874 Index 



Diastase, 476 



Diastole, 478 



Diatom, 116, 117,* 154, 159, 160, 249 



Diatomaceous earth, 160, 250 



Dicotyledoneae, 110, 143-148, 207, 211, 



213 

 Diecious, 164, 186, 189, 200, 202, 203, 



295, 382 

 Differentiation, 46, 94, 95, 241, 242, 



683 

 Diffraction, 759 



Diffusion, 39, 80, 100, 730, 754 

 Digestion, 344, 352, 369, 388, 472-477 



{see also specific organisms) 

 Digit, 333, 425 



Dihybrid cross, 686-690, 686,* 689* 

 Dimorphism, 381 

 Dinosaur, 608* 

 Dioscorides, 801 

 Diphvllobothrium, 537 

 Diploid, 162, 206, 207, 357, 679, 680, 



709 

 Diploplastic, 280, 286 

 Diplopoda, 318, 324,* 544 

 Disaccharide, 87 

 Discontinuous variation (mutation), 



724 

 Diseases caused by animals, 660, 661, 



784-789 

 by fungi, 252-254, 253,* 659, 660 

 by plants, 659, 789 

 by viruses, 789-790 

 human, 516-522, 659, 784-786 

 Disk, 189, 216, 286,* 291,* 297, 302, 



303, 699 

 Dispersal, 76, 78, 593, 655, 656 

 Distomum {see Liver fluke) 

 Distribution, 591-604, 593* 

 Divergence, 729, 827 

 Diverticulum, 308,* 328,* 369, 371* 

 Division of labor, 828 

 Dizygotic, 828 



Dobson fly, 562* {see also Insects) 

 Domestication, 638 

 Dominance, 682-692 

 Dominant and recessive traits, 682-692 

 Dorsal horn, 55* 

 Dourine in horses, 786 

 Dragonfly {see Insects) 

 Drone, 399, 399* 

 Drosophila {see Fruitfly) 

 Drugs, 269 

 Duct of Cuvier, 741* 



of Wirsung, 477 

 Ductless glands (endocrine), 495,* 



506-513, 507* 

 Dugesia {see Planaria) 

 Dujardin, 31, 37 

 Duodenum, 340,* 426, 427,* 429, 470,* 



473, 509, 512 



Dura mater, 503 

 Dyes, 263 

 Dynamic, 100 

 Dysentery, 784 



E 



Ear, 146,* 439, 495, 498,* 505 

 Early man and records, 585-590, 587* 

 Earthworm, 309, 384-392, 385,* 540 

 Earwig, 562* {see also Insects) 

 Eberthella typhosa, 121,* 255 

 Ecdysis, 393, 398 

 Echinococcus, 537, 788 

 Echinodermata, 299-304, 300,* 540 



regeneration of, 98, 98* 

 Echinoidea, 303, 303,* 305* 

 Ecology, 24, 620-645, 723 

 Economic botany, 249-271 



beverages, 264-266 



coloring (dyes), 263 



cork, 261 



fibers, 260 



flavoring substances, 266 



foods, 264 



fuels, 258, 259 



gums and resins, 262, 268 



medicines and poisons, 267-270 



oils, 259, 267 



savory substances, 267 

 zoology, 530-575 



insects {see Insects) 

 Ectoderm, 280, 286, 286,* 287, 288,* 

 291,* 292, 293, 295, 299, 306, 

 309, 314, 325, 368, 373, 445,* 

 449,* 454 



Ectoparasite, 653 



Ectoplasm (ectosarc), 39, 40,* 345,* 



349 

 Efferent nerve, 494, 497 



vessel 322* 

 Egg (ovum), 134,* 136, 136,* 140,* 



143, 154, 161, 162, 163,* 



164, 174,* 175, 188, 189, 



194-197, 201-203, 361,* 363, 



396,* 398, 406, 410 

 sac, 225,* 317,* 389,* 391* 

 Ejaculatory duct, 380,* 382, 398, 406, 



513 

 Elasmobranchii, 329, 331 

 Elater, 136, 137,* 189, 195 

 Electricity, 77, 353,* 647, 746-766 

 Electrocardiogram, 479 

 Electrolyte, 84, 751 

 Electron, 79,* 81, 81,* 83* 



microscope, 32, 34,* 35 

 Elements, 78, 79,* 80, 85 

 Elephantiasis, 297, 297,* 298, 539, 661, 



785 

 Elodea, 40* 



