INDEX. 



Aard vark, 636 

 Abalone, 379 

 Abdominal cavity, 546 

 Abdominales, 562 

 Abdominal fin, 562 

 Abdominalia, 426 

 Abducens nerve, 536 

 Abomasum, 642 

 Acantharia, 196 

 Acanthia, 489 

 Acanthias, 569, 571 

 Acanthiidae. 489 

 Acanthin, 195 

 Acanthobdella, 318 

 Acanthoderus, 48 

 Acanthobothrium, 286 

 Acanthocephala, 304 

 Acanthocotyle, 274 

 Acanthodes, 572 

 Acanthodidoe, 572 

 Acanthoglossus, 632 

 Acanthometra, 194 

 Acanthophracta, 196 

 Acanthopteri, 57^, 577 

 Acanthopterygii, 577 

 Acaridse, 454 

 Acarina, 453 

 Accessory nerve, 536 

 Accessory tissue, 99 

 Accessory yolk, 80 

 Accipiter, 617 

 Acephala, 358 

 Acerata, 442 

 Acetabula, 280 

 Achseta, 317 

 Achatina, 383 

 Achoreutes, 477 

 Achromatin, 65 

 Achtheres, 36, 422 



Aciculum, 308 

 Acineta, 212 

 Acinetaria, 212 

 Acinous glands, 77 

 Acipenser, 573 

 Acipenseridae, 573 

 Acmaea, 378 

 Acmaeidae, 378 

 Accela, 271 

 Acontia, 253 

 Acorn barnacle, 423 

 Acrania, 502 

 Acraspedia, 246 

 Acraspedota, 246 

 Acridiidae, 481 

 Acridium, 481 

 Acris, 588 

 Acrodont teeth, 599 

 Actinaria, 259 

 Actinian, section of, 136 

 Actinophrys, 191, 192 

 Actinopoda, 349 

 Actinosphaerium, 190, 192 

 Actinotrichia, 527 

 Actinotrocha, 325 

 Actinozoa, 251 

 Aculeata, 486 , 



Aculeus, 472, 476 

 Acustic nerve, 536 

 Adambulacral plate, 335 

 Adamsia, 254 

 Adhesive cells, 264 

 Adipose fin, 576 

 Adoral band, 209 

 Adradius, 246 

 &ga, 441, 442 

 ^gina, 242 

 JEotidx, 382 

 ^olidia, 382 



657 



