INDEX 



419 



Davidson, J., 313 



Davis, W. T., 79 



Deegener, P., 6, 7, 8, 9, 13, 14, 15, 17, 

 19, 20, 22, 23, 25, 26, 27, 28, 29, 30, 

 31, 33, 34, 36, 38, 47, 49> 61, 101, 

 340, 353 



Deer, 13 



Deere, E. O., 236, 239 



Demuth, G. S., 70 



Dendrocoelitm, mass protection from col- 

 loidal silver, 203, 210, 2ir 



Dermestes, food exhaustion, 102 



Desiccation, land isopods, protection 

 from, by crowding, 182 



Desmones, 150 



De V^arigny, H., 109, no, 112, 119 



Diphyletic tree, 356 



Diptera abundance, 359 



Ditmars, R. L., 68 



Division of labor, 337, 343, 346, 350, 362 



Dociostaurus, see Grasshoppers 



Domm, L. V., 309 



Downing, R. C., 289 



Downs, V. L., 43 



Drew, A. H., 157 



Drosophila, 20 



aggregations conditioned by moisture, 



73 

 crowding, reduces rate of reproduction, 

 116, 131, 280 

 affects growth form, 331 

 affects Mendelian ratios, 332 

 factors affecting rate of reproduction, 



. 134, 236 

 optimum population for growth, 148 

 density of population and longevity, 

 240 

 Drzewina, A., 125, 140, 142, 191, 201, 202, 

 203, 206, 207, 208, 209, 212, 217, 

 219, 222, 223, 23s, 259, 265, 274, 

 275, 276, 277, 278, 284, 285, 354 

 Ducks, flocks of, 342, 345 

 Duckweed, "auximones" and, 159 

 Dumas, J. B., 263 

 Durkheim, E., 355 



Earthworms, laboratory aggregations, 74 

 Earwigs, heteromorphic societies, 24 

 Ebeling, A. H., 106, 151, 157 

 Echinoderma, 12, 357 



growth, limited by crowding, no, 117, 

 118, 312 



promoted by crowding, 153 

 eggs, development hastened by crowd- 

 ing, 156 

 mass protection, from KCN, 215 



of sperm, 218, 263 

 see also Ophioderma and Sea urchins 

 Echinus, see Sea urchin 

 Ecological succession, in plants, 103 



in protozoan infusions, 107 

 Ecology, 4, 8, 52 



Egg production in hens, reduced by 

 crowding, 126 

 seasonal values, 129 

 Eigenbrodt, H. J., 148, 332 

 Eijkman, C., 104, 106 



Electrical resistance of hypotonic sea- 

 water, 225 



Electrolytes, crowding on resistance to, 



140 

 Elephants, mixed families, 28 



heterotypic groups, 30 

 Ellicott, E. L., 68 

 Emergence of society, 339 

 Emerson, A. E., 30, 95, 96 

 Enchelys, allelocatalysis, 161, 169, 



mass protection from high tempera- 

 tures, 217 

 Enchytraeis, 32, 51 

 Ephydra (Diptera), 358 



Espinas, A. V., vii, 6, iz, 34, 47, 352, 353, 



360 

 Essenberg, C, 52 



Ether, mass protection against, 237 

 Ethyl alcohol, mass protection against, 



237, 238 

 Ethylene chloride, mass protection against, 



237 

 Ell glen a, 171 

 Evermann, B. W., 72 



Evolution, animal, 361 

 social, 362 



Excretions retard growth of bacteria, 

 103, 107 

 of snails, no 



or echinoderm larvae, no, 117 

 of Daphnia, no 

 of Planaria, 113, 312 

 of fish, 113, 116 

 retard rate of reproduction, 120 

 of Paramecium, 120 

 ol Stylonyckia, 122 

 of Daphnia, 126, 304 



