INDEX 



Aardvark, 630, 62,2, 638-639 



Abalone, 471 



Abdomen, of arthropods, 488 



of Cambarus, 492 



of spider, 511 

 Abdominal cavity, 129 

 Abomasum, 132, 133 

 Aboral end, of Hydra, 387 



of ctenophore, 399, 542, 545 



of echinoderm, 542, 545 

 Abyssal-benthic zone, 664, 666-667 

 Acanthocephala, 347, 443-445 

 Acanthocephalus, 444 

 Acarina, 514, 515, 516 

 Accelerator nerve, 206, 207 

 Accommodation of eye, 217, 219 

 Acellular animals, 349 

 Acetabulum, of frog, 58 



of mammal, 110 

 Acetylcholine, 207, 232 



esterase, 207 

 Achirus, 590 

 Aciculus, 451 

 Acid, 29, 30 



amino, 32, 138. 228 



carbonic, 160, 186 



fatty, 138 



hydrochloric, 138 



lactic, 121, 126, 153 



phosphoric, 120 



uric, 186 

 Acid-base balance, 160 

 Acidosis, 238 



Acipenser, 569, 582, 590, 598 

 Acipenseroidei, 590 

 Acoela, 409, 645 

 Acoelomate, 346, 347, 402, 422 

 Acontium, 396 

 Acorn barnacle {see Balanus), 489, 



507 

 Acorn worm {see Enteropneusta), 348, 



556-558 

 Acquired characters, Z22, 326 

 Acris, 596, 599 

 Acromegaly, 244 

 Acropora, 397 

 ACTH. 245 

 Actin. 121 



Actinopterygii, 568. 569, 582, 590 

 Actinosphaerium, 361 



Actomyosin, 121 



Addison's disease, 236 



Adductor, 472 



Adenosine diphosphate (ADP), 120 



Adenosine triphosphate (ATP), 120 



Adhesive gland, 564 



Adrenal artery, 167, 168 



cortex, 235-237, 668 



gland, of frog, 72, li 

 of mammal, 18, 233-237 



medulla, 207, 234 



vein, 169 

 Adrenalin, 234 

 Adrenaline, 234 

 Adrenocorticotropic factor (ACTH), 



245 

 Adult insect, 520 

 Aeolosoma, 449, 461 

 Aepyornithiformcs, 625 

 Aerobic reaction, 121, 122 

 Aestivation, 649 

 Afferent blood vessel, 188 



nerve, 203 



neuron, 195, 196, 209 

 African eyeworm {see Loa), 437 

 Afterbirth, 292 

 Agglutination, 180-181 

 Agglutinin, 180. 181 

 Agglutinogen, 180, 181 

 Agkistrodon, 609 

 Agnatha, 567, 570-575 



characteristics, 570 



divisions of class, 570-571 

 Air, bladder, 582, 586 



complemental, 156 



composition, 153, 155 



passage, 149 



pressure, 155, 221 



residual. 156 



sac, 152, 153 



supplemental, 156 



tidal, 156 

 Albatross, 625 

 Albino, 75, 312, 318 

 Alder fly, 539 

 Allantois, 291 

 Allele. 302 



multiple, 307 

 Allelomorph. 300, 302 

 Alligator. 46, 149, 567, 603, 610, 611, 

 613 



691 



