Columella cranii, 200 n; see epipterygoid Colymbi, _40_ Colymbiformes, _40_ Compsognathidae, _38_ _Compsognathus_, _38_, 208 Condylar ridge, duck, 326 Condyle of humerus, dog, 406; of mandible, dog, 398 Condylarthra, _47_; femur, 519; general characters, 361; manus, 509; skull, 472; teeth, 432 Contour feather, duck, 303 Copula, 23 _Coracias_, _42_; see Roller Coraciae, _42_ Coraciiformes, _42_ Coracoid, 25; cod, 103; crocodile, 263; duck, 322; frog, 163; Monotremata, 493; newt, 147; reptiles, 288; turtle, 232 Coracoid groove, duck, 321 Cormorant, _41_; foot, 342; skull, 335 Cornu, see hyoid Cornua trabeculae, 18 _Coryphodon_, _47_; femur, 519; manus, 510; pes, 525; skull, 473; teeth, 433; _C. hamatus_, manus, =510= Coryphodontidae, _47_ Costal plate, turtle, 215; -- process, duck, 321; -- shield, turtle, 214 Cotyloid bone, 25, 513; see Acetabular bone Cotylopidae, _45_ _Cotylops_, _45_; pollex, 506; skull, 468 Coverts, 306, 328 Cranium, 18; cod, 96 f.; crocodile, 244 f.; development of, 16 f.; dog, 384 f.; dogfish, 73 f.; duck, 314; frog, 154 f.; newt, 140 f.; turtle, 222 f. Cranio-facial axis, dog, 384 Creodonta, _48_; carpus, 512; femur, 520; general characters, 368; skull, 479; teeth, 439 Cribriform plate, dog, 388, 400 Crocodile, _210_, _212_; anterior limb, 263; exoskeleton, 237; pectoral girdle, 262; pelvic girdle, 266; posterior limb, 268; ribs and sternum, 259; skeleton, 237 f.; skull, 243 f.; tarsus, 293; teeth, 238; vacuities in surface of cranium, 256; vertebral column, 239 Crocodilia, _39_; general characters of, 210; palate, 281; skull, 277 f.; succession of teeth, 274; teeth, 273 Crocodilidae, _39_ _Crocodilus_, _39_; _C. palustris_, sternum and associated bones, =261=; late thoracic and first sacral vertebrae, =242=; _C. vulgaris_, cervical vertebrae, =239= Crossopterygii, _33_; general characters, 68 Crotalidae, _38_ _Crotalus_, _38_; jaws 280; see Rattlesnake Crows, _42_ Crura of stapes, dog, 393 Cruro-tarsal, ankle joint, 345 Crus, 26; crocodile, 268; dog, 412; duck, 326; frog, 166; newt, 149; turtle, 235 Crusta petrosa, 5 _Cryptobranchus_, _35_, 135; skull, 175; _C. lateralis_, sacral vertebrae, 171 Cryptodira, _37_; characters, 194 Ctenoid scales, 8, 60, 105 Cubitals, 303 f. Cuboid, 27; dog, 415 Cuckoo, foot, 342 Cuculi, _42_