424 



INDEX 



Eye, compound, 30 ; 



defects in, 361 ; 



section of, 360. 

 Eyestrain, 395. 



Factory inspection, 379. 

 Fallowing, 82. 

 Fatigue, 326 ; 



and nerve cells, 356. 

 Fats and oils, 60, 273. 

 Fehling's solution, 68, 299. 

 Fermentation, 135, 136, 150. 

 Fertilization, of fish eggs, 240 ; 



of flower, 54. 

 Fibers, vegetable, 127. 

 Fibrin, 315. 

 Fibrinogen, 315. 

 Fig insect, 43. 

 Filament, 36. 



Filter beds at Albany, N. Y., 385. 

 Fins, 233. 

 Fishes, 186; 



artificial propagation, 240 ; 



as food, 201 ; 



body of, 232 ; 



breathing, 234 ; 



circulation, 236, 321 ; 



digestive system, 235 ; 



egg-laying habits, 238 ; 



food getting, 234 ; 



food of, 237 ; 



gills, 234 ; 



heart, 236 ; 



migration, 238 ; 



nervous system, 237 ; 



skeleton, 237 ; 



senses, 233 ; 



swim bladder, 236. 

 Fission, 170. 



Flagella of bacteria, 142. 

 Flatworms, 183. 

 Flax, 128. 

 Flea, 225. 



Floral envelope, 35. 

 Flower, fertilization of, 54; 



lengthwise section, 35; 



use and structure, 35. 

 Fluid, 181. 

 Fly, a disease carrier, 222; 



Fly, foot of, 223 ; 



life history, 222 ; 



typhoid, 223. 

 Foods, absorption of, 309 ; 



adulteration, 288 ; 



amphibia as, 202 ; 



birds as, 202 ; 



cost of, 283 ; 



fish as, 201 ; 



fruits and seeds, 119; 



getting of fish, 234 ; 



in cotyledons, 60 ; 



inorganic, 274 ; 



inspection, 380 ; 



is alcohol a food, 289 ; 



leaves, 117, 118; 



making in green leaf, 93 ; 



mammals as, 202 ; 



of animal origin, 279 ; 



of bacteria, 144 ; 



of fishes, 237; 



of insects, 33 ; 



of plant origin, 278 ; 



of starfish, 216 ; 



reptiles as, 202 ; 



roots as, 119; 



stems as, 118 ; 



taking, 181 ; 



tube of frog, 243 ; 



values, tables, 276 ; 



waste in kitchen, 287 ; 



why we need, 272. 

 Foraminifera, 182. 

 Forestry, 113. 

 Forest destruction, 112, 113; 



fires, 112; 



of North Carolina, 105 ; 



other uses, 109 ; 



protecting, 114 ; 



regions of United States, 109. 

 Formaldehyde, 148. 

 Formation of habits, 354. 

 Four o'clock embryo, 103. 

 Fresh air, 337. 

 Frog, adaptations for life, 2-11 ; 



and man, digestive trad, 297; 



breathing, 242 ; 



circulation, 243, 322 ; 



development of, 244 ; 



