Dipterous gall fly, 196. Dipterous larvae, 175. Dohrn, Anton, on ancestry of insects, 169. Dragon fly, 106, 171, 195. Dujardinia, 170. Dytiscus, 182. Ear wig, 136. Echinoderes, 169. Egg parasites, 201. Egg parasite of Agrion, 164. Eggs of canker worm, 187. Elm tree insects, 90. Embryology, comparative. 167. Embryology of Podura, 140. Ennomos, 216. Ephemera, 154, 194. Ephydra, 174. Eruciform larva, 175. Euphorberia, 158. Evolution theory, 152. Eyes of insects, 185. Fabre on hyper-metamorphosis, 43. Fall weaver, 197. Fire fly, 202. Flea, 86. Forceps Tail, 171. Forficula, 136. Fossil insects, 158. Myriopods, 158. Scorpion, 158. Foul brood, 40. Gad fly, 74. Galley worm, 149. Gall flies, 193. Gall fly, 72, 203. Gall fly, two-winged, 196. Gamasus, 120. Ganin on embryology of insects, 161. Gegenbaur on tracheae, 172. Generalized types, 154. Generation, alternate, 168. Gerris, 210. Gerris, egg-parasite of, 166. Gills of insects, 172. Gnat, 71, 189. Gonocerus, 204. Gordius, 46. Gortyna, 215. Grain Aphis, 209. Grape insects, 57. Grape leaf roller, 205. Grape saw fly, 207. Grapta, 189, 204, 207. Grasshopper, 181, 211. Green head, 74. Grimm on parthenogenesis, 168. Haeckel, Ernst, on ancestry of insects, 156. Hairs of insects, 185. Hair worm, 46. Halictus, 31, 192. Handily, A. H., on Thysanura, 133. Hartt's discovery of fossil insects in New Brunswick, 158. Harvest bugs, 122. Haustellate insects, 183. Hawk moth, 194, 200. Head of insects, mode of formation of, 174. Heart, iv. Hemiptera, 209. Hemipterous larvae, 175. Hessian fly, 72, 196. Heteropus, 126. Hibernation of insects, 192. Hirudo, 166. Histolysis, 168. Histriobdella, 166. Histriobdella stage of Polynema, 164. Hop vine moth, 215. Horse tick, 84. House fly, 80. Humble bee parasite, 215. Humming bird moth, 194. Hunt on organic life in the Laurentian period, 158. Hylobius pales, 188. Hylurgus terebrans, 188. Hymenopterous larvae, 175. Hyper-metamorphosis of insects, 166. Hyphantria, 204. Hypodermis, 163. Ichneumon, 161, 201. Illinois, fossil insects of, 159. Ilythia, 215. Injurious insects, 190. Insects, ancestry of, 150. Insects, archetypes of, 150. Insects, beneficial, 190. Insect calendar, 187. Insects, embryology of, 154, 155. Insects, flight of, ix. Insects in the Devonian formation, 158. Insects, metamorphosis of, 166. Insects, origin of, 156. Insects, reason in, 30, 37. Insects, respiration of, 171. Insects, senses of, xiii. Insects, sexes in, 52. Insects, transformations of, xiv, 50. Insects, wingless, 171. Intestinal worms, 161. Isotoma, 140, 143. Itch mite, 125. Ixodes, 117, 123. Japyx, 132. Jaws of insects, origin of, 174. Jelly fishes, 168.