_Alligator_, _39_, _210_, _212_; hyoid, =285=; limbs, =264=; pectoral girdle, =262=; pelvis and sacrum, =267=; scutes, 271; skull, =245=, =248=, =253= Alligatoridae, 39 _Alytes_, _36_; fronto-parietal fontanelle, 179; vertebrae, 172 Amblypoda, _47_; general characters, 363; manus, 510; pes, 525; skull, 473; teeth, 433; thigh and shin, 519 _Amblystoma_, _35_; skull, 175 American monkeys, _373_; see _Cebidae_ American vultures, _41_; vomers, 335 _Amia_, _33_; distribution, 66; exoskeleton, 67; pectoral fin, 131; scales, 105; skull, 123; tail, 115, 117; vertebrae, 114 Amiidae, _33_ _Ammocoetes_, _31_, _55_ Amphibia, _35_; anterior limb, 185; exoskeleton, 168; general characters, 133; hyoid apparatus, 180; pectoral girdle, 184; pelvic girdle, 187; posterior limb, 188; ribs, 182; skull, 173; sternum, 182; teeth, 169; vertebral column, 170 Amphicoelous, defined, 14 _Amphioxus_, _30_; skeleton, 51 f.; spinal column, 112 _Amphisbaena_, _38_, 272; loss of limbs, 289 Amphisbaenidae, _38_, _200_; pectoral girdle, 288; skull, 277; vertebral column, 275 Amphitheriidae, _43_ _Amphiuma_, _35_, _135_; manus, 187; pes, 188; skull, 174 Amphiumidae, _35_ Anacanthini, _33_ Anal shield, turtle, 215 _Anas_, _41_; _A. boschas_, see Duck Ankylosis, defined, 12 Angel fish, _32_ Angler, attachment of teeth, 107 Anguidae, _38_ _Anguilla_, _33_; see Eel _Anguis_, _38_; loss of limbs, 289; scutes, 271 Angular, 22; cod, 100; crocodile, 258; duck, 319; salmon, 94; turtle, 231 Angulo-splenial, frog, 161 Ankle joint, duck, 327; reptiles, 294 Anomodontia, _36_ Anoplotheriidae, _45_ _Anoplotherium_, _45_; manus, 506; pes, 523; tail, 454; teeth, 428 _Anser_, _41_ Anseres, _41_; aftershaft, 329; claws, 330 Anseriformes, _41_ Anteaters, _352_; absence of teeth, 424; manus, 505; pectoral girdle, 495; pelvis, 513; skull, 458; thoraco-lumbar vertebrae, 447; Spiny --, _43_; Great and Two-toed --, _44_ Antelope, _359_; manus, 507; Four-horned A., _46_ Anterior limb, 26; Amphibia, 185; birds, 338; crocodile, 263; dog, 405; duck, 322; frog, 164; newt, 147; reptiles, 290; turtle, 232 Anthropoid apes, _373_; arm-bones, 503; pelvis, 515 Anthropoidea, 49; general characters, 372; sacrum, 452; skull, 482; teeth, 441 _Anthropopithecus_, _49_; ribs, 493