INDEX 
Figures in heavy-faced type indicate illustrations. 
A 
Abdominal ribs, 79 
Adaptation ot feet, 361, 362 
Adaptative Radiation, 15-18; in war- 
blers, 361-367 
Adjutant, head of, 273, 276; hair 
from neck of, 276 
fEpyornis, com. size of egg of, 461 
Aftershatt, 36 
Aggressive coloration, use of, 30S, 
in Arctic fox, 309; in Cuckoo, 311; 
in Gyrfaleon, 309, 312; in Ivory Gull, 
309, 311; in Penguin, 309, 310; 
in pickerel, 310; in Snowy Owl, 309, 
313 
Air-saes, ef. with respiratory system 
of insects, 173: extent of, 173: 
funetion of, 174, 177; in Prairie Hen, 
Ve 
Albatross, wing of, 320, 321, 325, 332 
Albinism, 314 
Alligator, egg of, 429; foot of, 354; 
nictitating membrane of, 215; re- 
lation to birds, 9; skull of, 105 
Altricial nestling, 30 
Amoeba, 185, 186, 463 
Amphioxus, 66; gill-clefts in, 473; 
notochord of, 66; segments of, 73; 
trachea of, 169; breathing motions 
in, 180 
Anaximander, 12 
Ancestors of birds, 1-18 
Aorta, 476 
Apoplexy in birds, 202 
Apteryx, ody-feathers of, 289; eyes 
in, 254, 255, 256; sense of touch in, 
219 
Archiwopteryx, as parallel branch, 10; 
as ancestral type, 10; foot of, 353; 
general description of, 7; in Berlin 
Museum, 11; in British Museum, 8; 
probable habits of, 12-13; restora- 
tion of, r4; tail of, 398, 399, 400, gor 
Aristotle, ef. with Darwin, 12 
Artery, 182 
Arteries, course of vertebral, 79 
Atlas of Jabiru, 72 
Auk, wing of Great, 339, 340; wing of 
razor-billed, 339, 340 
Avocet, bill of, 237, 239 
Axis of Jabiru, 72 
B 
Back-bone, of Amphioxus, 66; evolu- 
tion of, 64-70; of sbark, 68 
Barbs, of Condor’s feather, 32 
Barbicels, 32, 54 
Barbules, 32, 34 
Bats, keel of, S3-S4; used as food. 158 
Beak, see Bill 
Beaks and Bills, 223-251 
Bear, feet of, 1o0z 
Bellbird, wattles of, 273 
Biil, 
function of, ; , 250, 251 
of Avocet, , 239; Archieopteryx, 
226; Cormorant, 227, 228; Cross- 
bill 24, 249, 245; Crow, 226; 
Shoveller Duck, 233, 235; Purple 
Finch, 249; Golden Eagle, 242; 
Flamingo, 128, 234, 235, 236; 
Gannet, 227, 228;  Boat-billed 
Heron, 237, 238; Great Blue Heron, 
237; Night Heron, 237; Huiahird, 
248, 249, 250; Hummingbirds, 244, 
245, 246, 247, 248; Ibis, 237, 230; 
Shell This, 240; Merganser, 233, 
234: Nuthatch, 245: Owls, 242: 
Ovster-catcher, 238, 240; Parrots, 
242; Pelican, 228, 229, 230; 
Crook-billed Plover, 240, 241; 
American Raven, 225; Black Skim- 
mer, 231, 232, 236; Snakebird, 
228, 220; Dowitcher Snipe, 241; 
Spoonbill, 220, 286, 239; Stilt, 237; 
Chimney Swift, 244, 246, 245; 
Tailor-bird, 245; Tern, 231, 232; 
Toucans, 243, 244; ‘Triceratops, 
485 
