Index 



Acquired characters, lO 

 Adaptations, 248 

 Advanced fish, 48, 51 

 Air-bladder, accommodation to 

 salt and fresh water, 134 



adjustment of, 127 



connection with ear, 129-132 



connection with throat, illus- 

 trated, 136 



as depth indicator, 128, 129, 

 136 



description of, 124 



evolution of, 123 



as float, 134 



as hearing auxiliary, 130-132 



as hydrostatic organ, 124-126, 



i33> 13s 



oxygen in, 133 



respiratory function, 132 



as sound-producer, 135 

 Age, 173 



Alaska blackfish, 21 

 AnablepSy 82 

 Angler-fish, 258 



illustrated, 258, 269 



parasitic male, 269 

 Artificial propagation, 165 



of black bass, 167-168 



of salmon, 165-166 



of trout, 166-167 

 Atlantic Ocean, 165 



Barbels, 115 



Bass, black. See Black bass 



striped. See Striped bass 

 Bermuda, 44, 100 

 Betta, 160-161, 250 



illustrated, 251 

 Biogenetic law, 45, 63, 82 

 Biological requirements, 230-231 

 Biology, fisheries, 224 

 Black bass, 214, 245 



artificial propagation, 1 67-168 



caecay 143 



color discrimination, 97 



growth, 218 



habitat, 214, 215, 216 



hatching period, 168, 218 



illustrated, 6 



memory, 98 



pre-hatching mortality, 219 



spavining, 167, 217, 218 



species distinction, 215 



transplantation, 214, 215 



versus trout, 215 

 Blackfish, Alaska, 21 

 Blood, circulation, 153 



function, 153 

 Blow-fish, 223 

 Bluegill sunfish, 246 

 "Blue-head," 44 

 Bonneville Dam, 230-234 

 Brain, 116 



illustrated, 117 



277 



