440 



INDEX 



Dandelion, 86 ; 



leaves of, 118. 

 Decay by bacteria, 177. 

 Deliquescent tree, 100. 

 Dermis, 321. 

 Development, of bee, 254 ; 



of crayfish, 226 ; 



of fly, 241 ; 



of frog, 288, 289, 290 ; 



of lobster, 227 ; 



of moth, 239. 

 Diaphragm, 357 ; 



in respiration, 384. 

 Diastase, action of, 72. 

 Diatoms, 149. 

 Dichogamy, 48. 

 Dicotyledons, 73. 

 Dietary, best, 333. 

 Digestion, 352 ; 



and absorption, 352 ; 



effect of alcohol on, 364 ; 



in corn grain, 71 ; 



in crayfish, 225 ; 



in fishes, 278 ; 



in plants, 106 ; 



of starch, 356 ; 



organs of, 206, 362 ; 



purpose of, 352. 

 Digestive tract in frog, 287. 

 Dipnoi, 284. 

 Diptera, 240, 241, 242, 247 ; 



prevention of, 418. 

 Disease of nose and throat, 389. 

 Diseases, due to insects, 258, 259, 

 260; 



infectious, 430. 

 Division of labor, 199 ; 



in hydra, 203 ; 



in vorticella, 195. 

 Dragon fly, 244. 

 Drone, 264. 



Drugs, use and abuse of, 349. 

 Dusting, 387. 



Dyspepsia, causes and prevention 

 of, 363. 



Ear, human, 408. 



Earthworm, development of, 215 ; 



locomotion in, 214 ; 



relation to surroundings, 212. 



Eating, hygienic habits of, 363. 

 Economic importance, of alcoholic 

 poisoning, 416 ; 



of birds, 304 ; 



of carnivora, 313 ; 



of corals, 210 ; 



of earthworms, 215 ; 



of ferns, 156 ; 



of food in roots, 95 ; 



of insects, 261, 262, 263, 264, 265 ; 



of leaves, 128 ; 



of lobster, 228 ; 



of moUusks, 269, 271 ; 



of parasitic worms, 219 ; 



of plants, 170 ; 



of roots and stems, 109 ; 



of snakes, 295 ; 



of starfish, 272 ; 



of trees, 133, 135. 

 Ectoderm, defined, 200. 

 Egg, development of, 200. 

 Egg cell, 37, 153, 155, 227, 280, 288. 

 Egg-laying habits of fishes, 280. 

 Elasmobranch, 283, 284. 

 Embryo sac, 36, 156. 

 Endoderm, defined, 200. 

 Endoskeleton, 275, 279. 

 Endosperm, use of, 69, 72. 

 Energy, defined, 20. 

 Entomostraca, 231. 

 Environment, 17. 



Enzyme, action upon fibrinogen, 

 367; 



in saliva, 357. 

 Enzymes, 72, 353 ; 



in blood, 366, 367 ; 



in gastric juice, 358 ; 



reversible action of, 366. 

 Epicotyl, 65. 

 Epidermis, 321. 

 Epiglottis, 354. 

 Erosion, by streams, 133, 134 ; 



prevented by organic covering, 



135. 



Esophagus, 352, 354, 357. 

 Eustachian tube, 354, 408. 

 Excretion, effect of alcohol upon, 

 397; 



in crayfish, 226 ; 



organs of, in man, 390, 



