414 



PRINCIPLES OF ANIMAL BIOLOGY 



Crayfish. 273 



nervous system of, 141, 142 

 Cretaceous, 330, 335 

 Cretinism, 154 

 Crinoidea, 269 

 Cro-Magnon man, 345, 346, 367 



cave engraving by, 347 



tools used by, 347 

 Crop, of earthworm, 101, 102 

 Cross-fertilization, 180, 181 

 Crustacea, 273, 274 

 Crystalline lens, in embryo, 211, 213 

 Ctenophora, 275 

 Cubical epithelium, 84 

 Cuvier, Georges, 14 



taxonomy by, 246 

 Cyclostomata, 276, 278 

 Cytology, 19, 20 

 Cytosome, 23, 27 



division of, 61 



D 



Dark Ages, 6-7 

 Darwin, Charles, 17, 18 



natural-selection theory of, 360, 361, 

 364 

 Deficiency diseases, 110 

 Democritus, 3, 4, 5 

 Demospongiae, 262 

 Dendrite, 143, 144 

 Dendritic colony, 67, 68 

 Dermatozoa, 247 



Desiccation, resistance to, 285, 286 

 Determinate development, 218 

 Determination, principle of, 217-220 

 Development, place of, 182, 183 

 Devonian, 330, 335 



De Vries, Hugo, study of mutation by, 353 

 Diaphragm, 117 

 Differentiation, leading to metazoa, 



69-72 

 Diffusion, 43 

 Digestion, 48 



human, 104-106 



locus of, 100, 101 

 Digestive systems, 101, 102, 103 

 Dinosaurs, 332, 334, 335 

 Dinotherium, 337, 339 

 Dioecious, 166 

 Dioecism and fertilization, 181-182 



Diogenes of Apollonia, 2 



Diploblastic, 262 



Disaccharide, 40 



Distribution, as evidence of evolution, 



352 

 Division, taxonomic, 248 

 Domestic animals, evolution of, 366, 367 

 Dominant, 225 

 Dormancy, 281, 282 

 Dorsal aorta, 123 

 Drosophila, chromosomes in, 59 



heredity in, 230, 234, 235, 236 



mutation in, 355, 356 

 Duodenum, 102 



Dutrochet, discovery of cells by, 15 

 Dyads, 194, 195, 197 



E 



Ear, development of, 214 



in embryo, 213 

 Earthworm, body cavities in, 80 



digestive system of, 101 



metameric, 79 



nervovis system of, 141, 142 



reproduction of, 166-168 



seta in, 89 

 Echinodermata, 267-269 

 Echinoidea, 268, 269 

 Echinorhynchus, 275 

 Ecological succession, 291-293 



in peat bed, 292 

 Ecology, 21, 22, 281-306 

 Ectoderm, 204, 206, 207, 208, 209, 210, 

 211 



of Hydra, 71, 72, 73 



organs from, 207 

 Edaphosaurus, 333 

 Eel, migration of, 318 

 Effector, 145 

 Efferent neuron, 145, 146 

 Egg, 199, 200 



of Hydra, 72 



mature, 198 

 Eggs, care of, 186-189 

 Elasmobranchii, 276, 277, 279 

 Electrolysis, 37 

 Electrolytes, 36, 37 

 Electron, 31 

 Element, 30, 31-33 

 Elephant, evolution of, 335-339 



J 



