330, 332 important part played by nucleus in life of, 198-200, 328, 329 individual character and co-ordinated activity of, 170, 180-182, 184, 328 process of division, 200-202, 328 “Cell-theory,” explanation of Professor Schwann’s, 174-176 Chapelle-aux-Saints, discovery at, important, 371, 374, 390, 402 Children, feeble-minded, number attending schools provided for, 278 result of neglect to provide supervision for, 279-281 China, introduction of opium smoking into, 366, 367 Chinese primrose, similarity between poisonous properties of _Rhus toxicodendron_ and, 104