INDEX 



llcocaecal valve, 72 



Immune reaction, 635 



Immune serum, 66 



Immunity, 65; active acquired, 65; and pro- 

 tein specificity, 635; artificial acquired, 65; 

 natural, 66; passive, 66 



Impenncs, 578, 579 



Incipient species, 653 



Incurrent canals, 276, 278 



Independent assortment, 185, 190 



Independent efiectors, cnidoblasts as, 289; in 

 coelenterates, 523; in sponsfes, 279 



Induction, 167 



Inllection point, 610 



Influenza, virus causing, 261 



Infusoriform larva, 271, 272 



Infusorigen, 270 



Ingestion, 48; in Amoeba, 233-234; in Hydra, 

 292; in invertebrates, 512; in Monosiga, 

 243; in planarians, 317; in sponges, 278 



Inheritance of Acquired Characters, Theory 

 of, 646 



Inheritance, of diseases, 199; with dominance, 

 176, 200; without dominance, 178 



Inherited behavior patterns, in birds, 579; in 

 insects, 475 



Inner ear, 91 



Inorganic evolution, 616 



Inorganic salts, 23, 29, 74 



Insecta, 216, 423, 441-478 



Insecticides, 477 



Insectivora, 579, 584 



Insects, 611; chemical coordination in, 525; 

 circulatory system of, 514; control methods 

 for, 477; fossil, 620, 621; hormonal con- 

 trol of metamorphosis in, 456; importance 

 to man, 477; in amber, 621; in pond com- 

 munity, 606; inherited reflex behavior, 475; 

 metamorphosis in, 455; nervous integration, 

 525; neurosecretory function, 526; parthe- 

 nogenesis in, 535; representative orders of, 

 457-476; reproduction in, 533; tracheal sys- 

 tem of, 517; waste storage in, 521; water 

 relations of, 602 



Instinctive behavior, in birds, 579; in in- 

 sects, 452 



Insulin, 27, 120 



Integumentary system, 57 



Intelligence, 104 



Interaction, in populations of ciliates, 613; of 

 organisms in community, 606 



Intercellular material, 34, 59, 61 



Interfertility, in domestic animals, 636 



Intermediate lobe, 118 



Intermediate mesoderm, 155 



Intermedin, 118 



Internal budding, in trematodes, 530 



Internal environment, 84, 115-126, 594 



Internal secretions, 95 



Interncuron, 98 



Interrelationships, of animal phvla, 221 



Intersex, 210 



Interstitial cells, of Hydra, 288, 292 



Interstitial fluid, 54 



Intestinal glands, 61, 72 



Intestinal juice, 72 



Intracellular digestion, in Acoela, 327; in 

 Hydra, 293; in invertebrates, 512; in pelc- 

 cypods, 373; in planarians, 317 



Invagination, 151 



Inversion, 205 



Invertebrates. 10; defined, 220 



Involuntary muscle, see Non-striated muscle 



Involution, 152 



Iodine, 118 



lodopsin, 107 



Ionic bonds, 23, 39 



Ionizing radiations, 207 



Ions, 23, 27, 29, 84, 99, 112, 113, 121, 124 



Iris, of eye, 89; responses of, 116 



Islands, continental, 632; oceanic, 632 



Islands of Langerhans, 120 



Isogametes, 136, 141; in Cnnmm, 267; in Pan- 

 donna, 267 



Isogamy, 267 



Isolation, importance in speciation, 652; 

 mechanisms of, 652; of flightless birds, 579; 

 of oceanic islands, 608, 632 



Isolecithal egg, 146 



Isopoda, 439 



Isopods, gas exchange in, 517; water relations 

 of, 602^ 



Isoptera, 458, 475 



Isorhiza, Hydra, 290 



Japanese beetle, 466, 613 



Jaundice, 84 



Java, monitor lizard of, 571 



Java ape man, 639, 640 



Jaws, Nereis, 399 



Jellvfishes, 301, 304, 305; as fossils, 621 



Jennings, H. S., 200 



Jerusalem cricket, 482 



Jingles, 380 



Johannsen, Wilhelm, 174, 201 



Joint-footed animals, see Arthropoda 



Joints, 95; ball-and-socket, 95; hinge, 95 



Jungle fowl, 636 



Jurassic Period, birds of, 574 



Juvenile hormone, of insects, 456, 527 



Kangaroo, 579, 585 



Katydid, 461, 462 



Keratosa, 274, 528 



herona, 291 



Kev industrv of communities, 608 



Kidney, 57, 82; pelvis of, 58 



Kinetochore, 41. 136 



Kinetosome, 250 



King, H. D., 200 



693 



