INDEX 



[The names of the genera cited are printed in italics. The numerals refer 

 to pages. Those in bold-faced type indicate that the object is illustrated on 

 that page.] 



Absorption, 66 



Abyssal fauna, 135 



Acalephs, 245 



Acanthocephala, 203 



Acanthopteri, 372 



Acclimatization, 13, 105 



Achromatin, 21, 27 



Acquired characters, 100, 102 



Actinozoa, 180 



Adaptation, means of, 105; types of, 

 in; to inorganic environment, 112; 

 to mates, 114; to offspring, 115; 

 social, 120; competitive, 121; com- 

 mensal, 122; symbiotic, 122; to prey- 

 ing, 125; for protection, 125 



Adaptive habits and instincts, 132 



Adipose tissue, 55 



Adrenals, 341 



Aepyornis, 412 



Aerial fauna, 136 



Age of man, 472 



Air-sacs (birds), 404 



Aix, 412 



Albatross, 414 



Alimentary canal (see digestive sys- 

 tem). 



Allantois, 391, 408 



Alligator, 396 



Allolobophora, 222 



Alternation of generation in Coelen- 

 terates, 178; in worms, 191, 196 



Ambulacral system, 213 



Amitotic cell division, 24 



Ammonites, 262 



Amnion, 391, 408 



Amceba, 15, 23, 92, 149 



Amphibians, 144, 375 



Amphioxus, 312, 313 



Amphitrite, 236 



Amphiuma, 380 



Ampullae, 214 



Anabolism, 66 



Anacanthini, 373 



Analogy, 84 



Anaphase, 25 



Anatomy, 3, 511 



Animalcules (see protozoa). 



Animal industries, 505 



Annelids (see annulata). 



Annulata, 146, 222, 236 



Anodonta, 238, 258 



Anseres, 415 



Ant-eater, 451 



Antenna, 267 



Antennule, 269 



Antero-posterior (see symmetry) . 



Antimeres, 96 



Ants, 121, 306 



Anura, 313 



Aorta, 338 (see circulatory system). 



Apes, 459 



Aphis (plant lice), 299 



Appendages arrangement of, 96; in 



arthropods, 278; in vertebrates, 324; 



in fishes, 359; in amphibians, 376; 



in birds, 401 



Appendicular skeleton, 330, 332 

 Appendix, 445 

 Applications of zoology, 510 

 Aptera, 297 

 Apteryx, 406, 410 

 Aquatic fauna, 135 

 Arachnida, 306 

 Araneida, 307 

 Arbacia, 209 

 Archceopteryx, 409 



533 



