Galactans, 47, 59, =63=, 72. Galactoheptose, 36. Galactooctose, 36. Galactose, 32, 36, 38, 45, =47=, 57, 72, 77. Galactosides, 41, 42. Gaultherin, 81. Gel, 172, 205, 208. Gelation, 210. Gel-formation, =208=, 211. Gentianose, 52, =53=. Gentiobiose, 49, =52=, 53. Gentisin, 119. Gitaligenin, 89. Gitalin, =89=. Gitogenin, 89. Gitonin, =89=. Glaucophyllin, 107. Gliadin, 165, 170, 176. Globulins, 170, 175, 176. Glucase, 186. Glucodecose, 44. Glucoheptose, 36, 44. Glucononose, 36. Glucooctose, 36. Glucoproteins, 175. Glucose, 23, 28, 32, 36, =37=, 40, 41, 42, 43, 44, 45, 46, 57, 77. Glucosidases, 189. Glucosides, 18, 20, 41, 48, 55, =76=, 91, 93. Glue, 210. Glutelins, 175, 176. Glutenin, 176. Glycerine (_see_ glycerol). Glycerol, 129, 131, =134=, 142. Glycine, 166, 168, 177. Glycinin, 176. Glycogen, 59, =61=. Glycyphyllin, =79=. Graminin, 59, =62=. Granulose, 60. Grape sugar (_see_ glucose). Guanase, 190. Guanine, =160=, 162. Gulose, 36, 37. Gum arabic, =68=. Gums, 62, 67, =68=. Gum tragacanth, =69=. Gun-cotton, 73. Hæmatin, 110. Hæmatinic acid imide, 109. Hæmatoporphyrin, 110. Hæmoglobin, 110. Hæmopyrrole, 109. Helicin, 81. Hemi-celluloses, 63, =71=. Hemi-terpenes, 147. Heptoses, 30. Hesperidin, =79=. Hesperitin, 79, 80. Heterotrophic plants, 16. Hexosans, 59, 67. Hexoses, 22, 28, 30. Histidine, 169, =177=. Histones, 175, 176. Honey sugar (_see_ fructose). Hordein, 153, 170, 176. Hormones, 92, 239, =240=. "Hot-drawn oils," 137. Humins, 67. Hydrastine, 155. Hydrazones, 40, 49. Hydrocellulose, 73. Hydrogen peroxide, 26, 27, 190. Hydrogel, 205. Hydrolases, 186, 189. Hydroquinone, 77, 79. Hydrosol, 205. Hydroxy-phenyl ethyl amine, 153. Hygrine, 155, 156. Hyoscine, 155. Hyoscyamine, =156=. Hypoxanthine, =160=. Idain, =85=. Idose, 36, 37. Illuminating gas as a toxin, 247. Imbibition, 209. Impermeable membranes, 228. Indian yellow, =84=. Indican, 78, =85=. Indigo, 78, 84. Indigotin, 85. Indole, 158. Indoxyl, 85. Inhibitors, 196. Intracellular enzymes, 184. Inulin, 59. Inulinase, 62, 189. Invertase, 50, 189, =191=. Invert sugar, 47, 50. Iodine number, 138. Ionization phenomena, 226. Iridin, =79=. Irigenin, 79, 80. Iron, 3, 5, 11, 110. Isochlorophyllin _a_, 106, 107, 108. Isochlorophyllin _b_, 106, 107, 108. Isohæmopyrrole, 109. Isoleucine, 168. Isomaltose, 51. Isomerism, 32. Isoprene, 147. Isoquercitrin, 84. Isoquinoline, 155. Jalapin, =81=. Japan wax, 129. Juglansin, 176. Ketose, 32.