INDEX 



707 



Hylobates, 489 



Hymenoptera, 229, 242, 250, 256, 



260, 261, 265 

 Ilynobiidae, 397 

 Ilyoid, 334, 345 



bone, 500 



plate, 345 

 Hyperbranchial groove, 318, 319 

 Hypermastigina, 49 

 Hyperparasitism, 257 

 Hyperthyroidism, 552 

 Hypertonic, 24 

 llypnotoxin, 111 

 Hypobranchial groove, 318, 319 

 Hypoglossal nerve, 353, 546 

 Hypopharynx, 250,232,247 

 Hypophysis, 350, 546, 552, 553 

 Hypostome, 103, 106, 111 

 Hypothetical ancestor, 282 

 Hypotonic, 24 

 Hypotrematica, 376 

 Hypotricha, 64 

 Hyracoidea, 464, 496 

 Hyrax, 464, 496 



Ibises, 461 

 Ichneumon, 265 

 Ichneumonidae, 265 

 Ichthyology, 10 

 Ichthyomyzon, 366 

 Ichthyophis, 404 

 Ichthyornis, 458 

 Ichthyornithiformes, 458 

 Ichthyosaurs, 427 

 Icosteida, 395 

 Icteridae, 462 

 Identical twins, 596, 597 

 Iguana, 414 

 Iguanidae, 407, 430 

 Ileocecal valve, 517 

 Ileum, 235, 236, 331 

 Iliac, artery, 532 



vein, 532 

 lliofibularis, 350 

 Ilium, 343, 345, 347, 437, 



503 

 Immunity, 527 

 Inbreeding, 593 

 Incisor teeth, 475 

 Incubation, bird's egg, 442 

 Incurrent, canal, 96 



pore, 95 



siphon, 283 

 Incus, 500, 549 

 Independent assortment, 581 



traits, 582 

 Indian, elephant, 484 



gavial, 430 



python, 420 

 Inferior nasal conchae, 500 



turbinate, 500 



vena cava, 532, 533 



Infraorbitals, 468 



Infundibulum, 350, 351, 363, 546, 

 553 



Ingestion, 112 

 Inhalent opening, 95 

 Inheritance, 572-600 



{see Heredity) 

 Injurious insects, 257-260 

 Ink sac, 294, 295 

 Innominate, 337, 338, 501 

 Inorganic salts, 518 

 Inorganic-organic cycle, 633 

 Insect, 198, 228-266, 647 



adaptive modifications, 243- 

 250 



antennae, 248 



beneficial, 254-255 



classification, 260 



coloration, 249 



digestive tract, 248 



disease vectors, 260 



eye, 231,233 



household pests, 260, 261 



injurious, to domestic animals, 

 259 

 to human beings, 260, 262 

 to plants, 257,258 



legs, 244 



life cycle, 239-242, 241, 242, 

 244, 257 



metamorphosis, 239-242 



methods of feeding, 246 



mouth parts, 246, 247 



muscular system, 255 



number of species, 230 



predaceous, 256, 257 



relations to man, 254-260 



representatives, 229 



reproductive system, 239 



respiratory system, 249 



social, 250-254 



wings, 234 

 Insect-eating bird, 446 



mammals, 482 

 Insectivora, 464, 482, 495 

 Insectivores, 495, 611 

 Insertions, muscle, 346, 505 

 Inspiration, 535, 536 

 Instinct, 556 

 Insulin, 554 

 Intelligence, 557 



Interactions between species, 636 

 Interambulacral plates, 309 

 Interatrial septum, 336 

 Interciliary fibril, 56 

 Intercostalis muscle, 467 

 Interlamellar partition, 287 

 Intermediate, horse, 618, 619, 620 



host, 640 



lobe, 398 

 Intermedin, 398 

 Internal, carotid artery, 338 



ear, 549 



gills, 358 



Internal [Cont.) : 



jugulars, 337 



oblique muscle, 467 



respiration, 333 



secretions, 540, 551 



skeletons, 500 

 Interphase, 25, 26, 28 

 Interrelations of animals, 603 

 Intcrspinous bone, 381 

 Interstitial cell, 105, 106, 107 



undifferentiated, 107 

 Intervertebral disks, 465 

 Intestinal, flagellates, 639 



gland, 518 



juice, 517 



mucosa, 554 



veins, 338 

 Intestine, 139, 140, 150, 151,152, 

 154, 164, 172, 202, 208, 

 331, 342, 517, 532 

 Intracellular digestion, 1 1 3 

 Invertase, 520 

 Invertebrate, age of, 617 



origins, 603 



relation to vertebrates, 604 

 Involuntary muscle, 86, 346, 504 

 Iodine, 519 

 Iris, eye, 550 

 Iron, 519 

 Irritabilitv, 5, 20 

 Ischium, '343, 345, 437, 438, 503 

 Islets of Langerhans, 553 

 Isolation, ecological, 622 



evolution, 61 5, 622 



geographical, 623 



seasonal, 623 



sexual, 623 

 Isopoda, 199 

 Isoptera, 229, 260, 263 

 Isospondylida, 379, 395 

 Isospora, 53, 73 

 Isotonic, 24 

 Itch mite, 275 

 Ixodidae, 279 



J 



Jacamars, 462 

 Jacanas, 452, 461 

 Jack rabbit, 496 

 Japanese spider crab, 218 

 Java ape man, 624, 625 

 Jaw, leech, 192 



Peripatus, 224 



sand worm, 184 

 Jawlcss vertebrate, 317, 360-367 

 Jays, 462 

 Jejunum, 516 

 Jellyfish, 117, 125 

 John dories, 595 

 Joint, 503 



cavity, 503 

 Jugular vein, 338, 532 

 Julus, 227 



