INDEX 



617 



Arachnida, 302-309, 311 



(iSee also Spiders) 

 Arbacia, 207 



Arboreal life, 389, 437, 450, 453 

 Arch, foot, 451 

 Archaeopteryx, 409, 410, 543 

 Archaeopteryx macrura, 410 

 Archaeopteryx siemensi, 409 

 Archaeornithes, 409 

 Archean period, 540 

 Archenteron, 121, 122, 378, 446, 466 

 Archiannelida, 247 

 Archidiskodon, maibeni, 543 

 Arctic tern, 417 

 Argonauta argo, 228 

 Aristotle, 26, 364, 544, 570, 578 

 Aristotle's lantern, 207, 208, 466 

 Armadillos, 424, 437, 534 



nine-banded, 436, 568 

 Arms, 322, 452 

 Army worm, 290 

 Arrow worm, 188 

 Arteries, 330, 580, 581 



Arthropoda, 265, 273, 276, 302, 310-311, 575, 576 

 Arthropods, 255-311, 465-467, 469, 490, 500, 541 



diagrammatic structure, 310 

 Articular cartilage, 106 

 Artificial classification, 58 

 Artificial immunity, 519 

 Artificial parthenogenesis, 114-115 

 Artiodactyla, 439 



foot bones, 435 

 Ascaris, 178-179, 491 

 Ascaris, 115, 116, 475, 526 

 Ascaris lumhricoides, 178, 178 

 Ascidian anatomy, 317 

 Ascidians, 316-317 

 Ascon, 131, 132 

 Asexual cycle, 89 

 Asexual reproduction, 46, 107, 136, 137, 142. 



151-153, 171, 253, 264 

 Asexual spore, 89 

 Asexual zooid, 253, 264 

 Asphalt lake, fossils, 538 

 Asses, 447 



wild. 535 

 Assimilation, 33, 34, 36, 43 

 Association fibers, 244 

 Associations of animals, 521-526 

 Associative memory, 505 

 Astacus, 258 



Astacus fluviatilis, section, 268 

 Asterias feeding on clam, 199 

 Asterias vulgaris, 194, 196 



bipinnaria larva, 200 

 Asteroidea, 204, 205 

 Asters, 47, 48, 114, 116 

 Astral rays, 47 

 Asymmetry, 52, 70 

 Atoll, 154 

 Atom, 8 



Atrial cavity, 317, 319, 320 

 Atrial funnel, 316, 317 

 Atriopore, 317, 319, 320 



Atrium, 320 



genital, 162-164 

 of heart, 346 



(iSce also Auricle) 

 Auditory meatus, 336 

 Auditory nerve, 336 

 Auditory organ, 277 



(See also Ear) 

 Augustine, 544 

 Aurelia, life history, 161 

 Auricle, 214, 346. 346, 367, 386, 388, 406 

 Auricularia, 210 

 Austral region, 535 

 Austrahan lady beetle, 294 

 Australian region, 633, 534 

 Author's names, 60, 573 

 Autonomic centers, 496 

 Autonomic nervous system, 333 

 Autosomes, 566 



Autotomy, 187, 201, 264, 286, 517 

 Aves, 340, 403, 409 

 Avicularia, 191, 191 

 Avoiding reaction, 72 

 Axial gradient, 165, 242 

 Axial skeleton, 324 

 Axis cylinder fiber, 243 

 Axis cylinder process, 103 



(See also Axon) 

 Axolotl, 371, 380 

 Axon, 102, 103, 243 



B 



Babbling thrushes, 535 

 Baboons, 439 

 Back swimmers, 289 

 Bacteria, 28, 86, 486, 540, 581 



in chemical cycles, 487 



in food cycle, 486 

 Bacterial action, 486, 487 

 Bacterial theory, 27 

 Bacteriology, 86 

 Badgers, 436, 445, 535 

 Bailer, 255 

 Baker, F. C,, 223 

 Balance, animal life, 508 



in body, 461 



income and outgo, 458 

 Balancers, 280 

 Balanoglossida, 315, 316 

 Balanoglossus, 315, 676 

 Balantidial dysentery, 88 

 Balantidium, 88, 315 

 Balantidium coli, 84 

 Balanus hameri, 269 

 Balanus tintinnabulum, 269 

 Baleen, 443 



Ballooning spiders, 305 

 Bandworms, 186, 187 

 Barbels, 336 

 Barbs, 404 

 Barbules, 404 

 Barn owl, 416 



Barnacles, 268, 269, 522, 626 

 Barriers to dispersal, 528, 529 



