INDEX. 



Acanthocephala, 109 ; general characters of, 



Acanthometra, 38, 39. 

 Acanthophis, 245. 

 Acanthopteri, 219. 

 Acarina, 141. 

 Achetina, 155. 

 Acorn-shells, 136, 13,. 

 Acrydium, 156. 

 Actinia, 51, SB. 



, 52, 53 ; general Characters of, 84 ; 

 orders of, 86-94. 

 Adjutant, 269. 

 Agouti, 311. 

 AUurus, 308. 



Air-receptacles of Birds. 261. 

 Alcedinidce, 277. 

 Alces, 301. 

 Alcidae, 267. 



Alcyonaria, 86; characters of, 90. 

 Alcyonium, 90. 



ul^CB, 4. 



Alligator, 248. 



Alpaca, 301. 



Amblystoma, 228. 



Ainbulacral system of Echinus. 18, 99. 



Ameiva, 245. 



Ametabolic Insects, 150, 153. 



Ammonites, 195. 



Amo&ba, 30 ; nucleus of, 32 ; reproduction of, 



Amo&bea, 30. 



Amphibia, 195, 205; general characters of, 



225; orders of, 226-233. 

 Amphioxus, 214, 215. 

 Amphipoda, 138. 

 Anacanthini, 219. 

 Analogy, 15. 

 Anarthropoda, 119. 

 Anatidce, 267. 

 Anguillula, 115. 

 ^wgrww, 245, 246. 



Animals and plants, differences between, 3-6. 

 Annelida, 119; general characters of, 120; 



typical segment of, 120; divisions of; 



Annuloida, 15 ; characters and divisions of, 



95. 



Annulosa, 15; general characters of, 118. 

 Anomodontia, 237, 252. 

 Anomura, 131. 



Anoplura, 153. 



Anoura, 226, 230, 232. 



Anserince, 267. 



Ant-eaters, 282, 286. 



Antelopes, 803. 



Antenna;, 124, 139, 149. 



Anthropoid Apes, 317. 



Ant-lion, 156. 



Ants, 161, 162. 



Apes, 315, 81T. 



Aphaniptera, 158. 



Aphides, 154, 155. 



Aphis-lion, 156, 157. 



Aphrodite, 124, 125. 



Apidce, 160. 



Aplacental Mammals, 286, 287. 



Aptera, 150. 



Apteryx, 270, 271. 



Apus, 138. 



Aquiferous system (Sponges), 41. 



Arachnaetis, 86. 



Arachnida, 127; general characters of 139; 

 orders of, 140-144. 



Araneida, 142. 



Archceopteryx, 279. 



Arctomys, 312. 



Ardea, 269. 



Ardeidw, 269. 



Arenicola, 124, 125. 



Argonauta, 190, 191. 



Armadillos, 286. 



Arms, of Srachiopoda, 175; of Cephalo- 

 poda, 188, 190, 191. 



Arthropoda, 119; general characters of, 126. 



Articulata, 126. 



Artiodactyla, 297, 298. 



Ascaris, 115. 



Ascidian Mollusks, 171 ; solitary, social, and 

 compound, 173. 



Asinus, 298. 



Ass, 298. 



Asteroidea, 96; general characters of, 100, 

 101. 



Atolls, 89. 90. 



Atrium (Tunicata), 173. 



Auchema. 301. 



Aurelia, 80. 



Aves, 205 ; general characters of, 253 ; feath- 

 ers of, 253; vertebral column of, 254; beak 

 of, 255; pectoral arch of, 255; hind-limb of, 

 257; foot of, 258; digestive system of, 258; 

 respiratory system of, 260; circulatory 



