Bees, amount of their susceptibility of pain, 57. construction of cells, 327. duties performed in the hive, 325. duties transferable, 336. early cultivated, 3, 90, 91. economy, early known, 92. emit an odour, 52. enemies, 51. extent of flight, 340. flight, modes of, varies, 49. found in the Orkneys, 7. genera of, determined by an artificial mode, 170. habits of, in America, 7. hairiness of, reason of, 14. intimately connected with flowers, 3. largely contribute to the impregnation of plants, 11. make about ten journeys a day, 351. many disclosed in autumn for the following year’s spring flight, 53. not early risers, 51. number of eyes, 355. other than social, also known, 8. rarely walk, 50. sagacity in finding the honey of flowers, 13. scientific arrangement and description of the genera of, 184. secretion of wax, 325. stages of life of,— egg, 18. larva, 19. pupa, 22. imago, 23. swarming, 337. their relative perfection, 56. voice, a scale of music, 49. Beehive represented on a tomb at Thebes, 6. Beehives moved on rafts, 84. Bifid, divided into two parts. Binomial system invented by Linnæus, 129. Body of the bee, its structure, 25. Bombus, difficulty in determining the species of the males, 311. general observations on, 310. geography of, 78. infested by _Apathus_, 311. list of native species, 308. natural history of, 312. peculiarities in times of appearance, 312. scientific description of, 307. Boss of mesothorax, 45. Bougie, derivation of, 84. British bees, new arrangement of, 153, 158. Carder-bees, 316. Carelessness of describers of new species, 125. Carinated, having a longitudinal elevated line. Carpenter bees, 286. Cells of hive, geometrical form of, 343. results from instinct, 343. how constructed, 342. of wings characteristic, 44. Cenobites = social bees, 167, 302. Ceratina, disputed parasitism of, 247. general observations on, 246. geography of, 71. list of native species, 246. natural history of, 247. scientific description of, 245. Cereal plants early cultivated, 4. Chelostoma, general observations on, 286. geography of, 76. infested by Fœnus, 287. native species of, 285. natural history of, 286. scientific description of, 283. Chrysis infests Chelostoma, 287. infests Halictus, 219. infests Osmia, 302. Cibarial apparatus = trophi = collective organs of the mouth, 163. Cilissa, general observations on, 213. geography of, 67. list of native species, 213. scientific description of, 211. Clavate, club-shaped. antennæ, 28. Claws, 42. reflected, 285. Climate inoperative on low forms of life, 24. Clothing of bees, 60. Clypeus, 26, 28. Coadunate, closely united without perceptible articulation.