446 



INDEX 



Appendix, human, 88, 398 



Apterygota, 13G 



Aquinas, Thomas, 8 



Arachnida, 135 



Arboreal origin of man, 191 



Arboreal quadrupeds, 191 



Archaeopteryx lithographica, 155, 156 



Archenteron, 42 



Archeozoic, 124; fossils of, 129 



Arches, branchial, see Branchial 

 arches 



"Arcturus Adventure," 260 



Argonaut a, 132 



Aridity, adaptations to, in animals, 

 224; in plants, 224 



Arisaema triphyllum, sex reversal in, 

 336; Siamese twins, 337 



Aristotle, 5, 7 



Armadillo, 236 



Armor, of alligator, 236; of arma- 

 dillo, 236; of Stegosaurus, 235; 

 of Triceratope, 235, 236 



Arthropod theory of vertebrate ori- 

 gin, 144 



Arthropoda, 28; adaptations of legs, 

 218; ancestors, 134; aquatic, 135; 

 burrowing, 221; terrestrial, 136 



Artiodactyla, 164 



Ascaris, germinal continuity, 306, 422 



Asexual propagation, 350 



Asphalt, 124 



Asses, 164, 183, 345 



Associations, animal, gregariousness, 

 237; communal, 239; commensal, 

 240; symbiosis, 240; parasitism, 

 240 



Asterias fo7-hesii, 265 



Auchenia, skull, feet, and teeth, 1S5 



Augustine, 8 



Australian region, 255, 256 



Auslralopitliecas africanus, 201 



Autosomes, 299 



Autotomy, 237 



Aves, see Birds 



Axolotl, 95, 211 



Babcock and Clausen, 275, 317, 342, 



345, 347, 350 

 Back-cross, 285 

 Bacon, 8 

 Baplanodon, 153 

 Barnacles, 214 

 Barriers, 257 



Basques, 207 



Bateson, 264, 269, 319 



Bats, 227, 253 



Beagle, voyage of, 14 



Beaks, of carnivorous birds, 233, 235; 

 of seed-eating birds, 234, 235; of 

 insectivorous birds, 234, 235 



Bear animalcules, 137 



Bears, polar, 260 



Bechuanaland, 199 



Beebe, Wm., 2, 14, 216, 244, 254, 260, 

 394, 409 



Bee moth, 347 



Bees, evolution in, 397; and fruit, 231 



Beetle, Japanese, 251 



Beetles, jumping adaptations, 220; 

 running leg of tiger beetle, 21S; 

 swimming leg of gyrinid, 218; 

 Schroder's experiments with, 420 



Belemnites, 133 



Belostomatidae, 254 



Benedict, a Clydesdale stallion, 352 



Benthos, 214; aerial, 217 



Beresovka mammoth, 126 



Bering isthmus, 258, 259 



Biology, 11 



Biometry, 15, 275 



Bipedality, 219 



Birds, 37; adaptations for securing 

 food, 233, 235; digestion, 227; 

 feathers, 225; flight adaptations, 

 225; metabolism, 228; origin of, 

 154; respiration, 228; secondary 

 sexual characters, 334; sex reversal 

 in, 327; skeleton, 225; tail and wing 

 functions, 225; temperature, 228; 

 and warning colors, 242; mocking, 

 409 



Birth rate, 377; decrease in, 377; of 

 the unfit, 378; of mentally normal, 

 378; and immigration, 380 



Bison, 347 



Blastocoele, ^0 



Blastula, jO, 41 



Blending inheritance, 318 



Blood, 113 



Blood tests, 95 



Blue Andalusian fowl, 281 



Body cavity, 35 



Boveri, 301 



Brachiation, 193 



Brachiopoda, 28, 132 



Brachiosaurus, 153 



