644 



ANIMAL BIOLOGY 



Setae, 234, 236, 260, 575 

 Sex, 45 



determination, 566, 667 

 Sex cells, 45, 86, 96, 109-113, 135, 136, 151, 253, 



470, 476. 559, 560, 567 

 Sex chromosomes, 566, 568 

 Sex hormones, 492 

 Sex-linked character, 568-569 

 Sex organs, 169, 240 

 Sexual cycle, 89 

 Sexual dimorphism, 471, 572 



Sexual reproduction, 46, 87, 107, 134, 142, 151, 

 164, 253, 317-318, 470-471 

 (See also Reproduction) 

 Sexual spores, 89 

 Sexual zooids, 253, 254 

 Shaft, 404, 406 

 Shank, 404 

 Sharks, 340, 344-349, 523, 542, 579 



brain, 346 

 Sheep, 439, 535 



liver fluke, 172-174 

 skull, 426 

 Shelford, 506 



Shell, 192, 193, 212, 213-215, 219-224, 230-232, 

 400-401, 641, 574, 575 

 glands, 168, 494 

 Shipworm, 225, 231, 233 

 Shore faunas, 611 

 Short digits, 566 

 Shrews, 434 

 Shrimps, 270, 271 

 Sight, 192, 193, 212, 213-215, 219-224, 230-232, 



400-401, 641, 574, 575 

 Silicon, 20 



Silk, 287, 303-305, 491, 499 

 Silkworms, 83. 278, 287, 491, 498-500 



cocoon, 498 

 Silurian period, 193, 229, 309, 539-541 

 Simple epithelium, 98 

 Simple reflexes. 498 

 Sinanthropus pekinensis, 452 

 Sinus venosus, 346, 346 

 Sinuses, 259, 304, 336 

 Siphons. 208, 212 214, 226, 227 

 Siphuncle. 228 

 SipuncuUd. 262 

 Sirenia. 429. 441 

 Size limit. 45 

 Skates, 340, 347, 348 

 Skeletal lamina, 86 

 Skeletal muscle, 102 

 Skeletal system, 104, 105, 465 



(See also Skeleton) 

 Skeleton, 132, 312, 313, 322, 324-326, 335, 350, 

 351, 356, 424-425, 450-451 

 bird, 404 

 fish, 365, 367 

 man, 326 

 snake, 393, 398 

 turtle, 400 

 Skin, 105, 324. 345, 365-366, 373, 464-465, 467, 

 491 

 frog, 366 



Skin, gills, 468 



(See also Dermobranchiae) 

 insect. 466 

 Skull, 324, 326, 342, 356, 424-425, 546 

 snake, 390 

 types. 426 

 Skunks. 436. 445 

 Sleeping sickness, 88 

 Sloths, 437, 438, 534 

 Slugs, 224 



Small intestine, 327, 328, 329 

 Smallpox, 519 

 Smell, 334-336, 359, 473 



(See also Olfactory organs) 

 Snails, 10, 221, 223-225, 230, 509 

 Snakes, 340, 386, 389, 393-398, 445, 532 

 boa, 393 

 copperhead, 397 

 coral, 397 

 eggs. 394 

 garter, 392 

 head. 390 

 rattle. 396 

 skeleton. 393 

 skull. 398 



water moccasin, 396 

 Snapping turtles, 401 

 Sneezing, 496 

 Snipe, 412, 413, 414 

 Snout, 424 

 Soaring, 411 

 Social insects, 296 

 Societies, 296-300, 521, 522 

 Sociology, 5 

 Sodium, 19 



Sodium carbonate, 330, 491 

 Soft-shelled crab, 263 

 Sol, 13, 14 

 Soldier ant, 299 

 Soldier termite, 288 

 Sohd, 9 



Solitary bees, 298 

 Solitary life, 521 

 Solute, 11 

 Solutions, 11 

 Solvent, 11 

 Soma, 479 



Somatic cells, 95, 96, 479 

 Somatic mesoderm, 125, 313, 383 

 Somatoplasm, 96, 479, 545 

 Somatopleure, 383, 384 

 Song birds, 414, 416, 417 

 Songs, bird, 417 

 Sounds, insects, 277 

 Sow bugs, 266 

 Special creation, 26, 580 

 Specialization, 204, 247, 300, 310, 467 



(See also Adaptation) 

 Species, 3, 59, 550, 571 



origin of, 545 

 Sperm, 45, 109 



whale, 4, 441, 448 

 Sperm cells, 31, 45, 107-117, 134, 142, 152, 163, 

 164, 181, 218, 240, 241, 251, 300, 310, 340, 

 361, 377, 445, 476, 521, 556, 668, 560. 583 



