Aves. 65 (see Birds) 



Aviators, and breathing, 233-234 



Axon, 274-275, 274, 277; nutrition of, 275-276 



Azoic era, 533, 534 



Baby, and learning, 288-290 



Bach, Johann Sebastian, heredity of talent, 511 



Bacillus, 312, 321; coli, 312; of tetanus, 330 



Backbone, animals with, 16-39; def., 271; of man, 

 226; of snake, 28 



Backcross, 476 



Bacon, Francis, and food preservation, 384 



Bacteria, 77-78, 311-316, 330, 332; and antibiotics, 

 334; and body's defenses, 315-316; and cheese, 

 384; colonies, 314; conditions of growth, 314- 

 315; def., 311-312; digestion, 312; entry to body, 

 315; food-getting, 312; germ theory, 320-322; and 

 horse, 374; methods of identifying, 314; methods 

 of studying, 312-314; and milk supply, 345-347; 

 and nitrogen cycle, 376-378; and pasteurization, 

 346; and phagocytes, 210; of pneumonia, 78; and 

 skin disorders, 242-243; and soil restoration, 405; 

 spores, 314-315; and surgery, 331-332; types, 

 312; typhoid, 313 



Bacteriology, def., 312; and length of life, 359; and 

 study of viruses, 339 



Bacteriophage, 340-341 



Balance, sense of, 282 



Balanced aquarium, 378-379, 378 



Bamboo stems, 157 



Banana, 85 



Bark, birch, 154, 156-157; of trees, 153-154 



Barley, 84; mutation, 480 



Barnacle, 53; rock, 52 



Barriers, kinds of, 552 



Basal metabolism, 170; apparatus, 171; thyroid, 247 



Basic Seven, in diet, 182 



Bathing, 242 



Bathysphere, 6-7 



Bats, 18, 19; appendages of, 549 



BCG, vaccine for tuberculosis, 328 



"Beagle," and Charles R. Darwin, 556 



Bean, graph of lengths of, 487; seed, 438 



Bear, black, 99; polar, 99 



Beaumont, Dr. William, and gastric digestion, 193 



Beaver, dam, 264; dam-building, 262 



Beech, bark of, 153-154; purple, 137 



Bees, 48-49; drone (male), 48; kinds of, 48; life 

 cycle of, 48-49; nervous system of, 275; queen, 

 48; swarming, 48; worker, 48 



Beeswax, 48 



Beet, plant, 141; roots, 149 



Beetles, 46; Colorado potato, 46, 46; and Dutch elm 

 disease, 287; ladybird, 46; pine, 390 



Behavior, 260-308, 260; of ameba, 265; complexity 

 of, 286-289; def., 261; and emotions, 296-298; 

 examples, 261-266, 269-282, 286-298, 301-306; 

 learned, 287-296; of lower animals, 262-266; of 

 man, 286-300; of mimosa, 305; misuse of words, 

 265; and nervous system, 269-270, 286; of Para- 

 mecium, 266, 266; Pavlov's experiments, 9-10; 

 plant and animals compared, 302-303, 305; in 

 plants, 301-306; in protozoa, 265-266; unlearned, 

 262-266; of vorticella, 269 



"Bends," 233 



Benedict's solution, 116 



Benzoate of soda, 384-385 



Beriberi, 176-177, 177; 183 

 Bernard, Claude, and diabetes, 251 

 Bicuspids, 203 

 Biennials, def., 80 



Bile, 192, 195, 196, 198-199; duct, 195; salts, 197 



Binary fission (see Fission), 413 



Biological Survey, Bureau of, 406 



Biologists, 3 



Biology, def., 3 



Birch, bark, 153, 154; water loss, 159 



Bird laws, 406 



Birds, 20-26; banding, 37; bills (beaks), 23; brain 

 of, 273; calendar, 38; characteristics of, 20; clas- 

 sification of, 20-21; "family life," 431-432; flight 

 of. 23. 25; and insect control, 395-396; migration 

 of, 22-23; migration routes of, 24; names of parts 

 of, 21; nonflying, 22; perching, 22; of prey, 21; 

 reproduction of, 430-432; scratching, 21; wading 

 or swimming, 21-22 



Bird's-foot violet, 407 



Birth, in rabbit, 433 



Bismuth, and syphilis, 332 



Bison, 99; hybridization of, 501 



Black ant, 47 



Black body, in fruit fly. 472 



Black Death, 328, 343 



Blackheads. 242 



Black raspberry, vegetative reproduction of, 449 



"Blackout," of aviators, 217 



Black widow spider, 50, 51 



Bladder, 238; of frog, 422; of man, 238 



Blade, of leaf, 137-139 



Bias tula, def., 425; 425 



"Bleeders," 211; heredity of, 473 



Bleeding, first aid for, 215 



Blending inheritance, def., 467, 468; in fruit fly, 

 470 



Blister rust, of pine, 386, 386 



Blisters, 220 



Blood, 206-225; and adrenin, 252; cells, 209-210, 

 208, 210; circulation, 206-220, 218, 219; clotting, 

 210-211, 211 ; composition, 208-213 ; and diabetes, 

 250-252; donations, 212; groups, 211-212; move- 

 ment, 213-220; path, 218-220; platelets, 208, 

 209-211; sugar in, 251; table of exchange of sub- 

 stances in, 256; transfusions, 211-213; types, 211- 

 212; vessels, 206-221, 207, 213, 215, 217, 218, 

 219, 220, 221 



Blood banks, 211-212 



Blood plasma, in transfusions, 212-213 



Blood poisoning, 331-332 



Blood pressure, 216, 216-217 



Blood protein, in transfusions, 212-213 



Blood vessels, of cat's intestine, 215; of earthworm, 

 57; of frog, 207; of skin, 240 



Bloodhound, 255 



Blubber, 18 



Blueberry, improved by breeders, 501 



Board of Health, and disease prevention, 343-344; 

 inspections, 346-347; inspector in milk plant, 347; 

 worker in laboratory, 323 



Bobcat, 17 



Body louse, 349 



Body temperature, 239 



Boll weevil, cotton. 389, 390 



Bone tissue, 130, 130 



Bones, arm, 547; ear, 281 



Boston, bird calendar, 38; water supply, 345 



Boston fern, 499, 499 



Botany, def., 3 



Boulder, def., 521 



Boy Scouts, 233 



Boyce Thompson Institute for Plant Research, 304 



Brachydactyly, def., 509 



Bracket fungus, 75 



600 



