INDEX. 527 
Cetiosauria, 47, 48, 55 Crawfishes of the State of Pennsylvania, Arnold 
Cetiosaurus, 52, 53 E. Ortmann, 343 
leedsi, 254 Popular knowledge of, 492-493 
longus, 52 river species, 410 
Chelone, 289, 294 species, varieties, and variations among 
Cheloniid, 280, 296 the Pennsylvanian, 498—504 
Chelonoidea, 296 the use of, as food and bait, 493-494 
Chelydra, 290, 294 Crocodilia, 47 
Chondrosteosaurus, 50 Cruikshank, Dr. O. T., 450 
gigas, 50 Cryptobranchus allegheniensis, 495 
Cimoliosaurus laramiensis, 79 Cryptoclidus, 260 
Cockerell, Professor T. D. A., 407 oxoniensis, 259 
Coggeshall, A. S., 78, 140, 226 Cryptodira, 295 
Coggeshall, L. S., 3 Cuvier, R., 82 
Colodon, 211 Cylindrodon, 211 
Colpochelys, 290, 293, 295 Cynomys, 151-154, 156-170, 178, 181 
kempi, 294 ludovicianus, 139 
Como Beds, 67 
Comptonectes bellistriata, 79 Deemonelix, 139, 177, 185-190, 202 
extenuata, 79 Davison, Professor A. E., 425 
Conotton Creek, Ohio, 367 Dentalium subquadratus, 79 
Cook, Harold J., Jr., 316 Dermochelydide, 296 
Cope, E. D., 59, 66, 68, 82, 86, 127, 175, 174, Dermochelys, 286, 288, 290, 293 
185, 213, 305, 310 coriacea, 304 
Cosoryx, 174 Derry, Pennsylvania, 380 
teres, 174 Description of New Rodents and Discussion ot 
Coturnix noyee-zelandiz, 133 the Origin of Demonelix, 139-191 
Crawfishes as obnoxious creatures, 496, 497 Desmatochelydinz, 296 
as scavengers, 494—496 De Vries, Hugo, 503 
Bearing of the study of, on the theory of Mutation theory of, 498 
evolution, 497 Dianthera americana, 412 
Bibliography of, 513-517 Dicotyles tajacu, 309, 311 
Collectors of, 347, 348 Didelphys, 213 
Ecology and Geographical Distribution Dinosauria, 5, 20, 44, 45, 46, 47, 74 
of Pennsylvanian species of, 410—469 Diplodocide, 49 
Economic value of, 492-497 Diplodocus, 5, 6, 9, 14, 17, 23, 25, 27, 34, 35, 
enemies of, 494 39, 45, 46, 49, 55, 57, 59, 73, 75, 226, 
food of, 494 227, 233, 235, 236, 239, 245, 246, 
formation of species by isolation, 504 249, 264 
life history of the Pennsylvanian species carnegiei, 7, 11, 15, 18, 40, 74, 75, 228, 
of, 469-492 250 
morphology and chorology of the Penn- longus, 75, 251 
sylvanian species of, 350-410 vases, 264 
mountain stream species, 413 Diprodontia, 48 
historical review of our systematic knowl- Dogtown Mine, Montana, 212 
edge of, 348-350 Dolichorhynchops osborni, 85 
